#help-with-linux-sbcs

1 messages · Page 6 of 1

meager girder
#

if I get a fan for my rpi4b is it going to block my gpio ports or the possibility to use an extender on it ?

zenith crystal
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depends on what the fan is attached to - i've got a CRICKIT Hat and i just plug the fan into an unused servo +5 and GND

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and how the fan is placed (mine is kinda tie-wrapped to the end of my makeshift case)

meager girder
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I got an armored case with 2 fans for it and 3 thermal tapes. Also the problem is kinda solved because I will get an extender eventually . Atm a sparkfun qwiik pi HAT is going to sit on it using 2x20 header pins

zenith crystal
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will need either the V1 (sticks out the other way) or lots of stacking headers

meager girder
#

yeah I got a bunch of stacking headers of different sizes

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I just dont understand how the the extenders that takes 2x20 pins can even extends to 3* 2x20 pins on a pi 4

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or 2x20 pins on a pico W

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Like that doesnt seems to respect physics (but what do I know)

zenith crystal
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some boards are "thru-hole" and headers with extra long pins will stick through so that you can put another header/hat on top of that

meager girder
#

seems like it`s thru-hole and it hooks to the I2C pins

zenith crystal
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nope, not thru hole (I have one) - the CRICKIT Hat Is for sure (looking right at mine)

meager girder
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my next batch is going to be to get some cameras and solution for power (ie: step-up and supply constant 3.3V or 5V no matter the battery)

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ok 😦

#

so I cant put another HAT on top ?

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or I could if I put the expansion board then the sparkfun one on top ?

zenith crystal
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if the pins line up i think it would work

meager girder
#

"Simply plug the replicator board into your Pi and plug any additional circuits or breakout boards into additional heade" I suppose the sparkfun is some sort of breakout board at the basic level

zenith crystal
#

yeah, it's just breaking out the headers into a "super bus" kind of thing - there's a couple of similar things from Pimoroni - but you still have to worry about stuff bumping into each other 😁

meager girder
#

I got this case along with the recommended super long 2x20 addon product ie: "If you plan on connecting a cable to the GPIO connector, you might need a GPIO Stacking Header for Pi - Extra-long 2x20 Pins"

case.jpg
zenith crystal
#

that still looks like it's going to block a couple of pins, so at least one of your extender strips won't take a hat

meager girder
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good the know I'll ask about it on my next order. Was mostly getting a case and many enablers from adafruit in this order

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and 2x pico W

zenith crystal
meager girder
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Ill keep that in mind. Checking mouser/digikey because I need at least 1 sparkfun qwiik mux as well and pishop doesnt have a couple of things (and that stackin header)

modern tundra
#

does anyone here have knowledge on gstreamer pipelines

wheat leaf
#

hi, i'm want to use my rplidar A1M8 with a raspberry pi3, in first time i try to use the roboticia library but it doesn't work ( "descriptor length mismatch"), so i want now to use adafruit but i don't know what shoud I download on my raspberry to make it working. ( I can't use internet on my pi 3 B. Thanks for your help and have a good day !

broken shuttle
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I've done it before, so I might be able to help.

modern tundra
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I have 3 cameras that broadcast via udpsrc that need to be stitched together

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Apperently it is possible with gstreamer

broken shuttle
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I'd have to deep dive into the documentation again, but it depends on what you mean by 'stitch together'.

zenith crystal
modern tundra
broken shuttle
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Yeah, I'm asking how you want them stitched. Are you wanting them side by side?

crystal yew
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does anyone know where i can find current documentation for the Thermal printer lib that is not no longer maintained or supported? i have a thermal printer guts but with the new adafruit-circuitpython-thermal-printer lib from pip3 does not support changing of the heat_time setting or putting the printer to sleep like the old lib used to be able to do

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both have a similar message This library is archived and no longer supported

