general-tech

[eternal crow]

Hello all... was wondering if someone could point me in the direction for a project. Short version is, its for a gps wearable project, but I would like to control how often the gps reports its location. Reason I want to control that is, the wearable isn't for a person, for cattle. So if I can control that piece I can extend battery life. Changing batteries with cattle isn't the most convenient thing to very often. Or if solar is an option and small enough I'll consider that also.
Thanks

[tall gyro]

Without knowing more I would suggest starting here -> https://github.com/Open-Source-Range/OSR_GPS_Collar

[delicate quarry]

Do you have a GPS module or chip already selected? If not, https://www.adafruit.com/product/4415 has various low-power modes available depending on your needs.

Wearable solar is slowly becoming a thing, but there aren't a whole lot of products yet available for it. If you know your way around charging circuits, you might be able to snag some small flexible panels from AliExpress or Amazon, but I don't know of a prebuilt module to really make use of them myself.

[pearl frost]

I've seen little solar panels that are ~1cm square
would be kind of cool if you could weave them together but I imagine you'd end up with hotspot problems

and expensive+ delicate

[delicate quarry]

https://www.amazon.com/jiang-Flexible-Photovoltaic-Waterproof-thickness/dp/B07D7PS8MW/ is a thing, and you might be able to get some juice out of it with a TPS4056 module?

It ain't cheap, though, and I don't know how many of these you're going to need...

[eternal crow]

I don't have anything picked out yet, just checking to see what is out there and if its affordable for me. As for the number maybe at the most 75. I wasn't sure if I could find a doable solution where I could get batteries to last..5 months. I know that is a long time and might not even be possible thats why I was asking. For the most part the only time we have cows up and accessible is spring and fall. If could make it, from around this time to early September. And gps doesn't have to ping every 10 seconds...heck every 20 or 30 minutes would work.

[delicate quarry]

The GPS is pretty easy, and the battery isn't completely out of the question. The harder part of this would probably be how you plan to communicate with 75 different collars individually. If you simply want to transmit your GPS data once every 20-30 minutes unidirectionally, this might not be too bad, but the complexity jumps up the moment you want to be able to locate any particular cow...

Your first step would be to gather the necessary hardware and test how much current your proposed hardware would draw during transmission, and how much it would draw between transmissions. Given the various combinations of different hardware and configuration options, this will be a fair number of data points, but this will allow you to gauge how large of a battery you'll need on each cow.

[desert cipher]

hem wouldnt broadcast and reply system work for that?

[eternal crow]

I thought I saw somewhere...maybe on instructables, or another site of a way of mapping it. But I never followed up since I didn't know if it was even possible.

[rough edge]

?showtimes

[worldly shale]

Desk of Ladyada - Random hacker times
JP's Product Pick of the Week - 4pm ET Tuesdays
3D Hangouts - 11am ET Wednesdays
Show & Tell - 7:30pm ET Wednesdays
Ask an Engineer - 8pm ET Wednesdays
John Park's Workshop - 4pm ET Thursdays
Deep Dive w/ Foamyguy - 5pm ET Fridays
FoamyGuy's CircuitPython Stream - 11am ET Saturdays

[paper iron]

Can I put 2 headphones outputs into one input I wanna connect my PC and ps3 to the one set of speakers but I'm worried having 2 outputs on one line will damage a sound card somewhere I should probably run my ps3 into my PC though the line in instead of having 2 audio outputs going into one input or is that fine

[violet torrent]

I'd probably suggest using some sort of mixer for that, just to make sure

[paper iron]

Yeah I kinda guessed as much doesn't make sense set up wise tho I'll figure sum out

[hearty karma]

Yeah, a passive mixer made of resistors would likely be sufficient.

[delicate quarry]

Not directly. Usually you would use a mixer for that, but if you know your way around some analog circuits, it may be possible to build a summing amplifier circuit to passively mix two inputs.

[paper iron]

I don't have any resisters or rectifiers and even if I did my knowledge really is quite limited

[delicate quarry]

Oh, then here's an instructable to guide you step-by-step. https://www.instructables.com/Making-an-Audio-Mixer/

[remote pike]

I have a project (finished) using circuit playground, I hadn't touched it for a few weeks and when I fired it up it wasn't lighting up all the neo pixels, I suspected a loose connection BUT it turns out reloading the code made it work... is this something that happens with the circuit playground if its left without power for a long time?

[upper coyote]

That shouldn't usually happen after a few weeks, a few years maybe, but not weeks. By "hadn't touched", did you mean it sat there powered off, or it was powered and running, but nobody was paying attention to it? In the later case it might have been some software resource exhaustion.

[mild sinew]

Does anyone know why my past two orders got cancelled?

[solemn field]

Order support is not something we can provide on Discord. Please email [e-mail] for issues with orders. Thank you.

[mild sinew]

I already did

[solemn field]

Unfortunately, we have no one with access to or control over orders on Discord. You could try posting on the forums, but I believe the response there will also be to email support.

[mild sinew]

Alright, np

[minor crag]

anyone know of any dev boards available with the STM32H7 chip?

[vapid needle]

https://www.adafruit.com/product/5032?gclid=Cj0KCQjw1ZeUBhDyARIsAOzAqQK8lx0tymtZNcwhBWWD7ZWT1l_MRKaeym8gQGRTl964nR9imEsAuaIaAnT6EALw_wcB

[pulsar shale]

Can I use my U2F Zero (like a Yubikey) for multi-factor authentication on adafruit.com?

[karmic obsidian]

WE ARE LIVE! ASK AN ENGINEER! https://youtu.be/bvvmqmwVcrk

[thick prawn]

I'm pretty proud of how much I've been improving at math

I've found a genuine love for it, and I'm finding myself making connections between what I learn with no guidance

In precalculus class I learned about the binomial theorem, and I realized it's what I needed to prove the power rule, and I solved the limit myself. It's not much, but I'm proud I'm becoming able to connect things like this

Such a great feeling

[steady gulch]

yeah Maths rule ! 🤘

[steep yacht]

Maybe not fresh or recent but question: Why the support of CircuitPython on ESP8266 was dropped? Is it due the low performance of the ESP8266 and low memory?

[steady gulch]

at the time Circuitpython moved to only support boards with native USB

[steep yacht]

Ah, that makes sense

[thick prawn]

I taught myself good chunks of calculus 1 2 and 3

I’m in precalculus in school, but it was too boring. My dad taught me you get the most out of things when you chase them yourself, which definitely rang true this time

[slim warren]

does anyone have experience with the clone versions of the MAX6675? Specifically, have you had any issues where I should avoid buying it?

[steel needle]

But what does an adafruit taste like?

[inner linden]

I somehow managed to pass enough classes to get a degree in math and computer science, LOL.

[rocky junco]

This sounds like a really cool concept. To save battery even more, collar pings for a GPS location at timed intervals instead of all the time and if close enough to a WiFi AP, uploads to internet/local network.

[outer brook]

Does anyone have a favorite JPG to Bitmap conversion tool? I'm using cloud convert which I have successfully used for other things in the past

[woven crown]

Hello, what rfm is on this board?

Rfm96?

[delicate quarry]

Could be rfm95 or rfm96, I think they use the same pcb for both modules…

[steady gulch]

on the pictures the 95 is green and the 96 is blue, but 🤷 isn't it written on it ?

[delicate quarry]

Do the different color modules distinguish the module chipset?

[steady gulch]

and the 95 has writings on the shield

[delicate quarry]

Most likely a 96 I guess

Yeah the rfm95 has fcc certification info on the metal shield

I guess the rfm96 doesn’t because 433mhz isn’t a license free band in the us so US products would use the 95.

[woven crown]

no, it isn't written

[shrewd arrow]

Hey everybody! I'm trying to connect my adafruit Rp2040 to my computer but it won't seem to pop up , is there anything I'm doing wrong?

There is also a red blinking LED labelled 13 in the corner I don't know if that is a part of the problem

[random cypress]

Any image editor. E.g. GIMP, MS Paint, etc.

[steady gulch]

hi, what are you trying to do ? have you looked at the guide ? https://learn.adafruit.com/adafruit-feather-rp2040-pico

[shrewd arrow]

Hi thank you I actually did solve the problem but I appreciate you linking the docs

[outer brook]

Oh I can just do it in InkScape?

[lost lily]

I find online sites pretty sketch lol
I use imagemagick, like ffmpeg but for images

[random cypress]

Inkscape is a vector graphics editor, you need a raster (i.e., non-vector) image editor

Since jpeg and bitmap are raster formats

[shrewd arrow]

Hey y'all I'm trying to turn on this display and have it say hello world but this red light keeps blinking and nothing is happening has anyone used the rp2040 on a display before ?

[hearty karma]

I use GraphicConverter. It's great for bulk conversions, generating file icons, etc.

[hearty karma]

It looks like those header pins aren't soldered, so they're likely not connecting reliably enough to control a display.

[main hemlock]

@shrewd arrow ^this, you have to solder the pins

[hearty karma]

Or use non-solder approaches such as "hammer headers" or pogo pin clips

[outer brook]

Thx!

[outer brook]

Any idea if it can do SVG to DXF?

[outer brook]

Ah it's Mac only

[hearty karma]

I just noticed these show up at a surplus vendor: https://www.goldmine-elec-products.com/prodinfo.asp?number=G26442

[mental mica]

Thanks for the notification! Unfortunately, I’ve already got drivers & what I need is a controller

[pine igloo]

Hey guys, how do you like my raspberry pi setup?

[gloomy mango]

👍

I'm going for something a little more discrete for my Pi Zero 2W.

[pine igloo]

cool

[gloomy mango]

I do want one of those.. when I can order a Pi4.

[hearty karma]

I normally use an MCU as a controller

[mental mica]

that's kinda my problem from earlier-- I need to clock out 72 bits of data 8 times just to scan the display once

doing that constantly is a lot of work for an MCU that should ALSO be doing FFT

that's why I talked so much about needing a controller IC

[pine igloo]

ok

nice

[gloomy mango]

I got my hands on a Pi Zero 2W, so I'm going to install that into a keyboard.

[pine igloo]

good idea

let me guess... your gonna make a bluetooth keyboard*?

[gloomy mango]

I thought so.. 😁

I've got an IBM SK-8815, which has 2x USB ports.. so it will be easier to connect a mouse.

[pine igloo]

nice!

[gloomy mango]

Just need to figure out the wiring and retention mechanism.

[hearty karma]

Hmm, I would look at ways of offloading that work, like if the MCU has hardware SPI and the driver chip can work with SPI, or if the MCU is something like a Propeller or RP2040 that has auxiliary logic you can program to do stuff independently.

[junior pivot]

Are you worried your Raspberry Pi might get slightly warm?

[pine igloo]

nope

it's probably freezing right now🥶

[surreal pond]

Freezing🙃

I keep my house at like...62

Rpis will never get warm in my house

[glossy totem]

that's terrifying

[wise sand]

are there any diagrams/schematics available for this connector:
https://www.adafruit.com/product/5358

I found diagrams for the 3 and 5 pin version but not 4 pin

and the 4 pin looks different from the 3 and 5 pin ones

[pine igloo]

GUYS I GOT THE BEST IDEA!

I'm gonna make remote controlled car with my rpi!

[mystic quest]

Sounds fun, you get to choose everything for example how it is controlled like bluetooth or wifi or something else. I made a wifi one before and I gave it a camera.

[pine igloo]

yeah I had the same idea

I'm gonna look for some tutorials to get a good foundation first.

[mystic quest]

That's a good way to proceed

This is what I used to control the motors, I like it because the extra pins are broken out so it's easy to add more hardware
https://www.adafruit.com/product/2348

[pine igloo]

yeeesh that is COSTLY OMG

but I might try it

[mystic quest]

It has good example code so it doesn't take long to figure out the motors.

Whenever I'm looking for examples of a project, I usually go with the one whose code I can best understand.

[pine igloo]

That makes sense

[pine igloo]

I don't have a 3d printer but I can use pcbway's

for a small fee

[pine igloo]

speaking of motors can you guys explain to me why these starts at 20-30$: https://www.pololu.com/category/172/6v-medium-power-mp-micro-metal-gearmotors ??

can I get something better for that price or should I just eat the bullet and design my tankr robot around them since they soldered to the low-spec board?

they seems to include the gearing/hall sensor/rotary encoder in the brass part

[hearty karma]

I think the ones with the encoder have it at the other end of the shaft (one popular option has a magnetic disk mounted on the shaft)

[pine igloo]

but they are just brushed motor and low power ones so seems to me they are really really expensive and are being sold with a huge markup

similar brushed motor without the parts in brass costs less than a dollar

[hearty karma]

Technically, they're brushed motors with gearboxes. They have an assortment of different brushes (carbon, precious metal, etc.) and winding arrangements with different efficiencies. I would tend to believe these are higher quality motors than the cheap ones you refer to, but I can't be sure.

Carbon brushes on the left, precious metal brushes on the right

[pine igloo]

Since this might sounds like an X-Y problem, just to give context to everyone, this is from a smart tank kit that costs me 180$. So I'm trying to find out how much I actually got because so far I have 12 parts on it worth 1$, those supposedly good 25$ motors (2 of them) , and a primitive cpu (atmel 32u4) that costs 3$

[hearty karma]

Those appear to be "oilite" style sleeve bearings.

[pine igloo]

So I'm trying to figure out how bad I got "scammed" and what I can reuse or not

the board have most of its pins used by on-board sensors too, so I only would have 8-9 gpios left on the atmel 32u4

if I uses these motors

[hearty karma]

The main differences I see in small DC motors are efficiency, lifetime, and mechanical rigidity. Which of these are important to you depends a lot on your use case.

[pine igloo]

I can post a pic of the pinsout if needed (it's going to be my next question anyway)

[pine igloo]

Well I just want to know, if for a tank, it's it likely that the price being shown for these motors have a correlation with their quality

or if a 1$ motor could replace them

[hearty karma]

Amusingly, I'm currently building a project using inexpensive DC brushed motors, but I'm driving them with an AdaFruit motor wing, so I just need two GPIO pins to send I2C commands to the motor driver.

[pine igloo]

I have absolutely no idea how to tell if they are quality motors to figure out if I got my money worth

If I knew I got 50$ of motors that are actually quality for the price I'd feel less bad about paying 180$ for the whole thing

And would be less angry at myself for the purchase

[hearty karma]

Again, it depends on your use case. If you need the gearing for torque/speed reasons, you'll need gearbox motors. If they're going to run frequently, you'll want motors that don't wear out too fast. If they'll be supporting mechanical loads on their shafts, you'll want motors with good bearings. If they'll be battery operated, you'll want high efficiency motors. And so on.

[outer brook]

If you run one of these micromotors at 4 or 5V, it should just run slower right? Sans encoder

[pine igloo]

well my use case is that I want to improve what I got so it meet my expectations

ie: being able to map a room by having range sensors or ToF sensors, being able to tell the color of a tape so I can do a track with actions depending on the colors

I clearly won't be able to put a pi and a camera on there because the tank is already slow and would get even slower with the extra weight

[hearty karma]

You can do a basic test for mechanical rigidity by just wiggling the motor shafts. If they're loose, it's probably not a high quality bearing. You can also measure motor torque, speed, and efficiency. Lifetime and other build quality is a little tougher (I'll often take motors apart to evaluate their windings, magnets, brushes, commutator, etc. but some motors won't work as well (or at all) after being reassembled (if they can be reassembled with the tools and skills I have)

Heh, when you said "tank", I read it like "fish tank" and was thinking you wanted motors to pump water or something. I only slowly realized you meant a tracked vehicle!

[pine igloo]

I can't remove the motors thought because they are dangling from metal wires soldered on the board and next to a hall sensor fused to the board

so if they move the on-board stuff will probably not work anymore

[hearty karma]

So I'll just reiterate that I end to consider Pololu stuff to be decent quality (I buy a fair amount of stuff from them, and they're nice folks as well)

[pine igloo]

so the idea is that I removed what I didn't like / didn't meet my expectations. The last issue is wheter the board is worth keeping as well since it comes with the motors

despite the lack of capabilities on it

I'm going to need to add at least 4 sensors that can sense the color of a tape under it, and possibly a rotating ToF sensor or a ultrasonic for each direction on a 2d plane

[outer brook]

Thoughts?

[pine igloo]

I'm not sure what you mean, the battery box is 4 AA batteries so it already run at 4.8V instead of 6V so it's slower already

I'm confused from mentionning encoder since they are built-in and the speed of the motors shouldn't affect it?

[outer brook]

Ignoring the voltage required by the encoder

[hearty karma]

Yeah, DC motors will normally run fine from a range of voltages, just at varying speed

[outer brook]

Perfect

[hearty karma]

The encoder is presumably powered by the logic supply, so as long as there's enough voltage to operate the CPU, the encoder should be fine.

[pine igloo]

Since we are getting into the subject, these are the pins taken by the motors and associated control (in pink)

so another alternative would be to put a more capable board and only send motor related command to the vanilla one

but that implies adding weight, level shifters and a 2nd power supply etc

Even if I removed the lcd and the front things my understanding is that for these, even if they seems free, they are connected to things printed on the PCB

so I can't use them because I can't remove their connections

The 3rd alternative would be to just donate it/recycle it and start my own from scratch.... 😦

what do you think ?

[hearty karma]

I'd just hang more stuff on the I2C bus

[pine igloo]

Yeah control is still a problem, an frsky neuron esc uses 5A and that's not even including the RC receiver. So so far i'd have to use a remote/cheap ir sensor

and if you wonder why frsky OpenTX neuron ESC it's because it's completely open(+ source of the firmware) and use an arduino based usb programmer to program it...

so I avoid the proprietary ESC from the r/c world

That's the third issue with the smart tank, I have to make a pre-programmed path kinda like LOGO turtles in the 1980s

anyway I think I know what I'll do, reuse what sensors I already have for this small robot

afaik I can't use any of the sides pins since they are all for onboard stuff, but I still have 6-7 I can use including UART

then use the motherboard style standoff to add a more capable board to get better options

And in the meantime prepare for the big wheeled robot project that would have 2 lipo batteries and could power those 200A brushless motors and openTX receiver/ESC. I'd even have the bonus that it could carry the zuma onboard for stealth/smaller operations and send it commands

[hearty karma]

Using 5A sounds like a power issue, not a control issue (or are you thinking of switching the power to the ESC?)

[pine igloo]

well with 4AA batteries I don't see how I can power the 5A/6V ESC for long, and there isn't enough space for lipoly or more AA batteries

and I don't think those micro motors can handle much more weight either

so I have a big space/power limitation that I wouldn't have on say a 1sf custom chassis with 2 lipolys if you see what I mean

[verbal aspen]

Yeah, an AA cell will not be happy with a 5A load.

[pine igloo]

the best option would probably be to start on a much bigger robot with the solidworks license so I can 3d print the parts etc

but this is 800$ already for the lidar, the motors, the 2 lipolys battery with a charger, the weather-proof enclosure the pi4 and the camera...

[verbal aspen]

The Solidworks license alone would be much more than that cost, too. 😅

[pine igloo]

nah it's 99$ per year for a maker license

which is almost the full version, my makerspace has it for them

and I just did 2h of training on it seems very capable

[verbal aspen]

Oh, the "3DExperience" web version? Haven't tried that.

[pine igloo]

license terms are: "meant for personal projects and non-commercial use. Per our terms and conditions, you may sell items you make for a profit up to and not exceeding US$2,000 a year"

yeah, you can still save on the computer even if it's the web version and it has a connected module so I can access my parts from the makerspace if both of us has it

which would be the case if I had it (and simpler than storing it on their computers)

[hearty karma]

No, AA cells can manage maybe 1A. If you need more current, you'll need a more capable source of power.

[pine igloo]

if you have 5 AA batteries in parallel don't you have 5A ?

[hearty karma]

You can join EAA for $40/year and it comes with a Solidworks license. I'd do that, but it's DOS-only and I don't have any DOS machines.

[pine igloo]

Whereas Voltage is added in series

[hearty karma]

Yes, 5 AA cells in parallel could yield 5A (at 1.5V, which is likely not sufficient for that ESC)

[pine igloo]

EAA annual membership is half of the 99$ anyway and there are very few chapters in Canada. Not sure what you mean by DOS-only, hardware requirements seems the same. But at the end of the day it would be the same cost and I wouldn't be able to do anything EAA related

But such an alternative is very interesting if you want to fly drones in Canada because Aeronautical clubs have their own laws which predates canadian drones laws and have private airfields

[hearty karma]

I mean Solidworks does not run on BSD, Linux, or MacOS

[pine igloo]

I know it's a side-topic but aeronautical club is a very good deal if you can't figure the drone laws/find a place to fly one

[pine igloo]

I'm on windows, my linux laptop is too underpowered to even works tinkercad anyway

and since the maker space I mentionned is only open 5h a week I'd maximise the time to do 3d printing

so it works for my constraints but probably wouldn't for most peoples

If someone want to read more about the exemption from drone laws I mentioned above in Canada: https://tc.canada.ca/en/aviation/reference-centre/exemptions-canadian-aviation-regulations-cars/exemption-part-ix-canadian-aviation-regulations It's for members of the model aeronautical association of Canada which have their own private airfields and airspaces around it so they have juridiction to decide on licensing and requirements to fly drones on their private properties

like the one close to me has a 11 miles airspace around their airfield

hey

Biggest difference in MAAC is: to fly above 250g you don't need a drone license, just to arrange a flight plan and spotter (another MAAC member)

I have been brain storming some ways to make my chassis for my car

but I'm a little stumped when it comes to getting my raspberry pi on my car.

should I use stand offs?

[pine igloo]

I'd strongly advise starting from an R/C chassis or a 1 or2cf weatherproof enclosure if you don't have one

and yeah that is what I advise, use a plate and standoffs

whats a "1 or2cf weatherproof enclosure"

you'll probably need to bolt the standoff and use a sprray on anti-vibration/anti-unscrewing compound to the screw too

1 or 2 cubic foot

ok

wait

If you use a pi because of the power it uses it kinda implies you'll use lipoly and those have a good size

I have been thinking of 3d modelling my case

and also that you will use big devices like a lidar or camera

with tinker cad

[gloomy mango]

Yarp.. best way, especially if you have a 3D printer.

[pine igloo]

I doubt 3d materials is solid enough for a chassis of that size

3d materials in the range of entry-printer that most peoples here can afford..

[pine igloo]

oh, well what materials would you reccomend?

[gloomy mango]

Still good for prototyping

[pine igloo]

there will be lot of vibrations and if you use a 1/2cf chassis that implies 2-4 inches wheels which mean some good motors

[pine igloo]

right

so probably a final product that would be a few pounds and in the range 20-30mph range

if your 3d printed chassis collide with something at this speed it will break for sure

so wood?

and the torque from the components screwed in will probably shatter it too

wood, thin hard metal like extruded aluminum, thick hard specialized plastics etc

[gloomy mango]

Only use wood for a chassis if your name is Morgan. 😅

[pine igloo]

Morgan?

wood can't really be 3d printed well or use modern fab machines either so you'll have to use classic tools/methods AFAIK

[hearty karma]

You can print pretty solid stuff with ordinary PLA. I'll usually use like 25% gyroid infill and several perimeters and I can bolt stuff to it and abuse it and it'll usually be fine, as long as I arrange my design so the forces don't concentrate on the weaker joints.