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i'm a bit stuck on what i should be using if both are not supported and there is no replacements provided

faint sparrow
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Does anyone have any suggestions for a SBC that is as flat as possible (while still having IO, no CM), fast, can run fine off 900mA over USB C, and can be configured as a USB ethernet gadget through its primary USB C port? A Pi 4 can do this, just not that flat

fickle rose
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So a SBC that’s as flat as reasonably possible, fast, uses less than 1A in normal operation, and has usb-otg over the power usb-c port so a rpi 0 2 W alternative with usb-c

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The radxa zero or radxa zero 2 might be what you are looking for

earnest roost
# crystal yew does anyone know where i can find current documentation for the Thermal printer ...

The "new" lib is specific to CircuitPython which runs on microcontrollers. You might be able to run it on Raspberry Pi using the Blinka library. The "old" library is standard Python 3, mostly written for Raspberry Pi. Given that they are archived, you probably need to fork the repository and investigate the code to see how they work. You can find an Learn Guide at https://learn.adafruit.com/mini-thermal-receipt-printer/circuitpython.

faint sparrow
fickle rose
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Inflated?

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What do you need a flat SBC for?

faint sparrow
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ipad attachment

agile depot
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Hey so I have an ODROID-H2 computer I'm trying to connect a 2.5" HDD to via the SATA port, but whenever I start the machine up after plugging everything in it doesn't detect the HDD and the screen starts freaking out whenever I move the mouse. I'm running the latest Ubuntu on it.

broken shuttle
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How are you powering the drive?

agile depot
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Im using the on-board drive power supply

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I think the drive is pulling too much power, but I measured the current and it was around 600mA-1A

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My multimeter is dying though, so I wouldn't really trust it

meager girder
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Having a bit of an issue with a case with sticker thermal pads. Right is what it's supposed to looks like. Mine apparently had only an opaque sticker on the case side and the IC side has no clear protector to take off even tried to peel something very carefully with my dentists tools. Any idea ? Is it a valid reason to take off a star in the review because the one they shipped seems really bad and decompose on its own with a slight touch ?

4343.png
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Asking in here because this is for the pi4b and your answer might be to get something else if it really really matter

turbid rivet
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Yeah, that sounds like they took a fine case and supplied terrible pads to go with it. If the case is nice enough, could be worth just getting pads instead of a whole new case.

meager girder
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It's nice but the fans dont seems to start. I get the red led that keeps being on and the green one flash once in a while. It says to connect it this way on the pinouts specs that seems to be 5V(red)/GND(black)

pi_issue2.png
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Is that one of these new fans things where they only start when necessary or something ?

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instructions here dont mention needing any software/driver: https://www.pishop.ca/product/armor-case-with-dual-fan-for-raspberry-pi-4-model-b-black/

PiShop.ca
Armor Case with Dual Fan for Raspberry Pi 4 Model B - Black

Canadian source for Raspberry Pi, Arduino, Micro:bit, DIY electronics, robotics, and educational products. Raspberry Pi approved distributor for schools, commercial and personal projects. Microbit accessories and educational kits. Huge collection of Adafruit and SparkFun products in stock.

zenith crystal
#

probably - run sudo raspi-config and select "Performance Options", then "Fan"

meager girder
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I already did with the preferences in the gui interface but that wont do anything normally because the fans dont have a control wire

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so they should always be on and turn on as soon as power is on

zenith crystal
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yeah i have a case + daugherboard type thing that includes the fan, so it's probably a bit different

meager girder
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I guess Ill email pishop and asks them nicely to send another pair....

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kinda weird fans without pwm...

zenith crystal
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yeah, it does look like they should be on all the time based on the product page

meager girder
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Implied but yeah I checked with a multimeter and says 4.9xishV between the two pins

primal sleet
#

Can anyone help do a manual install of linux on a second drive i have ?