[pine igloo]

because obviously I don't mean balsa wood or MDF here not hard enough

hey wait

maybe ill buy a kit first

[gloomy mango]

Morgan cars are famous for wooden chassis.

[pine igloo]

then ill build it and get a good foundation

kits start a 500-600$ for a chassis of that size/hardness

I found a cheap one from the company Freenove

if you want I can provide you a link to semi-open 12000$ one with design document just so you get an idea of the enclosure/tools/materials used in serious robotic projects which I use as a guide along with the videos from youtube by dronebot workshsop and other suggestions from ishiro in #help-with-robotics

[hearty karma]

Quit being discouraging. There's plenty out there that can support a pi that doesn't cost hundreds of bucks.

[pine igloo]

yeah I already found some

https://www.amazon.com/Freenove-Raspberry-Tracking-Avoidance-Ultrasonic/dp/B07YD2LT9D/ref=sr_1_4?crid=398NJRDWY4ES6&keywords=Freenove&qid=1653250336&sprefix=freenove%2Caps%2C67&sr=8-4

that was the car I found

ah yeah you should have mentionned you didn't need weather-proof or 1cf when I mentionned those... otherwise the rest of what I said is useless

[gloomy mango]

There are plenty of modern tools for use with wood, including CNC... but, ehh.. I wouldn't.

[pine igloo]

for me with my small apartment if I can't take it outside it is useless

I won't have enough space to enjoy it

oh well I'm just getting started

so I wasn't worried about the weather

[pine igloo]

the x-carve CNC from my fablab and their other one that are in the 4000-5000$ range can't handle wood thicker than 0.4"

[gloomy mango]

Ooooffff

[pine igloo]

I mean hardwood here obviously like oak/pine

[gloomy mango]

My cousin built better for less. 😅

[pine igloo]

when I asked they suggested I use their stand linear saws/jigsaws/wheel saws instead of the CNC

[gloomy mango]

Yeah, very much depends on the job, innit.

[pine igloo]

@pine igloo these are great to learn, but you just need to understand the chassis and parts are the cheapest of the cheap

ok

but ya know you gotta learn first

There are a kits like these and they all use the exact same plastic wheel that last a few months according to the reviews

[gloomy mango]

I'm planning a not so small RC car build myself, but I think that will wait..

[pine igloo]

sure but it's a bit like building a computer, you can learn AND have an expandable chassis too...

[pine igloo]

yep

[pine igloo]

ok

so how do I get started

the biggest constraint on such a project is the chassis and motors. When you add weight the performance of the motors get lower

right

chassis limit space, motors limit weight

components limit complexity

sure you can build up but personally I don't think a rolling skyscraper is a beautiful r/c car

what

nvm

[pine igloo]

well I'd get an arduino one, bare minimum thing so you will know what the like or not for as cheap as possible

for about half the price

an arduino car kit?

I really regret getting a zumo 32u4 because I didn't understand what the sensors did exactly and the chassis is very small which really limit expansion

[pine igloo]

yeah

starts with the minimum to help you figure out what you want

besides if you build something bigger ... I mean camera/lidar already costs more than these basic kits...

https://www.amazon.com/Freenove-Compatible-Avoidance-Ultrasonic-Bluetooth/dp/B07YBQ73CH?ref_=ast_sto_dp&th=1&psc=1

how about this one?

Honestly I think they are pretty much the same. In Canada elegoo are pretty good at making arduino boards quality wise so I'd go with them, but I don't know the US brands

ok ill try ellego

This is what I'm going with after learning of the limitations of my first kit:

elegoo*

Hopefully I can carry my first kit inside it as well aand deploy it and send it command, that would be cool so it wasn't a complete waste

You can also check the manual of the elegoo fully (full documentation) before you decide to get it

some of those kits I couldn't even find more than 4 pages of documentation

bought solidworks 😦

[mental mica]

is it carbon brushes that give cheap DC motors that distinctive smell?

[hearty karma]

It turns out the carbon brushes are in the fancier motors. I'm guessing the cheap ones, it's either a little ozone from the sparking, or small metal particles evaporated from the brushes and commutators.

[pine igloo]

doesn't smell like ozone though, more like burned electronics

my guess has always been that since they are cheap they don't come with the option of having washed the chemicals away or the cleaning bath used on the recycled metal

whereas if you pay a bit more they had the step where they blow air on them to chase away the chemical smell

and if you pay 2x a bit more, they test them

Hello just joined the server because I need help with a problem on cicuitpython

anyone can help please?

just nopticed the text chat for that. nvm

[pine igloo]

also before I forget , the hardware checker will fail for most peoples here because it check for a professionnal workstation with nvidia quadro pro or similar but Ive seen the current version run on an onboard graphic card

So I'd make sure to have a good windows PC with a good graphics card before you spend on it. It is a 3d modeling software after all

And I mean after all it is an industry tool that just happen to have an hobbyist license. So of course they check for a certified professionnal workstation usually used in the industry at machine shops and not a hobbyist machine

[karmic obsidian]

The Desk of Ladyada - S3 & Sample Sunday https://youtu.be/JBo326sv-_Y

[prime adder]

Wow are my scopes ground probes connected to earth ground

Googling seems to say yes

Which explains some weird thing I was seeing… since I was shorting a bunch of stuff!

If that’s the case I’m glad I made this discovery before destroying stuff 😆

[astral lily]

You can easily find out by using a multimeter to test it. Continuity mode, one probe on measurement ground and the other probe on earth ground.

[inland pelican]

Hello! Did someone use powerboost 500 basic for powering rpi zero from LiPo cell? When i try this there is a hum noise and after few sec rpi zero green led is off.

[carmine plover]

Hey I don't have idea about this community, I just Redirected here by Python's Resources Page! Can you guys please figure out about this ?

[steady gulch]

figure out what ?

were you like auto redirected by a page ? what page then ? or is it about something else ?

[pine igloo]

have anybody here ever worked with chromium-browser on raspberry pi before? Having a really simple yet confusing problem,
So the problem is when i run the following command
chromium-browser --disable-translate --incognito --noerrdialogs knipklok.nl/appointmentv2.php?boxid=000&boxcode=0000000
in the terminal, it does open up the chromium with that URL but it only passes one (first) parameter to the browser
So like after executing that command, when i see the URL of the browser that opens up, That URL looks like this
knipklok.nl/appointmentv2.php?boxid=000

[steady gulch]

put quotes around the URL

the & symbol has a special meaning in the command line

(running a command in the background)

for example see: https://linuxize.com/post/how-to-run-linux-commands-in-background/

[pine igloo]

Ah i see, Thank you very much

[mental mica]

I wonder if an FPGA would be good there

if nothing else, it's an excuse to finally learn FPGA stuff-- it's next up in my CE Major

[hearty karma]

Yeah, an FPGA would be a good choice: they're good at that sort of thing.

[ruby dragon]

YO im trying to make a keyboard input with a trinket m0 (SAMD21) and for the life of me, I CANNOT find the dam keyboard library in the IDE

[eternal crow]

Question on the small gps board, is it possible to setup multiple batteries for the gps to pull from?

[pine igloo]

Hey guys which electronics car kit should I buy?

https://www.amazon.com/Freenove-Raspberry-Tracking-Avoidance-Ultrasonic/dp/B07YD2LT9D/ref=sr_1_3?crid=22732K9IJ1MJB&keywords=Freenove&qid=1653328447&smid=AV3WCPW70PEXC&sprefix=freenove%2Caps%2C70&sr=8-3 this one

or

https://www.amazon.com/Freenove-Compatible-Avoidance-Ultrasonic-Bluetooth/dp/B07YBPTXHG?ref_=ast_sto_dp this one

@solemn field can you help me decide?

[delicate quarry]

The former requires you to provide your own Raspberry Pi, so if you don't have one on-hand for this, definitely go with the latter.

[pine igloo]

I have one

[delicate quarry]

Otherwise, it really comes down to Arduino vs Pi. The latter is better if you're interested in hardware mods and microcontroller development, while the former is more open to advanced software modification and development.

[pine igloo]

oh

well I do need two litium ion batteries for the raspi one

and they are really costly

[delicate quarry]

You won't be able to play much with things like image recognition on an Arduino, for instance.

[pine igloo]

yeah

well I'm OK when it comes to coding but I think the raspi one will be too complicated

and plus ill get TWO arduino's!

[delicate quarry]

Both look like fun kits with solid educational offerings, but the biggest difference is what you want to do with them AFTER you build said kits. If you just want a toy to drive around, the Arduino kit is definitely more cost-effective, but if you want the benefit of an onboard Linux OS, the Pi can do a lot more without too much extra hardware.

Two arduinos?

[pine igloo]

yep

[delicate quarry]

Oh, the remote is Arduino-based too huh

[pine igloo]

I want to learn and build off of the default

[delicate quarry]

Interesting.

[solemn field]

Please do not ping admins or moderators unless you are reporting a moderation or Code of Conduct issue. Thank you.

[pine igloo]

oh

ok

[gloomy mango]

Piduino

[solemn field]

Hello, members of the Adafruit Discord community. We have made a change to the name, and therefore the scope, of this channel. It is now the #general-tech channel. Please try to stay within the scope of the channel and keep the discussions to general technical related. If you have any questions, please post your question in #help-with-community or post there to ask for a private thread to be created if you’d rather not ask publicly. Thank you.

[ruby dragon]

print("Hello, CircuitPython!")
really no way to change baudrate?

[forest vigil]

You seem to have a lot of preconceptions as to what CircuitPython is supposed to be. I get it. There's a lot of adjustments going from "big hardware" Python to "little hardware" Python. I have been frustrated by its limitations too, but there's no call to insult what is really quite a capable environment and toolchain.

[ruby dragon]

you know I saw people suggesting this for driving a display, and it cant even change the buad rate . I have no idea how this language is capable when it cant even support interrupts

Interrupts are not some super advanced use case either, any reliable code would be using them for many operation

[ruby dragon]

also what do you mean by the terms little and big hardware? And if these are industry terms are they used often? This is just coming from my curiousity, I do love to learn new things

[outer brook]

To my understanding, true C style (and older) interrupts just aren't possible in Python anyway. Pythonic interrupts are obviously on the developer's radars ( see https://github.com/adafruit/circuitpython/issues/4542) for now, asyncio exists.

[hearty karma]

As far as I know, it can change the baud rate, but usually I'm talking to it over a USB link, so it's a moot point.

[outer brook]

Yeah I'm not seeing really anything that says you can't. Maybe there's a specific place?

[ruby dragon]

This is clearly a less developed possibly slower language all the libraries in new stuff are being built for this I find that to be really annoying for those who are not learning but actually using these boards or learning and using these parts

I would like to know about any advantages to language has though

[outer brook]

You're free to research them.

[ruby dragon]

So far my research has gotten me too easier to use

I don't even believe that

[random cypress]

@ruby dragon, if you want help with something, ask for it. Please don't dump non-constructive criticism, no one on this hobby-oriented server wants to receive that.

[ruby dragon]

This is not a help Channel

[outer brook]

The beauty of an open source project is you are also free to add what you would like.

[forest vigil]

I have probably been programming computers since before you were born, so I may have a bit more perspective. I invented the term big hardware and little hardware for that one comment. For this discussion "Big Hardware" = 64 bit or even 32 bit instructions, Secondary memory in 100Gigs or more, primary in Several Gig or more, and perhaps 4 or more core processors. Like your current desktop or laptop. Little hardware has 32 bit or 16 bit instructions, Secondary memory of Several Gig, Primary memory of a couple Gig if you're lucky. For reference, when I started programming we measured our memory in Kbytes and had an 8 bit instruction width.

[verbal aspen]

Kilobytes? LUXURY! We used to measure our storage in cards, and our memory in magnetic cores! 😉

[forest vigil]

If you are going to be working with interrupts, Python is probably not the language you want. For high-performance embedded work, stick with C and C++.

[ruby dragon]

unfortuneatly I really dont have the time and will to learn how to create HID reports from scratch, and the only lib I can get working for HID is the circut python one

but in the future though I will 100% heed that advice

[forest vigil]

CircuitPython and HID is great. I use it for a password typer and mouse jiggler. On several boards.

[ruby dragon]

yeah its really good

[forest vigil]

@ruby dragon As a general comment though, carefully read the learn guides and documentation Adafruit has bent over backwards to supply. It is densely packed and covers so many board variations, sometimes it can be tough to glean what applies to your particular case.

[forest vigil]

I don't recall having a problem changing baud rates when I needed to.

[ruby dragon]

ok yeah, so that was more of a question that I made it out to be lol

[forest vigil]

I am only a few years shy of having to program using hollerith cards. (magic marker diagonals across the top, lest your drop your deck?)

[ruby dragon]

HEY i used cards too

[forest vigil]

I did, however, use Teletypes for several years. 300 baud terminals? A luxury!

[ruby dragon]

I used cards on my consoles

PS2 FTW

[forest vigil]

Cleaned a mouse's ball?

[verbal aspen]

Same. Cassette tapes were the oldest storage I actually used, heh heh.

[hearty karma]

Same. Started with the front board, fully populated with 576B of RAM.

Now I'm in the process of writing a Python program to laboriously post-process the audio from the original cassettes and attempt to recreate the original data, using a variety of techniques including leveraging the built-in checksum of Motorola S-records to do heuristic tie-breaking of ambiguous data

I do use "big" hardware (2.2GHz 64-bit machine) to emulate a teletypewriter for said "small" (1MHz, 8-bit) hardware 🙂

[forest vigil]

8080? Z80? 6502? 6800? Oh, you did say Motorola, right?

[hearty karma]

Yeah, 6800

[pine igloo]

Hey all,

Wanted some of your opinions/help.
So here is what I wish to do.
Say I have “x” script that is meant to be constantly running.
How can I check from “y” script if this program is actually still running?

Considered maybe every minute or so it writes the current date and time to a file and then I can check that the time is less than five mins ago or something, however I will be having tonnes of scripts and that could cause issues.

Thanks all!

[solar pagoda]

@forest vigil @hearty karma This is how we got our software before pc's were pc's

[jade dirge]

I had a teletype printer with a punch tape reader but I never used the reader. First PC had 8" SSSD disks.

241k per if I recall

[astral lily]

On Linux I'd use "ps -A"; other operating systems, I'd look for the equivalent.

Is there a chart/diagram somewhere that lists all the different Adafruit product lines/terms and what they mean/are designed for? Feather, Wing, Stemma, QT, etc.

Usually there's some detail on individual product pages but it would be nice to see it all in one spot with the intent behind it all.

[hearty karma]

Many versions of Linux and BSD have system daemon support to run things automatically and restart them when needed.

[hearty karma]

You could make those today, if you wanted: https://www.solid-merch.com/flexi-discs/

[hearty karma]

One shortlived idea was printing machine readable data in the magazines. One of the implementations was the Cauzin SoftStrip, which had an accompanying reader module to scan the data. https://www.insentricity.com/filedb/4/5/11654.png

[forest vigil]

Be careful what you ask...

[verbal aspen]

Heh, that was a big step up from typing in code listings manually from magazines. I was thrilled when they started using checksums so you could be sure you didn't accidentally drop a comma. 😅

[mental mica]

fancee github feature: https://github.blog/changelog/2022-05-19-render-mathematical-expressions-in-markdown/

they just added the ability to do latex-ish math equation rendering

(AKA: all PRs must now be accompanied by a mathematical proof)

[main hemlock]

@nimble prawn ^^

[drifting ice]

...when you manage to properly apply thermal paste after cleaning off the CPU without making a mess, followed by finding the missing screws, reassembling the laptop, giving it a storage upgrade, and cleaning it of any dust successfully, finally turning it on with a full charge to boot, only to find that the touchscreen somehow got cracked.

-_-

[pearl frost]

https://media.discordapp.net/attachments/872373121292853248/978752731063910420/img_thermal_1653366041731.jpg?width=549&height=732

pretty cool what you can get with relatively affordable thermal cameras these days

seek thermal + 20$ co2 laser lens = macro thermal

[pine igloo]

which co2 laser lens ?

I supposed this is the cheapest smart phone FLIR camera ?

[pearl frost]

https://www.amazon.com/gp/product/B01EMZD2DA

you might play with different focal lenghts

then I just printed a little thing to hold that in place over the lens

[pine igloo]

and the camera? (which was the most important thing for me since pi ones only do 24x32 pixels, ie: like an old-school rpg icon...)<

I expect that is still the same. Wish they offered a 300x260 like the one for smart phone that is 200$ but for the pi

[pine igloo]

Issue is I wish for it to be within the python code,

[astral lily]

@pine igloo I would still do the same thing, the syntax may just be a little different to call the system function. A quick web search for "get process list python" returns several ways of doing this across a few platforms.

[pine igloo]

Hmmm ye maybe, will any issues be caused because I have them run off one file? (Using the threading)

that is VERY interesting. Thanks 🙂

[pearl frost]

https://www.thermal.com/

[inner linden]

I really want a thermal camera of the sort I can't readily justify the cost of

[astral lily]

Not completely sure I follow but worth a try at least?

[pine igloo]

Ye will do so

[minor hawk]

Who do I contact with problems with my store account?

[vagrant gyro]

please email [e-mail]

[minor hawk]

I have several times. I NEVER get a response from them.

[vagrant gyro]

how long ago was your last email?

[minor hawk]

About a week.

I've filled in the webforms, sent emails and no response to any of them. This has been twice a week for the last several.

The site also says try discord. So I'm here and big surprise, there is still no way to contact anyone for help.

[vagrant gyro]

hmm. not sure. the email / web form was the correct route for this type of thing.

[minor hawk]

Guess I'm stuck. I'll have to take any business elsewhere since their customer service appears to be nonexistent to me at this point.

[vagrant gyro]

let me see if i can find out anything. and will respond back here.

[forest vigil]

Common advice: Did you check your spam folder(s)?

[random cypress]

Finally!

I mean it's perfectly workable without the support, and if you're writing lots of equations you're still better off just checking in a tex file, but what can I say, I'm a sucker for latex support 😄

A lot of other programming-ish tools have had it for a while, including Jupyter (and Google Colab). Afaik (please correct me if I'm wrong), it's not a heavy lift to add latex support to a markdown renderer. Mathjax and similar sophisticated web based latex rendering engines have existed for a long time.

[devout remnant]

I am having trouble with the circuit python GPS library. The problem is in the gps.update command. On line 549 in the _parse_gsa section of the function, I am getting an error that "bytes" object has no attribute "decode" I am trying to run the "simple test" example
My setup runs the gps_echotest example fine. It outputs NMEA sentences, so I don't think it's a problem with the GPS

[vagrant gyro]

please re-ask this in #help-with-circuitpython

oh. nvm. already did.

[devout remnant]

Thanks, first time here.

[pine igloo]

Hey, I realized that I had this battle bots controller laying around doing nothing so I wanted to hack it to use as my controller for my R/C car. Can someone help me hack it?

[hearty karma]

First you should try to figure out what it's using to communicate. Many are 2.4GHz radio these days, but there are some using a variety of other frequencies, and some use infrared light.

Look for any stickers on it giving information or an FCC ID.

[pine igloo]

it uses ir

[fallow hollow]

I set up my two factor authorization with Authenticator, it took my code, set it up, gave me the authenticator adafruit account, but now it says the 6 figure code is invalid when I try to log in. Can anyone help?

I restarted my browser, (Chrome) cleared the cache, restarted phone and it still doesn't work. Firefox doesn't even recognise my name and password to get to the point of entering the authentication code.

[solemn field]

Try resetting your password. If that doesn't work, please contact support by going to https://www.adafruit.com/contact_us and submitting a request. We are not set up to provide account support on Discord. Adafruit Support will be able to handle that.

[fallow hollow]

I reset my password and it fails. I cannot submit a request by posting on the forum, the only way to contact tech, because I cannot login - because my authenticator code does not work, despite following all the directions. Any ideas? No existing posts on this issue in support.

[solemn field]

Email [e-mail]. I wasn't suggesting posting in the forums, they can't help you there either. As I said, we can't help you with account issues on Discord.

[fallow hollow]

OK. Thanks. Did not see that email address on their pages before.

[hollow meadow]

Remember seeing an EEVBlog video on the Fluke 37. Old meter that's been lurking around the lab.

Very weird form factor. Very cool though.

[pine igloo]

heheheheh

That's just because a fluke is mid-range

high-end multimeters are still big boxes

[hollow meadow]

AHHHH but this isn't a desk multimeter!

[pine igloo]

this is an example: https://cdn.discordapp.com/attachments/327254708534116352/973426034491928616/10k_multimeter.jpg

[hollow meadow]

Yee

This meter is portable

It just is shaped like this

[pine igloo]

Like I imagine a guy you brag about your 2 flukes to

And he's like this isn't a multimeter THIS is a multimeter and he pulls out his keysight 3458 🤣

The keysight is portable too I guess. Would fit my backpack 😄

But at this price it would be in a brinks truck

[hollow meadow]

I like the Fluke 37 just cause they never made one this shape. It has a stand in the storage compartment

[pine igloo]

If I carried it around

[pine igloo]

oh that is very nice

[hollow meadow]

YEAH! And it's battery operated

[pine igloo]

I bet there are even worse one too, like for testing 720KV power lines

I mean the keysight one doesn't go above 5kish volt ??

[hollow meadow]

I've only dealt with 1KV tops. Maxed out my Fluke 87V

[pine igloo]

And the top voltage gloves stops at 36KV too. What do they even use if they accidently touch a 720kv power line ?

[hollow meadow]

They usually have pole meters, idk the name of them but they're on the ends of very long poles and don't need to be grounded.

[pine igloo]

Tried to get some class 4 36KV high voltage gloves to check if my allegedly 240V multimeter can actually works at 240 V but nobody want to sell me some 😦

[hollow meadow]

Sounds like you just need a safety squint

[pine igloo]

Like I was going going to test my 240V socket by sticking the test clips in it

holding the multimeter with these gloves

just in case

They say class 00 is good enough at 500V but just wanted a bit of a safety margin

[hollow meadow]

I just hold the probes with one hand and keep the meter on the ground :p

Other hand behind the back

(NOT SAFETY ADVICE)

[pine igloo]

well it's hard to put 2 probes in 1 socket with just 1 hand

[hollow meadow]

I am good with chopsticks

[pine igloo]

I mean the 240V ones are a bit apart vs 120V

And I'm going to need safety coat that cover my whole body for relays...

just in case I accidently rub against it since you have to remove the sleeves to put them in the relay terminals

[hollow meadow]

Oh you're planning on wiring while hot??

[pine igloo]

no, but when I test it it becomes hot

[hollow meadow]

Gotcha. You can also get alligator clips for your meter.

I use those when I don't want to be anywhere near what I'm testing

[pine igloo]

and since the thing that had socket receptacles with their relays is discontinued since 5 years I have to have the wires directly in without any protection...