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wanna dual boot with windows

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but dont wanna do it on the main C drive

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the 2nd drive has data that i dont wanna lose either

zenith crystal
# primal sleet the 2nd drive has data that i dont wanna lose either

first i would use a "live boot" of Linux and re-partition the seond drive (e.g. shrink your existing partition) and leave the rest empty

i would google for "dual install" and just indicate during the disk setup that you want a manual disk install - you should be able to select and target that empty partition for the installation

the reason i recommend actually searching for the dual iintall is there are probably more up to date instructions on line than are in my head 😏

umbral sable
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And for goodness sake, back up the data first...

zenith crystal
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🤣 man, i do tha so automatically i don't even think about it...

primal sleet
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all other important docs are always backed up

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and thanks i fighured this out. I unallocated 50 gigs of space from my hard drive and then just made home, root, swap etc dir in the ubuntu installer

meager girder
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fans were upside down that's why it didn't work FML

pi_issue2.png
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How did the fans even know anyway 🤣

humble marsh
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i don't understand: was the connector reversed?

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maybe there's a diode

meager girder
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no like the label should not be visible

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the connections are fine but the label side had to face down

broken shuttle
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Like I said before, those fans will have a driver IC in order to run the brushless motor. That IC will behave like a diode if the polarity is reversed.

meager girder
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but the polarity isnt reversed, it's just the side along the x axis in 3d space

broken shuttle
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So... they were rubbing against something?

meager girder
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😦

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I dont like it when I think Im explaining something correctly and nobody understand

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Label face down and now they work. Exactly same pins as before

fwee.jpg
broken shuttle
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... so yeah the "hubs" were probably pressed up against something and that prevented them from turning.

meager girder
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I installed the long pins extender too since the picture above but that doesn't change anything for the fan

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decided to ask them about the lack of stickers label on both sides like the instructions. The sticker on the chip side isnt very sticky...

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temperature panel in x-window is saying 34o but I dont know if it's farenheit or celcius vs 47o without the fans yesterday

zenith crystal
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C - that's a cold CPU, too - i regularly get my Pi 3 and 4's into the 65+C range

meager girder
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that is the cpu temp the system temp is 2-3o below

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without a heatsink/fans it would be like 56o after a few hours but I have an climate controlled room at 72oF

zenith crystal
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these will keep it quite happy then

meager girder
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any way to get those temps in the console with the unit of measure shown and if it's relative or absolute ?

zenith crystal
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not off the top of my head - but all the temperatures should be in C and absolute

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dang - that was easy /usr/bin/vcgencmd measure_temp

meager girder
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my Pi dont seem to be enjoying me using it at 4K on a 4K screen 🤣

zenith crystal
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there's some video driver tweaks that you can do that will make it "better"

meager girder
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like kinda laggy when im typing and when moving the cursor in the discord web client

broken shuttle
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No surprises there.

meager girder
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what do you mean ?

broken shuttle
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I'm not surprised that a raspberry pi is struggling to run a full desktop environment plus a browser running discord at 4k.

lilac lagoon
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not really an sbc question but im a noob when it comes to linux, is there anyway to prevent linux from just creating a bunch of folders when i plug in an empty usb drive?

broken shuttle
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Uhh... it shouldn't be. What's it creating?

ornate glacier
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My printer's control Pi has stoped working after an update. I have validated the filesystem is not corrupted, but the act light never activates. Is it possible to do some Linux magic and make the SD card boot again, or should I just re-flash (honestly, I want the first option more as a question of "can I" and less of a "should I")

broken shuttle
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The answer to "can I" is almost always yes.

ornate glacier
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Ok, then "how can I"?

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I am not super familiar with the NOOBS boot partition scheme, but as best I can tell, the kernel is never loading...

broken shuttle
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I've never actually used NOOBS, I just partition and extract whatever image I want.

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You should be able to wipe the boot partition on the SD card and then copy the contents of the boot folder from a fresh image.