[hollow meadow]

Yikes

[pine igloo]

Adafruit PowerSwitch Tail I/II would have been ideal for this

[hollow meadow]

I have a lot of old 80s relay sockets somewhere around here. Never really used them much but the relays they connect to are transparent which is super fun

[pine igloo]

these two are scary especially the 2nd one

Have to remove sleeves and stick the 3 part of the wire on these terminals. Even worse with the 2nd one with them being so close etc

I can imagine the electrical noise is very high on the 2nd one, don't think anyone serious would actually use the 2nd one for an actual mid-sized workshop/automation

also where the heat goes ?!

that seems much safer than the 2nd one...

[pine igloo]

stuff like this ???

[hollow meadow]

Similar! Yeah

But not the same mounting style, I don't believe. They're more round. Not DIN rail mounted.

[pine igloo]

One that I could put a latch over that is like 1 inch would do too since there would be little wire left to brush against

but yeah a switch with the copper wires in the air, I'm not approaching that

[pine igloo]

huh why would a potentiometer come in joystick form with x-y-z axis ?!

I mean I know what a joystick is and that is probably less sensitive

But for me such a joystick is for moving spaceships in a 3d game not as a potentiometer...

[hearty karma]

Just for user interface options. Sometimes it's useful to allow someone to select 2 or more values with a single finger.

[pine igloo]

but behind the scenes it's a standard 100 to 10000 ohm potentiometer? How do you know which positions will give 100 ohm and which will give 10000 ohm (say you are using such a joystick to control how dim a led is for example even though that is overkill)

[hearty karma]

Usually you can tell by looking at the joystick how the internal potentiometers are connected. Some joysticks won't give a full range of resistance values as they're using ordinary 270° pots, but the mechanical limits only allow rotating it 90° or so.

There's also the old "try it and see" approach

[pine igloo]

ah I see 1 potentiometer per axis

[hearty karma]

I actually have some gimbal joysticks right here, as I'm building a custom R/C remote control.

[pine igloo]

I'd like one on my buttonbox/joystick project but wonder how good they are vs a gaming joystick

That is for the crane behind the tractor or flaps or attachments for a truck (like in snowrunner) so don't need to be super accurate but still

[hearty karma]

As with most components, there's a wide range of performance (and price). That's true with gaming joysticks as well (a surprising number of them are fairly cheaply made).

[pine igloo]

I guess if they don't have a ball in them or bearings they aren't that accurate/good

But still the joystick for a real-life tractor is 900$ so I wonder what it does more than a 200$ gaming one especially when it looks more primitive

[hearty karma]

You'd be surprised, some use some fairly amazing angular encoders (but they're expensive)

[pine igloo]

and I mean you don't have to precise to a mm in a real-life tractor when closing the jaws of a crane or farming implement

[hearty karma]

I suspect a tractor duty one is resistant to water ingress and vibration (and probably can operate even if there's some dust, mud, chaff, or seeds in it). We used to sell military trackballs that cost a lot of money, but they kept getting broken. We swapped them out for arcade duty units that were much cheaper, and they lasted longer. Arcade gear is designed for abuse.

[pine igloo]

I shouldn't have gone to this electronics site anyway, my wallet is melting every minute... 😦

I wonder how you put joystick and switches and other mechanical stuff back to an original position anyway

Seems like it would take powerful magnets or an independent circuit with a servo

ie: like putting this back to off when powering on

[hearty karma]

The usual approach is simple springs

You can buy things like motorized potentiometers as well.

[pine igloo]

I guess my joystick project wont be as expensive as I thought after all 😄

[hearty karma]

SparkFun used to sell these motorized slide potentiometers: https://www.sparkfun.com/products/retired/10734

[pine igloo]

• these are so cheap I'll be able to make some mistakes and figure out what specs I actually need

[hearty karma]

I like it when that happens

[pine igloo]

For the tractor-grade joystick the lowest priced one was 200$....

I'd rather have a lidar/FLIR lepton 3.5 at this price...

If you can't tell as I explained in projects early I'm trying to have a couple of cheap different MCU and lots of parts

I had to repick all the parts of my sensor box 6 times and I can't take it anymore

Don't want to be limited by a lack of parts/MCU to test thing before I buy 4-5 of each anymore...

[hearty karma]

I like being able to grab useful stuff out of a box instead of waiting for it to show up in the mail. Lately, it's been handy when I wouldn't be able to buy the boards anyway due to chip shortages.

[pine igloo]

And I mean even if 30% of the aliexpress quality stuff doesn't work (which give me soldering practice anyway) it's still much cheaper and faster than more expensive stuff

Im still waiting for it to arrive but I bought pretty much every d1 mini shield, really like the flexibility and the stacking stuff

[hearty karma]

I don't consider AliExpress "faster" (I'm used to 20-40 day shipping), but it's a great way to try stuff out, get weird industrial stuff, and have several copies of something I won't cry over if I fry it.

[pine igloo]

I mean the parts are already in Canada from aliexpress reseller at only like 30-40% markup so they get here in 2 days. Is what I meant 😄

[hollow meadow]

• have a look at LCSC as well

[hearty karma]

Ah, didn't know that was available, that's cool

[hollow meadow]

its basically the same as aliexpress but specifically for electronics.

[pine igloo]

I know they ordered 1000 of their stuff on ali express, so I know the quality isn't that good. But I mean if the markup is reasonable

[pine igloo]

thanks I forgot that one and couldn't find it anymore in the discord history search

also taiya in thailand

[hollow meadow]

(idk the full context of the convo i just saw aliexpress and know i switched to lcsc for some specific things)

[pine igloo]

bah lost the name...

[hollow meadow]

Yeah! It's owned by JLCPCB so its pretty useful. can export a BOM from JLCPCB to LCSC

[pine igloo]

the context is that I decided Id rather have a lot of common part to do projects even if they are very cheap

than wait/resdesign things 6 times because I can't find the premium parts or they are in shortage

[hollow meadow]

True! yeah, I have the curse of just scrolling through LCSC/Aliexpress and saying "ooh that looks cool" and buying it.

bad habit, but nice to have stuff on hand.

[pine igloo]

Like for these joystick project I was waiting to sign a contract to order these switches for me from an industrial resellers and etch them

whole thing for 24 buttons would have cost me like 600$

[hollow meadow]

good lord

[pine igloo]

but these 2$ rocker switches with DYMO labels will do just fine 🤣

and they look tough and industrial enough

[hollow meadow]

haha yeah I have a bag of like, 100 rocker switches from Ali, they're like 15c a pop but great for adding switches.
they're "rated" for 120v but I don't 100% trust that.

[pine igloo]

cant find a cheap blue keyswitch that is at least .5 inch thought

[hollow meadow]

hmmm

[pine igloo]

sounds like I'll have to fork the money for that

[hollow meadow]

like, a mechanical keyswitch or an actual keyswitch like a switch with a key?

[hearty karma]

I found some illuminated pushbutton switches at a surplus site, I figure I can laser print clear labels to fit under the keycaps and they'll look pretty industrial.

[pine igloo]

something like this for a switch

[hollow meadow]

(i'm gonna flip through the convo rq as well haha)

OOH!

[pine igloo]

this one is CNH OEM

with a key

Filling cabinet style key/keylock doesn't fit my need

[hollow meadow]

man the keyd switches are super cool. i put one in this stupid project where i gutted a UVC EPROM eraser and bolted it to the outside of a conduit box to make a surface cleaner

yeah, big industrial switches are expensive

[hearty karma]

I was thrilled to find the exact match for the key switch in an industrial laser at a surplus house: https://www.goldmine-elec-products.com/prodinfo.asp?number=G25165

[pine igloo]

at 30$ this is good but doesn't quit fit the looks (key is too metallic)

this is industrial grade, not really necessary for me, weaterproof, vibration proof, fire resistant 400VAC etc...

gold plated contacts , a bit too much for hobbyist

[hollow meadow]

https://lcsc.com/product-detail/Special-switch_D-SWITCH-S332-1-A3_C2981351.html

https://lcsc.com/product-detail/Special-switch_Schneider-ZB2-BG4C_C514766.html

[hearty karma]

How 'bout these? https://www.electronicsurplus.com/unmarked-ym12-switch-key-7-position-master-key-or-3-position-op

[pine igloo]

the s332 is too small, seems like 0.16 inch kinda like office filling cabinets...

instead of a big switch like there would be on a tractor/mining vehicle

[hollow meadow]

ah! forgot about the size requirement, haha

[pine igloo]

which are more around 0.5 inch or 0.6 inch diameter keyswitch

[hearty karma]

https://www.electronicsurplus.com/pub/media/catalog/product/cache/b0b14895a4add095efac0068e89cdf6b/2/0/2079-1.JPG

[pine igloo]

7 positions seems a bit overkill, cant find the radius either. But that's already better on the looks of the key

[pine igloo]

what is that? Looks like some serious electricity stuff

[hearty karma]

I love industrial looking switches, especially at surplus prices. It's available here: https://www.electronicsurplus.com/stacoswitch-im1562-switch-bank-contacts-3-position-each-dpdt

[hollow meadow]

https://www.mouser.com/ProductDetail/E-Switch/KO128E2007?qs=sGAEpiMZZMv0DJfhVcWlK6OZ1WTpuN%2FCdHn74m2KMGeDXeuY0NTzNQ%3D%3D

Wait, no, nevermind, that's not stocked.

Minimum order of qty 300 :)

[pine igloo]

If I remember one one of the manufacturer (maybe e-switch the one you linked) doesn't have any keyswitch under a minimum large order

[hollow meadow]

dang, yeah, probably this one.

[pine igloo]

whereas apem the one I put a screenshot of I can order just one (the overkill one)

[hollow meadow]

Definitely starting to see the issue here, haha. these prices are crazy. surplus is def the way to go.

[pine igloo]

honestly Im hoping to find one from a used tractor on classified or something

[hollow meadow]

or junk yard perhaps

[pine igloo]

The holy grail would of course be to find an actual used panel/membrane panel from a new holland tractor

[pine igloo]

yeah and when you look at the datasheet there are included services* then later you see it's for 50000 minimum order

so I pay about the same price as these large order but I only get 1/10 of what is being described...

Speaking of which can a hobbyist print/cut something to get a membrane keypad in the end ?

[hearty karma]

Yup, there's not a lot to it.

[pine igloo]

Would be really handy for the mods that require lot of keys to use

[hollow meadow]

A jank solution could be to just print something to recess standard pushbuttons into suchthat the caps stick maybe a mm above the surface, then apply a membrane ontop of that.

[pine igloo]

Yeah I know I could laser etch plastic buttons and use pushbottons... but I dunno a custom membrane is a life goal in electronics that seems impossible

just like flir and lidar seemed impossible 15 years ago... these were dreams for me that I never thought would happen in my lifetime...

[hollow meadow]

yeah what they actually use are called metal dome pots. that's the little bits of metal that are attached to a pcb.

[pine igloo]

back then flir wouldn't even be sold to civilian or to companies outside the security sector

[hollow meadow]

they're stainless steel and are domed to flex and make contact with exposed plates.

[pine igloo]

so only way to ever play with one seemed to go in the military

[hollow meadow]

FLIR is some crazy stuff. every day im tempted to get a phone module.

there's even phones out there (industrial phones) with FLIR built in.

blows my mind.

[pine igloo]

yeah, I like it so much it's like the sole reason I want to splurge on a robotic car...

seems like a waste without being on a mobile platform

that's how some civilians earn money as well in Canada helping search lost peoples/animals/damaged crops too (except with drones)

seems custom membrane have similar prices to PCB

[hollow meadow]

ooh?