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(This assumes you are running a Linux distro on your PC)

ornate glacier
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Why of course I am! I will give that a shot. Thanks!

signal meadow
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Hello, my raspberry pi suddenly stopped detecting an i2c device - this device is working without problem on another rpi.
Can i2c be damaged in this case?
No configuration has been changed - it worker for a year and suddenly stopped.

broken shuttle
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What pullup resistors are you using?

signal meadow
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I am using DFROBOT SEN0251 pressure sensor so it is ready-to-work

broken shuttle
signal meadow
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looks like 10k

image.png
broken shuttle
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Hmm should be alright assuming VCC is kept at 3.3V.

signal meadow
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VCC is 5V, but they said it is ok for 3.3-5

meager girder
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sensor would work at 5V or 3.3V but afaik both logic and power must be the same. If the logic pins on rpi 4 gets 5V logic it may be damaged

broken shuttle
broken shuttle
signal meadow
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so it is possible that only i2c has been damaged and "the other" part of pi is fine?

broken shuttle
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Yes it's possible to only damage one or two IO pins.

signal meadow
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Okay, thanks!

paper flower
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Are there any reasonably-priced SBCs out there that support USB-C DisplayPort AltMode? Or failing that, a shield or IC that can transcode from SPI or DSI to DisplayPort (to feed to something like an FUSB302B)?

Not having a lot of success finding much beyond IPs for high-end FPGAs.

broken shuttle
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Well, I have good news and bad news about that...

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Good news: I work on video SERDES chips that can take video from a variety of interfaces, run the data through 10-15m of coax, and then output DP on the other side.

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Bad news: unless you're an automaker you can't buy it.

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Side note: SPI is not very good for video. Even QSPI will generally be on the slow end, and I've never encountered a SoC that can actually output video directly over SPI without CPU intervention.

paper flower
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Thanks! I was suspecting as much.

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Mainly I'm trying to figure out a good way to output to an HMD that uses USB-C DisplayPort AltMode and has basic head tracking, that can be fairly lightweight, portable, and affordable. My only reason for thinking SPI was that I'm not a VESA member, so, don't have access to the DP spec.

broken shuttle
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I am (through my work). I can give you some info and confirm/clarify. Unfortunately I can't give you the spec.

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There are older versions of it floating around in the clear online, but you didn't hear that from me.

paper flower
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Much appreciated!

meager girder
broken shuttle
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Yeah it is backwards compatible

thin pelican
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Can someone help my dumb please.

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I'm using the pi400 with a hyerpixel 4 attached via adafruits cyberdeck hat. The one line config for hyperpixel works fine for raspiOS, but I can't get Parrot to push to the screen no matter what I do.

visual magnet
thin pelican
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The legacy driver install?

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If so, yes.

smoky warren
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Does anyone have experience with BBB and circuitpython? I'm having some GPIO permission issues:
I'm trying to run rfm9x_simpletest.py and I get the following issue:

File "rfm9x_simpletest.py", line 18, in <module>
CS = digitalio.DigitalInOut(board.CE0)
File "/usr/local/lib/python3.7/dist-packages/digitalio.py", line 165, in init
self.direction = Direction.INPUT
File "/usr/local/lib/python3.7/dist-packages/digitalio.py", line 195, in direction
self._pin.init(mode=Pin.IN)
File "/usr/local/lib/python3.7/dist-packages/adafruit_blinka/microcontroller/am335x/pin.py", line 37, in init
GPIO.setup(self.id, GPIO.IN)
ValueError: Set gpio mode failed, missing file or invalid permissions.