[pine igloo]

well I mean deluxe PCB

[hollow meadow]

You can also purchase the membrane springs themselves.

[pine igloo]

seems to start at around 20$ each, minimum of 10

[hollow meadow]

Oh wow, thats not bad then.

[pine igloo]

If you don't use too much colors and use the same membrane style as the ones in kit it's not that bad

[hollow meadow]

link to the distributor you found?

I might have to bookmark that.

[pine igloo]

jrpanel dot com

[hollow meadow]

danke

[pine igloo]

theres iks a led option, metal dome etc there is also snaptron but there is far more options

and they use the quality 3m back adhesives

[hollow meadow]

that's some good stuff. never thought of custom panels.

[pine igloo]

EEVblog #1282 - Design Your Own Membrane Keypad! talks about the process

seems also it's much less expensive to order them in parts rather than buy a very big one... ie a common trap is having them surround the space of an LCD screen

embossed will cost more as well (ie: can feel the icon on the button by touch) and metal domes so it's more "clickety"

comments/reddit also say they look out for you to simplify the design so it cost less in the end

some of the companies will also print some resistors with different values so you can use analog_read instead of using several pins etc

size/# of colors are really the expensive stuff

what sucks is that in Canada these sort of stuff isn't really mainstream so if you visit a business they will have min orders of like 100000

[random cypress]

They make cable reels for big outdoor extension cords. Why is it so hard to find a smaller version of that, suitable for indoor cable management of e.g. 10ft usb cables that I want to retract when I'm not using? Basically what I want is a bigger-by-a-little version of the Adafruit wire spool set (picture attached), i.e., a rod with one spool per cable. I can DIY it but I'd rather just buy it and I'm surprised it isn't easy to find.

[mighty condor]

Hi! Any luck with the ItsyBitsy nRF52840 Express? I've built the bootloader, can flash programs (with Arduino even) but the example programs (with just ble) either behave weirdly/hang or return NRF_ERROR_INTERNAL on Bluefruit.begin(). It all runs fine if I flash the self-built S140 back on the device. Played with linker settings, which made it worse and I had to recover with openocd/picoprobe (soldering on the pads wasn't fun)

[hearty karma]

I found this at an industrial supply firm. The bars are individually removable for when I want to use the wire elsewhere or add rolls. Searches for "wire spool rack" bring up several options.

[random cypress]

Aha, the secret word was "rack"! I saw a similar thing at Home Depot, but they weren't selling it. And I didn't want to pay for the actual wire on the spools they sold, either (it was like $20 per spool). It would probably cost like $20 or less total to DIY this so I don't want to pay big prices. I'll keep looking into it, thanks!

(I don't need a wall mount and probably don't need multiple rods, I just need one rod with legs to stand on the floor and a few spools.)

[pine igloo]

does qt py esp32s2 works at all in wifi without ul antenna? cant find anything on this

[main hemlock]

there are two versions: one with a built-in antenna and one with an antenna connector. I think you know this. The latter without an antenna will have poor performance

[pine igloo]

poor performancenis fine but none isnt

[delicate quarry]

I would avoid using anything designed for an antenna without having an actual antenna unless otherwise specified. Not every device will function well, and some devices could potentially have more serious consequences. If you have enough familiarity with RF signals, you could evaluate the risk on a case-by-case basis, but I'd otherwise reconsider whether or not to use the device requiring an antenna.

https://electronics.stackexchange.com/questions/335912/can-i-break-a-radio-tranceiving-device-by-operating-it-with-no-antenna-connected

If you are familiar with RF and transmission lines, the output impedance of the ESP32S2 modules with IPEX connectors are all 50ohms, though I can't conclusively say that the QtPy necessarily matches that.

Given the antennas Adafruit recommends, though, it's probably safe to assume that's also the case here.

[pine igloo]

i got the version without antenna port

so its not designed to operate with an antenna but its still wifi

which is why im puzzled

ie 5325. . 5348 is the one with an antenna port

[delicate quarry]

Oh, the one without an antenna connector has a PCB antenna built in, so you don't have to worry about that at all.

[main hemlock]

The antenna is circled

The antenna above is way smaller than the typical circuitous trace antenna:

[delicate quarry]

Oh, that's the antenna? Did not know that.

[main hemlock]

it's a ceramic chip antenna; I haven't been able to find gain figures compared with a typical trace anetnna, but it does not seem to be a significant difference as long as both are well-designed (proper ground plane, etc.)

[uneven meadow]

yo, literally asking for homework help at this point but i have a deadline in 4 hours, why is a 5ms time constant significant in an RC circuit?

my google skills are failing me hard

[upbeat elk]

Tau = R*C. Used to calculate discharge/charge rates. Can be used to find cut off frequency

[uneven meadow]

yeee, im working in LT spice for this, but apparently 5ms tau is significant?

[verbal aspen]

Not especially... I mean, it's longer than a lot of things but shorter than other things. Not a magic constant of the universe or anything.

[icy moth]

I got the best email possible for the part shortage

The BGA version of the nRF52811 was out of stock and I got a notification from mouser they came in stock so I snagged 5 🙂

I wasn’t expecting to be able to get them until later this year

So exciting

[inner linden]

So... You were on the ball for that one.

[fading hazel]

I need help. The world is a dark complicated horrifying messed up place. Surely, someone on this server must understand what I am literally fighting against? Please don’t allow it to become fatal, there is so much more adafruit stuff I want to buy.

[verbal aspen]

Wanting to buy more stuff to hack around with seems to be a good sign to me, since it's creation- and future-oriented. 😁 Focus on the things that bring you enjoyment and which enrich your little corner of the world, instead of getting dragged down by the bigger things you can't control.

[hearty karma]

For a few dark months, I'd buy parts and amuse myself by restoring old broken equipment. It gave me something more-or-less useful to do, with tangible results for my efforts.

[astral lily]

It's hard to find retractable versions in smaller sizes because the value of retraction goes away under about 25 ft or so.

[random cypress]

How do you figure? I'm looking to not have USB cables tangled on my living room floor.

[astral lily]

Cable sizes shorter than that are typically easy to coil by hand. Also besides power/air, the industrial uses are pretty limited, which is why you also don't see many, say, retractable speaker wire spools.

There is a somewhat niche market in live events where they have portable, crank-wind spools of common cables used in that industry, such as SDI, Ethernet, fiber, XLR, or DMX cable. But I don't believe I've seen any of those with spring-return feature of the retractable power/air reels.

[random cypress]

I don't need anything fancy. The idea is that I can turn the spool instead of doing the i.m.o. finicky task of coiling the cable by hand every time.

[astral lily]

Also the slip rings for any sort of mounted retractable design will destroy anything above probably 2400 baud in most cases.

[random cypress]

I'm talking about a cylindrical piece of plastic.

[astral lily]

So not something that retracts when you give it a gentle tug or that's always plugged in at the other end?

[random cypress]

...good point, I hadn't thought carefully about that. I do want it plugged in at the other end.

[astral lily]

That's where the slip rings come in. :-)

oh they do exist though! https://www.senring.com/usb-conductive-slip-ring/single-channel/um0155.html

[random cypress]

wow nice.

maybe it's possible to use a design that's not a spool and get a simpler solution...

[astral lily]

You can do it without a slip ring, but I wouldn't expect the cable to last more than a couple dozen uses in that case.

[random cypress]

yeah, without a slip ring I can see that there's a lot of wear on the cable

maybe what I should do is just get a bunch of spools, no rod, and leave them on the floor.

and use them as hand tools to make it easier to coil by hand.

[astral lily]

Personally - I use hooks and hand-wind my cables. Everything from 6ft USB cables to my 125ft power extension cord

[random cypress]

(I just don't like hand coiling)

I think I'd rather roll a wheel than try to wrap a cable in a circle

[astral lily]

I didn't used to, but after practicing and doing it daily for a few weeks, I started doing it with everything

Not saying you have to - just a thought (and my personal management preference)

[random cypress]

yeah, I wonder if I could get that comfortable with it

do you have some kind of fastener to hold the coil together when you're done?

[pine igloo]

hand coiling as doing it with your finger or with a hand wire wrapping tool like jonard ones?

[random cypress]

I was using it to mean turning a straight cable into a coiled cable with no tools

[astral lily]

This is the technique I use.

took me about a month to master it but now I can wind a 25-ft cable in about 15 seconds (never timed it, but maybe I should

https://youtube.com/watch?v=kda4DPAn3C4&t=55s

[random cypress]

lmao "overworked and underpaid"

[astral lily]

Usually Velcro

[random cypress]

yeah, that's what I use too

@nis pointed out a while ago that the over/under method in that video doesn't keep the turns parallel, but that's probably fine for me

[astral lily]

or the generic "hook and loop" fasteners, don't know if I own any Velcro-brand stuff

[random cypress]

I think what I'll do is somehow get my hands on a single spool and try out hand-coiling versus using the spool as an aid.

[astral lily]

It's true, but when I'm storing cables, my goal isn't parallel, it's quick deployment when I need it next, and cable longevity

[random cypress]

thanks for your advice, you probably saved me a lot of time!

[random cypress]

tbh I don't really know what parallel even does. is it something about inductance if you plug in the cable while it's coiled?

[astral lily]

I'm sure you could rig something up if you wanted a DIY retraction, like a string with a weight on one end or something

[astral lily]

I think most frequencies that would matter don't make much difference if it's parallel.

Parallel could look cleaner aesthetically.

But if you're wrapping in a circle, truly parallel or just "vaguely the same size of circle in the same direction, you're not rejecting and EMI like 60Hz hum. If you want rejection, you'll need to wrap it figure-8 style. (That's generally how pros will wrap an analog audio snake if there's excess while in-use.)

[mental mica]

I spliced into my car’s overhead 12V, added a 5V buck converter, and used it to power a dashcam!

[pine igloo]

I'm a bit confused by firmware/bootloader/sketch

[icy moth]

What do you mean?

Like the difference between the three?

[pine igloo]

seems to be 3 separate things, but I can only do a sketch on an arduino ?

and if I changed my bootloader I'd potentially brick it ?

[icy moth]

Okay so firmware and sketch are essentially the same thing

[pine igloo]

and there is a sort of firmware as some sort of "BIOS"

[icy moth]

A bootloader on the other hand is a section of memory that handles startup, peripheral configuration and test, and whatnot

Usually you don’t change the bootloader unless it’s corrupt or you want a different base state

But firmware is essentially the code you design to run on a system that you use to enable/disable peripheral like i2c, SPI, can buses, configure other general purpose GPIO, set system interrupt event handlers, etc..

Arduino sketches is just a more specific term for firmware on Arduino devices

[pine igloo]

I answered a question before and they set their board put a led on high, and I said to save its state to ram and someone else said that the sketch could only run after what they were describing. Was it their bootloader that did that then ? If the software couldn't avoid this issue ?

[icy moth]

Right, a sketch or firmware runs after the bootloader runs

Bootloader are stored in what’s called bootrom

[pine igloo]

could you possibly tell a bootloader to permanently load a specific sketch even after powering down the device and back up ? a default one if there isn't any^

I got a new board that had a default sketch but it's gone permanently after I uploaded a new one so the default testsuite menu is gone forever

[astral lily]

Not really because the available storage size for the bootloader is minuscule compared to the available storage size for the sketch.
It's conceivable, but probably not practical, that you could have something equivalent to a handful of lines of code that would execute within the bootloader space if it checks and sees the sketch area is empty

[pine igloo]

ok, when I look at the specs of a board how do I know how much space it has for a bootloader ? For instance for an esp32-s2 I seem to have to dig deep into the manuals for it

[icy moth]

Well, usually we don’t worry on ESP32 because it’s preprogrammed

[pine igloo]

Intresting esp32-s2 seems to have that capability to load a test firmware in production by modifying their open-source bootloader

[icy moth]

It’s not like an AVR/SAMX product that need a bootloader “burned” before it’s programmable

[pine igloo]

https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/api-guides/bootloader.html

[icy moth]

Yeah, you can do that with microchip devices too

[pine igloo]

corollary general question as well, how do I compare 2 MCU from complete different companies ?

I'd like to a few cheap boards with various architecture so I'm not blocked on new projects by chips shortage etc

[icy moth]

Usually people compare RAM, Flash, peripherals, configurability, etc..

Available pins, buses, and how pins can be configured

[pine igloo]

but stuff like TI/STM are completely unfamiliar to me and I don't know to compare say a STM F3 or TI CC3320 to rp2040/esp32-s2/esp8266/uno/teensy 4.1/grand central m4 that I already know a bit

[icy moth]

Well, look at the data sheets and narrow down by suggested applications first

Usually ones with similar intended applications have similar specs.

TI MCU products for instance are typically intended for low power mix signal applications

Usually having decent DAC and ADCs on board

[pine igloo]

I guess I have an hard-time translating physical need to electronics specs

As a wonder if some boards are better at handling collision/vibration (being in a 30mph r/c car for instances) or if that is something you have to provide with the enclosure

[icy moth]

Usually there are ones specified for automotive design

TI makes some for that applications

But a lot of that comes to mechanical design considerations if you can use or find automotive grade parts

[pine igloo]

I mean I supposed very small ones like pi pico rp 2040 would work since smalller surface area and smaller mass usually mean less affected by force

[icy moth]

I wouldn’t say size is much if a consideration rather than solder quality, enclosure design for mitigation of vibrations and shock

Things like crystals are very susceptible to shock and it can either damage or skew the precision of the crystal if it’s bad enough

[pine igloo]

I guess I'll take a look at this. My current annoyance is that cheap small boards all seems to be 3.3V. Not many are 5V. Why?

[icy moth]

Lower voltage = faster clock speeds

So 5V has speed limitation as it gets hotter faster as faster clock speeds increases current consumption

Lower voltages mean we can get much faster speeds. Which is why you’ll see newer RAM and CPUs having core voltages around 0.9-1.2V

And when you overclock a computer, you’re adjusting core voltages

[pine igloo]

AH ah! That is why they have those 100mhz speed while my ryzen is over 2.6ghz...

by my ryzen is 1.3V or so

couldn't even power a led

[icy moth]

The good news is most CPU have 2.5V and 3.3V supplies to handle 3.3V IO

[pine igloo]

bah I seem to have a knack for always picking the wrong MCU for the job. And when I pick "right" there are tons of gotcha I would only have found out by reading(and having the time to do so) the manuals of 20-30 MCUs. Esp 8266 is a good example of what I mean

[icy moth]

There are plenty of great general purpose MCUs

SAM E/D 5x are great

Plenty of STM32 are great too

[soft rune]

hi

can someone help me with an electronics question, pretty basic stuff

[icy moth]

Best thing to do is ask your question and someone will help ya 🙂

We’re very welcoming here so no need to ask permission 🙂

[pine igloo]

I wonder how to ask a question about electronics IRL when I know they will approach the problem from the other end that I want to approach it and I already know their end won't meet my specs

[icy moth]

There are generally two schools of thought for engineering design, too down, and bottom up

Top down takes a highly specific product and seeks to break it down from the top in increasing complexity

Bottom up seeks to take an abstract idea and define a more broad idea in more specific terms

[pine igloo]

case in point: my r/c smart truck. I already know this:

I've been researching these different types of motors/angles and I doubt they can be bridged by now. The one that seems to answer my issue most is the R/C angle but I know makerspaces are former/active engineers/teacher types so they are going to go for the it's basicallty a custom small car angle and want to put recycled brushed motors on it

[icy moth]

So yours is a top down approach

[pine igloo]

Not sure, I mean if I can't figure the structure and motors it's not really worth starting for me

[icy moth]

You know the specifics of what you want so you are designing around those specifics

[pine igloo]

Trying to meet specs but electronics hobbyist motors can't seem to answer them unless I go with 2000$ per motor stuff from the like of honeywell or General electric or that german company I forgot that start with an F

R/C have been doing it for 30 years and seems to have exactly the power I need but are extremely proprietary. Just found a full spec document and it's not even PWM but PWM arrays under a deep layer of a custom protocol

Meanwhile someone broke with a junkyard would probably just get a 240RPM electric scooter bike 24/48V motor but these will be expensive in structural materials/etc and need dangerous acid batteries...

Maybe I should just tell them my design need 4x240W motors or one above 1100W and see what they come out with ?

really don't want to end up with a 800 feet per hour snail miniature rover like this NASA JPL one: https://opensourcerover.jpl.nasa.gov/#!/home

The other difficulty I have with them if that they seem to think I shouldn't attempt such a complex and expensive project at the moment. But it's a life goal for me and something I dreamed of for a long time. All the other smaller/easy projects are "nice to have for me" but this one is much more important for me.

What should I do ?

[icy moth]

How big is this intended to be?

[pine igloo]

1 to 1.5 cubic foot. Should be enough for the two technologies I really wanted to experiment with in my lifetime 15 years ago: LIDAR and FLIR and a pi to be able to use them

would only be slightly longer than a cube (so something like 1.25 feet long, 0.8 feet large 0.9 feet high)

My plan so far is to start from a r/c truck and use everything except the chassis/gear system

Would like to use it outside during light rain, so so far it would be a weatherproof enclosure mounted on an extruded aluminium channels cage

Already got 2 ToF sensors for it, when the motors are settled I'll be able to design the construction in solidworks as I have the .STEP file for the enclosure and the channels

Makerspace is closed all summer so it's the last time I have to get the makerspace input before I start

[icy moth]

Gotcha. Seems reasonable to do with most COTS RC motors and whatnot

[pine igloo]

Of course I won't buy anything before I'm certain it can roll from a remote control transmitter safely and it's properly fritzed

It's just that when I'm certain for the motors I can finally take care of the next issue: gearing and temperatures

second option would be to get a slower r/c truck and all the smartiness would be in a towed trailer

would need to be slower to force-stop the main vehicle (proximity sensors instead of lidar, with an offset for the front of the main vehicle)

That way I wouldn't lose any warranty altering the chassis and since the trailer is unpowered it would be much simpler (and no complicated gear system)

[pine igloo]

Hi 👋 I’m new here and new to electronics in general. I recently designed my first simple PCB with KiCad and got hooked. Now I’m inclined to get more hands on experience doing a custom design based on the RP2040. I was looking at some of the Adafruit repositories as a learning resource but couldn’t figure out the BOM of these designs.

Specifically I was looking at https://github.com/adafruit/Adafruit-KB2040-PCB and https://github.com/adafruit/Adafruit-MacroPad-RP2040-PCB

To validate my choice of Crystal and capacitors against what others are doing.

In the schematics and BOM I only see generic parts and the symbol for Y1 does not really match the footprint.

Am I missing something?

Are the actual parts include in these repos?

[pine igloo]

https://blog.adafruit.com/2022/02/07/500-adafruit-projects-have-been-certified-as-open-source-by-oshwa/

Reading this, really sounds awesome 😺

I didn’t see any links to specific boards in that blog post. Is there a list of Adafruit designs that embrace the spirit of the Open Source Hardware definition somewhere?

Or is Adafruit committed to follow the Open Source Hardware definition for all hardware designs?

[icy moth]

They work to make as many of their designs open source as possible

As for BOM, you can extract part numbers from the schematic

[pine igloo]

I really like there is fritzing for a lot of adafruit stuff and 3d cad files

I might have to start making parts in fritzing 😦

can't find PFC8574 which is fairly common as an I2C extender...

@icy moth have you successfully done so?

[hearty karma]

Should be buildable

[pine igloo]

😦 😢

[pine igloo]

Person on bike going to interfere with lidar and going to be laser bombarded though...

[hearty karma]

I'm not sure I agree. I can think of mounting solutions that would avoid interference, LIDAR doesn't have to be laser based, and low-energy laser beams are harmless anyway.

[icy moth]

Just open the schematic and brd files in KiCAD

[pine igloo]

I mean the rider is physically in the way for a 360o system

[icy moth]

You can import them directly into KiCAD which is super nice

[pine igloo]

unless you mount it on the top of their head

with a long wire that could get entangled in the wheel, chain etc...

That’s what I see with Atrium Viewer

I’ll try with KiCad

Just to be sure

[hearty karma]

If I go to DigiKey and enter 535-9857-1-ND it brings up the actual part, which is an Abracon ABLS2-4.000MHZ-D4Y-T, along with the datasheet and specs.

[icy moth]

Adafruit sometimes uses a generic part that shares a foot print

[pine igloo]

digikey interface confuse me so much

[icy moth]

I do the same

[pine igloo]

Like if I try to find an STM F41 there iss like 40 models and none of the MCU links to their dev board etc...

[icy moth]

Easier than having 30 different crystals to pick from if I’m just choosing based on size

[hearty karma]

Doesn't have to be 360° and even if so, this is easily addressed with multiple sensors. I've routed wires on bikes in a variety of ways to avoid moving parts, it's not hard.

[pine igloo]

I thought of something like this once but I think it would take a lot of power to prevent me from going in a particular direction with the front fork or activating the brake

and would be easy to steal as well

The only big thing that seems realist to me as an hoverboard, compact enough so it won't be stolen since can be put in a backpack

and with the vibrations/shocks not sure ToF sensors would hold for very long

[icy moth]

I found this part with the Digi-Key mobile app. https://www.digikey.com/en/products/detail/ABLS2-12.000MHZ-D4Y-T/2001236

12MHz crystal pulled from that screenshot

[pine igloo]

Also I thought about it last night and there is no way I'm spending 1000$ on an r/c / robot truck project when bikes are 6k$ and fuel scooter are 2-3k$...

and high-end 250g drones are 900$...

[icy moth]

I’m planning on making an electric go kart now that I have the space to build

Just need to get a welder and some tools for working structural aluminum tubing

[pine igloo]

I might still get a 200$ rc but that is for the indoors 1/16 to 1/24 rc. Added bonus if I can actually drive the motors

[pine igloo]

I mean that’s my point, it’s a generic symbol

The specs for spektrum stuff is nice and all but the kit alone (batteries/1 motor/1 esc) comes to about 800$ which is insane...

It’s not the part that’s used

[icy moth]

Sure

Part of the schematic capture is picking the parts based on the data sheet

That specific crystal is suggested by the Raspberry Pi hardware design guide for the RP2040

[pine igloo]

Either I’m doing something wrong or this are not the sources for the actual board

I would just like to understand what exactly I’m doing wrong?

[icy moth]

Likely nothing at this point.

[pine igloo]

Before making unfounded allegations that is

Because as I understand it this is not in line of the open source hardware definition

Also, the git commit history looks very fishy

[icy moth]

But the schematic view is just that, gives you. A view of the circuit specifications

[pine igloo]

Again, I don’t think it satisfies the open source hardware definition

You don’t have any obligation to follow that definition, but claiming to do so and not doing it is, well, lying

[icy moth]

If it’s oshw certified then it does

It’s very rigid

[pine igloo]

Well that’s exactly what I’m puzzled about

[pine igloo]

Problem with gas scooter/bike or golf cart is I don't have parking space 😄

[icy moth]

I personally wouldn’t read too far into it. Sometimes things seem off but that doesn’t mean they are. Open source allows you to see designs openly, but it doesn’t guarantee complete part parity

Especially because overtime parts might be made obsolete or discontinued, but that doesn’t make the design less open and accessible

[pine igloo]

is there something adafruit that looks a bit like this? kinda stuck since I cant fritz it :(

[icy moth]

Open source is built on the premise that it gives to source full public view that can in many circumstances, altered by the end user for purposes that were not originally intended

[icy moth]

What is it?