If it helps, I'm running kernel version 4.19.94-ti-r73

Below is the rfm9x_simpletest.py code:

import board
import busio
import digitalio
import adafruit_rfm9x

# Define radio parameters.
RADIO_FREQ_MHZ = 433.0  # Frequency of the radio in Mhz. Must match your

CS = digitalio.DigitalInOut(board.CE0)
RESET = digitalio.DigitalInOut(board.P9_23)

LED = digitalio.DigitalInOut(board.P8_19)
LED.direction = digitalio.Direction.OUTPUT

spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)

print("Initializing")
# Initialze RFM radio
rfm9x = adafruit_rfm9x.RFM9x(spi, CS, RESET, RADIO_FREQ_MHZ)
print('RFM9x: Detected', 0, 0, 1)

rfm9x.tx_power = 23

rfm9x.send(bytes("Hello world!\r\n", "utf-8"))
print("Sent Hello World message!")

print("Waiting for packets...")

while True:
    packet = rfm9x.receive()
    if packet is None:
        # Packet has not been received
        LED.value = False
        print("Received nothing! Listening again...")
    else:
        LED.value = True
        print("Received (raw bytes): {0}".format(packet))
        packet_text = str(packet, "ascii")
        print("Received (ASCII): {0}".format(packet_text))
        rssi = rfm9x.last_rssi
        print("Received signal strength: {0} dB".format(rssi))
zenith crystal
#

Set gpio mode failed, missing file or invalid permissions. - this sounds like your user does not have access to the GPIO bus/device

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e.g. have you added your user to the appropriate user groups? ```spi:x:999:ed
i2c:x:998:ed
gpio:x:997:ed

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wait - kernel 4????

smoky warren
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That's odd because I can use the pins with a C program (Derek Molloy's SPI test scripts)

zenith crystal
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what type of computer/controller is this running on?

smoky warren
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BBB

zenith crystal
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oh, sorry - for some reason i thought it was a Pi - nevermind 😀

visual magnet
wraith grove
#

RPis have eaten at least two of my SD cards, should I throw my raspberry pi OSes into read only mode to avoid some of that?

short cloud
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Check your power. Undervoltage will corrupt SD cards.

wraith grove
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last one showed up after the power went out, been running recovery on that one for about 8 days now

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not sure if that was originally bitrot though

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errors are scattered over a 6GB area, got it down to about 40 blocks (which honestly aren't in the way of getting what I needed to set up a new pi os on another card)

craggy junco
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Is it possible to have the adafruit MCP2221/FT232H work with gpiod libraries instead of the blinka circuitpython libraries?

humble marsh
broken shuttle
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That's... not entirely true. If the Linux kernel supports them, the kernel modules are installed, and you add the appropriate device tree overlay you actually can interface with I2C GPIO chips.

humble marsh
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@craggy junco in any case, using blinka works well and would be the easiest

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or you could see what blinka is doing at the lower level and do it yourself that way

craggy junco
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I have code that works with gpiod on most other sbcs, I was hoping to reuse this code on systems without gpio present (using MCP2221/FT232H as a replacement). It presents a lot more work to rewrite all the gpio interface code so it uses blinka instead. Thanks for the information regarding it being added to the kernel, I might just wait and see how it works out.

At present the MCP2221 partially works, I can use gpiod to set pins and get from pins, but I am unable to monitor them for changes. The FT232H does not work with gpiod at all, I think the driver for it is reserving all the pins for it so blinka is the only way to interact with it?

steady rose
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not the only way. just a different way. and gpiod would be yet another way.

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what probably wont' work, which sounds like the case here, is mixing gpiod code with blinka code.

humble marsh
broken shuttle
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You would want to do the opposite actually.

reef spoke
#

Hey folks, any suggestions for a 10 inch display with hdmi for a cyberdeck project?

broken shuttle
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Hmm check for 3d printer displays

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Lilliput makes some very fancy (and expensive) 10in displays.

dreamy abyss
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meager girder
#

How do I find out exactly how many VCC ma I have for using the pins on a rpi4b ?

#

someone told me I had a 3.5ma fan and it could take 10ma to start it and I might not have enough m/a left for it. Which is a bit surprising considering the 3A usb-c connector for a pi and I just have a keyboard/mouse/wifi connected t the usbs and that shouldn't take all the leftovers mA and leave me nothing to run things... right ?

fast bane
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same deal as we already discussed before on mcus. Its a few mA for an IO pin, a few hundred mA for the power supply pins

rotund pivot
meager girder
fast bane
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then you have to math that yourself, the pi 4 is generally about 2A give or take but that fluctuates hugely based on if it is in sleep or not. How much your peripherals use depends on which peripherals, a cheap basic keyboard is often under 50mA but one with enough RGB to light up your room can hit an amp on its own

wraith grove
# wraith grove not sure if that was originally bitrot though

and now I have one that seems to be write-locked, but not obviously throwing errors when written to?
I've tried to dump octoprint onto it several times, and zero it out once, still boots the previous install after all that (overtly different from what I am trying to put on it)

turbid rivet
#

Does anyone have any experience with the Ox64? I’m considering the viability of creating a portable serial terminal with it and was wondering how much work people have done with it…

solemn finch
misty ledge
#

I've been trying to get started with the Raspberry Pi high-quality camera. Is there a good, up-to-date "getting started" guide for it? I found a PDF called "The Official Raspberry Pi Camera Guide" with a publication date of 2020. However, it seems to be out of date, because it uses the raspistill and raspivid command, which are deprecated and have been replaced with libcamera-still and libcamera-vid.

There are a couple of things in particular that I'm trying to find out:

  1. libcamera-still seems to take about 4-5 seconds worth of video, even though it only outputs a single still frame. Why is it taking so many frames? I was hoping for a command that would just take a single picture, more-or-less instantaneously.

  2. Is there any reasonable, non-frustrating way to focus the camera on a headless Raspberry Pi? Right now, I'm taking a frame with libcamera-still (which takes 4-5 seconds, as mentioned), then I scp the jpeg to my laptop (which takes about 13 seconds over WiFi) and view it. Then I move the focus ring a little, and repeat the process. This isn't really great. Do I pretty much need to attach a monitor (and use the full, not "lite", version of Raspberry Pi OS) in order to make focusing practical?

storm wagon
#

I forgot how I got mine to work but I know it uses libcamera and I'm using a phone app called RaspController to see through the camera. Works great, though I still need to take shots to make sure it's perfect.

charred yacht
#

Does anyone have recommendations for free dynamic DNS provider? We have a game server and want to access it, done all the port forward stuff just need to get a domain name for it.

faint sparrow
#

Also you can get free domains on register/amen
They also weirdly pay you to register domains
Although the cash out is about 3 months long

charred yacht
#

I've never heard of it

#

But I can understand why they do that

#

1 probably wanting to send/rent ipv4 addresses (good investment if you have the monies)
2 probably wanting to have bigger share of domains so they can challenge Google DNS

broken shuttle
#

Cloudflare is one of the biggest cloud providers there is. They do hosting, DNS servers, and the like, but they aren't as public-facing as Google and Amazon.

rotund pivot
#

and CDN

ruby night
#

@torn frigate unfortunately, I have to go offline -- hopefully someone else can continue with help. Good luck.

#

BTW -- I have never had that blinkatest fail after following the guide 😉

torn frigate
#

All good! I think I found the issue.

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I'm using a 240x240 display and the driver may be conflicting

#

on the SPI

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dtoverlay=spi1-3cs should work

slate glen
#

so i got alpine linux running on my pi zero.. but i didn't realize it uses an in memory read only filesystem... how or what is the process for side loading packages and customizing the kernel

upper wagon
#

Hey, question about fbtft. On non-rpi sbcs is it possible to install the fbtft devices thing on a kernel later than 5.4? Or like, how would you go about setting up the device overlays? I was taking a look at this and wondering if the memory registers within init would apply to the actual SBC itself or just the display

spice kayak
#

Late but to add to the recommendation, cloudflared tunnel has been useful. It acts as if you have a vpn. For example you name your server mastodon.xyz.io and it sits at 10.0.0.10 then after you configure cloudflared with mastodon.xyz.io, your team can visit mastodon.xyz.io and cf handles the public facing IP address. You don't need to do anything to the 10.* or attempt to change your pf rules. Tunnel became a free product in 2023; which is why I didn't really explore it before.

torn frigate
#

My code is throwing an error ( "Adafruit_BME680_I2C' object has no attribute 'data_ready' error. ) and if someone out there could give it a once over for debugging I'd appreciate it. I'm a total novice at all of this.