[pine igloo]

Well that is exactly what I’m trying to do

[icy moth]

I used Adafruits designs as a reference, but I always seek out parts that work for my situation and skill level

[pine igloo]

I’m still not sure, are the parts there or are they missing?

[pine igloo]

PFC8574 I2C backpack for LCD1604

since this along with the LCD uses many wires it really ruin my schematic if I can't fritz it

so my plan is to hopefully start from something similar that has a fritzing part and change the connections. But I don't know the adafruit (sparkfun has a big fritzing library as well) gear well

fritzing has a pfc8574 but it's an unrelated chip without breakout

having the correct pins is much more important than the looks (different color is fine but not completely different shape)

[icy moth]

I wonder if someone has made a frotzing file for it

[pine igloo]

I looked for it but all I could find is peoples having unrelated circuit using the LCD but not the backpack

hum nvm I guess I didn't look hard enough 😦

[icy moth]

Here’s my advice:

I suggested pulling parts because usually they are available from the schematic but not always. Part of designing hardware is searching for parts based on your needs. So you would look up for instance a 12MHz crystal with 18pF load capacitance. And you’d pick a crystal that was like that.

The same can be applied to all parts

[pine igloo]

also I cannot name even one vendor who went open source hardware prior to Adafruit. ;)

afaic they lead the way. Period. ;)

I assumed most of the search results were the unrealted IC but I just had to add "expander" to the google search

@pine igloo Have you actually verified this yourself?

[icy moth]

If not, if you can find the board schematics and whatnot, you can creat fritzing objects through a very roundabout way

well, Adafruit started in before the major housing crash of 08

[pine igloo]

https://www.oshwa.org/definition/

you're new. welcome. I'm not going down this avenue of pursuit any further. I think I've made it clear how I feel. ;)

bah it's not the correct one, it's lacking pins

normally it should hav as much pins as the lcd on the top part

also mine has the 4 left pins on the right side

[icy moth]

All I can say if you have questions about schematics or whatnot that you don’t feel are being answered well here, or you don’t trust the good faith of those who regularly reference Adafruit designs, you’re free to email Adafruit support and ask questions or ask during Desk of Ladyada on sundays

[pine igloo]

@pine igloo Well first of all thanks for your reply. Of course I respect your feelings, and you are free to feel whatever way you want. But that is not my question. What I am trying to understand is, am I doing something wrong or is Adafruit releasing incomplete design files.

I don’t want to be annoying, but I think that is a legitimate question

Rather than jumping to conclusions I would rather first want to understand the picture.

I think skerr is the exact person to be talking to, and that they already confirmed you'd doing nothing wrong (you have the available information 'already'). That's how it looks to me.

[icy moth]

Some parts are left generic from my understanding, mostly because the part they use might not always be available

[pine igloo]

You cannot just use an arbitrary crystal without specific resistor capacitor set up

[icy moth]

As for common parts like capacitors, resistors, crystals, it’s kind of pointless to put exact part numbers because there are sooooo many available

Adafruits design follows the RPi hardware reference design

[pine igloo]

They’re not using the same crystal as the basic example

[icy moth]

They offer a suggestion but don’t constrain you to that specific crystal

[pine igloo]

They are also not using the same Crystal as the pico pi

I'm a bit puzzled why you guys mention rpi and open-source in the same sentence

rpi is still completely closed/proprietary afaik ?

That was the big difference with arduino ?

;)

The RP2040 is somewhat well documented. I think it was received quite well by the usual vendors (Adafruit, Pimoroni, SparkFun &c.)

They all came out with boards for that chip.

to take the logic further, if they offer a hardware reference design while still being closed-source/proprietary I'd expect that to just be a a suggestion but lacking enough details/specifics so that someone could just copy them and take their market ?

At least I didn’t mean to make any statement about the raspberry pi foundation 🤷‍♂️

and hence resellers like adafruit would respect that restriction? (trade secrets)

All I want are the schematics. That's big.

so if there was any crystal in such a "suggested" design for an rpi I'd take it with a grain of salt and just a suggestion

because they are obviously not going to give out enough to have their business stolen ?

[icy moth]

The thing is open source doesn’t always mean you’ll know all the exact parts they use, if you want to know the exact part, email Adafruit or ask during ask an engineer

I use this crystal on my rp2040 design

I found this part with the Digi-Key mobile app. https://www.digikey.com/en/products/detail/ECS-120-18-33-AGN-TR/9648931

It’s not in the specification but it works with the design well and it’s one I could get

[pine igloo]

I understand kbdev point thought for crystal it's not like a resistor where you can sorta replace it by mounting others resistors in series/parallel

since crystal are physical things that are custom grown

@icy moth with 27nF + 100k I guess?

[icy moth]

27pF + 953ohm

Series resistance should be around 1050ohm so that’s as close as I could get

[pine igloo]

1k I meant

Close enough

i mean for superconductivity crystal you just can't take a replacement, has to be the exact correct chemical structure and angles internally and a femtometric tolerance. I assume crystals for electronics are the same and you can't really have a big tolerance/same with lens ?

[icy moth]

Some people have omitted the crystal drive resistor for their designs and those work too

[delicate quarry]

Trying to match a product part for part is especially tough these days due to the component shortages plaguing the industry, so I wouldn’t be surprised if there were minor variations in actual part sources. Plenty of boards have had to substitute components due to sourcing issues IIRC…

[pine igloo]

To play devil advocate thought it's mostly a shortage for inexpensive parts

[icy moth]

And lots of microcontrollers..

[pine igloo]

Almost everything related to PIC/PLC seems to be really stocked well as well as high-end 1000$ boards or high-end 300$ motors...

[pine igloo]

Maybe now yes, as the GPU situation relaxed

[icy moth]

PIC didn’t face the same shortage issues from what I saw

[pine igloo]

Like if I want a GE or honeywell brushless motor there are tons of them in stocks..

[hearty karma]

While jellybean parts (resistors, capacitors) are often going out of stock, they're easily replaced with equivalents. Some more specific parts (such as microcontrollers) aren't so easily swapped out. Personally, I consider crystals to be interchangeable parts.

[icy moth]

But samd/e devices from microchip? Still long lead times

[pine igloo]

My makerspace will even drive that get recycled electronics because of the shortage and offer bounty for some of them...

[hearty karma]

Huh, I should see if there's somewhere around here looking to recycle electronics. I seem to have accumulated a backlog...

[pine igloo]

Unless convinced otherwise, I still maintain that the released files are not in line with the Open Source Hardware definition.

[pine igloo]

for a google search nearby, they might use the word "upcycle"

the 2nd makerspace in my city are often looking for almost any used stuff to upcycle in projects/electronic projects

[delicate quarry]

Inexpensive is relative. I prefer to think of it as parts with silicon semiconductor dependence

[hearty karma]

Makerspaces are thin on the ground around here. The most local one folded years ago, the next most local one doesn't have anything like that, and the next most local is a 45 minute drive each way.

[delicate quarry]

Freaking Xilinx fpgas and their 70+ week lead times…

[hearty karma]

That's why I went with LemonRX. 3 ESCs for $40 is a lot more cost effective.

[hearty karma]

And closed source toolchain

[icy moth]

Feel free to contact OSHW to discuss their definitions of open source and how probably a majority of certified products don’t meet what you expect them to be.

Not to be cynical but it’s kind of a nitpick

[main hemlock]

@pine igloo Adafruit similar thing is https://www.adafruit.com/product/292, but it's not PCF8574

I'm not sure what your q is

[pine igloo]

my question is that I have to fritz it and I can't find a fritzable part that kinda looks like it and has the correct pins

[hearty karma]

I have more of a beef with large commercial companies that use open source software (such as Eclipse or gcc) to build closed source software in violation of the license, than small companies that release open source hardware with a few missing details. If I'm re-using a design, I expect to have to do some engineering to re-create a manufacturable version.

[pine igloo]

If I can't fritz it I can't communicate well to other what I'm trying to do

[pine igloo]

and peoples who put .exe on github without any source 😄

Wish there was a way to report it, for me it's more bad than DMCA issues...

I may not necessarily agree. I think there is an agreement between the OSI and and OSHWA regarding trademark use. And as I understand it part of that agreement is what a user can expect from open source hardware.

github isn't an ftp site it's a source code hosting site...

especially when companies do it

[hearty karma]

Oh don't get me started on DMCA, that's a giant mess.

[pine igloo]

Too controversial for here I think 😄

[icy moth]

Look, it’s never going to be perfect. To expect it to be perfect is not really reasonable. Plenty of people have derived their own designed based on open sourced designs without issue. I don’t see why it’s an issue in this case

[pine igloo]

But feel free to start in DM if you want

[main hemlock]

@pine igloo the specific case of the crystal is that we've used a couple of different crystals there, in an effort to solve some startup problems. When the schematic was drawn the exact crystal wasn't known. In general if the exact part isn't specified it's because there are several possibilities.

[icy moth]

If you don’t know what crystal to use, ask for suggestions

That’s what the community is here to do, provide help

[main hemlock]

for instance in some cases we have had to substitute other parts (e.g. different flash chips)

[pine igloo]

another thing that annoys me, "chip shortage" but the MCU has tons of stocks, while dev boards using it aren't in stock....

So if you are rich and have access to industrial PCB making it doesn't affect you because you can still get the high-end boards or the MCU itself and print a dev board for it

I see it all the time on digikey...

[delicate quarry]

The point of open source hardware is to have some means of reproducing the hardware yourself. Even if the crystal has been substituted for another, the point is that the designs are accessible as a resource for anyone who’s interested. The exact part used on the schematic may not match the product 100%, but if they’re functionally equivalent it still serves its purpose.

[icy moth]

Or the opposite with STM32 dev boards but no chips lol

[pine igloo]

@main hemlock Glad you answer. What I am puzzled about is, are the files on GitHub the files that you use for production. Or are these still stripped down version?

I also bet stuff like DHT11 will never be in shortage, they are kinda the electronic version of MTG lands 🤣

[main hemlock]

they are what we use for production. There are internal BOM lists used in the factory which specify which part, based on our own internal stocks

occasionally we get behind on publishing a board rev

[icy moth]

I saw companies were buying STM32 dev boards just to harvest chips so ST started limiting the number you could buy lol

[pine igloo]

I was in shock yesterday that pishop would let me buy 100 picos if I wanted yesterday ...

[main hemlock]

we don't strip info out of Eagle files before publishing or anything like that

[icy moth]

RPi Pico? I think there are a lot of Pico stock available so it’s probably not an issue to buy 100

[delicate quarry]

Rp2040 is in surprisingly good supply, to be fair.

Unlike the zero and 4b, there really isn’t a shortage in pico.

[pine igloo]

makes me sad when I compare pico / esp32-s2 with my uno rev 1 and rev3...

@main hemlock to be completely honest with you, the GitHub history does not look organic

Feel like comparing an IC chip that does the same thing to a giant-sized IBM electromechanic board from the 1930

[main hemlock]

there are internal repos; the design is copied to the public repo. The internal repos contain things we can't publish

[delicate quarry]

Oh yeah, 328p uses a much older production line that’s gradually being phased out in favor of the newer processes. The fact that they’re still in production at all shows how much they’re valued, though.

[icy moth]

Lol, you should see my board repos lol… definitely not looking organic

[pine igloo]

I use oregano, is that okay