For some background on what I'm doing - I'm choosing to only use the BME680s gas/pressure/altitude, and im basically ignoring the duplicate temp and humidity data since I have a SCD-41 already set up. I don't mind all of the data posting to the terminal, but I'm just choosing to transfer only the gas/pressure/alt. to ada.io.

steady rose
#

there is no data_ready. is that code example from somewhere?

torn frigate
#

The code was altered from a DHT temp/humidity sensor found on GitHub Adafruit. I don't have the link at the moment.

#

But yesterday, another member of the discord worked with me to transform it to work with the SCD4x

steady rose
#

libraries will vary. not all will have the same features, etc.

#

so the data_ready property won't be in everything

#

are you trying to rate limit the readings/posting of the data?

torn frigate
torn frigate
steady rose
#

you'll need to for the code to work, since as is, it's syntax error

torn frigate
#

Alright I just wasn't sure if it needed to be replaced by something or not.

steady rose
#

can use a simple time.sleep(15) to handle to data rate

torn frigate
steady rose
#

ah, yep, ok, see it now

#

yep, so just remove the if bme680.data_ready conditional check

# 
while True:
   read data
   send data to aio
   time.sleep(15)
#

and for read data with the bme680, no need to check a data_ready property

torn frigate
#

once I remove the if statement I would have to align the indentation under the while True, correct?

steady rose
#

yep

#

that's basic python use of white space thing

torn frigate
# steady rose that's basic python use of white space thing

Awesome- everythings working. I supposed I should have tried deleting it first, but I strongly (and wrongly) assumed that something else would need to take its place. All data is posting in the terminal and it's feeding into ad.io perfectly.

It is printing twice in the terminal but I'm sure I can figure out a fix there

#

I'll likely up the interval as well. Do you know the limit in seconds I can do?

steady rose
#

i think it depends on account level, like free vs. paid

#

should be shown somewhere on AIO

#

basic data rate = 30 / min
plus data rate = 60 / min

torn frigate
#

I'll assume I could make the output data once per 5 minutes, 10 minutes, hour, etc even? I'll just have to denote that in seconds.

steady rose
#

yep. the rate limit would work in the other direction - it would limit the fastest available post rate.

#

like can't do once per second with a 30 / min limit

#

for anything above the rate limit (slower posting rate), there is no limit

#

the only thing to consider there is data retention

#

basic = 30 days storage
plus = 60 days storage

torn frigate
#

Perfectly fine. Just for home monitoring

steady rose
#

cool. yep. perfect use case for AIO!

#

at the basic level also

torn frigate
#

Once more question for you - what block would be best for outputting particle count data on the PMSA003I?

For example: you could have each reading (ie: .3um ,.5um ,1.0um, 2.5um, 5.0um, 10um) go into separate feeds. That may be the only way to do it anyways...

steady rose
#

yep, each in a separate feed.

upper wagon
#

Hey, question about fbtft. On non-rpi sbcs is it possible to install the fbtft devices thing on a kernel later than 5.4? Or like, how would you go about setting up the device overlays? I was taking a look at this and wondering if the memory registers within init would apply to the actual SBC itself or just the display

thin pelican
#

Hey guys.

Pi400 > cyberdeck hat > hyperpixel4

No current issues with the hat/hyperpixel problem. Pimoroni long since fixed that conflict but it's a kernel thing that's current only present in raspbian.

The point of the project was a little retro-ish cyberdeck. The problem is raspbian hates me and I want to build a kali or parrot for it, or even just a daily driver debian build with a good suite of tools installed is fine... but after a year of trying (maybe missing the obvious) I can't get kali/parrot/etc to push to the hyperpixel. Someone in the parrot discord suggested recently to use what's in the rpi kernel to build parrot but tbh that's over my head.

paper flower
paper flower
# thin pelican Hey guys. Pi400 > cyberdeck hat > hyperpixel4 No current issues with the hat/h...

For Kali/Parrot, this issue likely applies: https://github.com/pimoroni/hyperpixel4/issues/140

Not sure what kernel changes are needed but, you may be able to do some more digging to find out.

GitHub
Doesn't work on anything other than stock Raspberry OS, please fix ...

IT seems like the packages required are only available if you install stock Raspberry OS. I tried installing this on the 1.5 build of Pimiga (which I believe is Raspberry Pi OS lite) as well as mul...

thin pelican
paper flower
#

That, I can't answer, unfortunately as I've not dug into that side of things for RPi. I would hope that the necessary changes are available in a mainline kernel (or loadable as modules) but, there is a possibility that you'd have to compile a custom kernel, including the needed changes from Raspian. What Pi version are you using? I might have some time to look into it on the weekend but only have a 3B+ handy.

zenith crystal
#

TIL - I was having issues with a couple of new Seesaw-based boards and changed the I2C baudrate (i2c_arm_baudrate=400000) and all the problems disappeared

i made a note of this in the forums, but i think this needs to be somewhere in the Pi FAQ maybe?

humble marsh
zenith crystal
#

yes

#

i haven't tried it against my CRICKIT yet, but for both the new I2C Gamepad and NeoPixel boards, problems ☁️

zenith crystal
humble marsh
dusk flower
#

hello!

#

I was thinking... can I use the FireTV Ethernet adapter on the PWR port of the PiZ2?

humble marsh
dusk flower
zenith crystal
dusk flower
paper flower
#

Quick question for you on VESA specs, specifically DisplayPort (but I bet it's a blanket policy on all of em): Do you know what sort of policies/restrictions govern their use for open source projects? I know that x.org and likely Wayland have a good relationship with VESA and offer contributors limited access to the spec. My suspicion therefore is that implementation is OK (for those with access) but not original spec doc distribution. Does that sound right?

broken shuttle
#

It's... hard to say actually. I am a member through work, so I might be able to send them an email. What part(s) of the spec are you wanting to implement?

paper flower
#

I am planning to implement a USB-C DisplayPort AltMode source and sink, along with some signal processing. The overall goal is similar to what is now being billed as "spatial computing" after Apple's announcement - that is, taking one or more video signals, agnostic of source, and "placing" them in space around the user.

#

My implementation will be primarily FPGA based, for signal processing.

broken shuttle
#

Well, you have your work cut out for you then. DP is not simple to implement, let alone from scratch.

paper flower
#

I wouldn't think so. It should be a good learning experience, even if I don't succeed. I'm mainly from the "squishy" software engineering background so, will be working my way up to it through other implementations (probably first being MPI I3C Basic)

thin pelican
#

Anyone install bettercap on raspbian before

thin grail
#

Hey guys. I was wondering if I can get some help with this

#

I don’t fully understand code

#

I need it to give me gps coordinates that I can then transmit via radio

#

Ideally I need this done in the next hour or so

#

(i do have until tommorow but we need to test tommorow

#

import serial
import pynmea2

def parseGPS(str):
if str.find('GGA') > 0:
msg = pynmea2.parse(str)
print "Timestamp: %s -- Lat: %s %s -- Lon: %s %s -- Altitude: %s %s" % (msg.timestamp,msg.lat,msg.lat_dir,msg.lon,msg.lon_dir,msg.altitude,msg.altitude_units)

serialPort = serial.Serial("/dev/ttyAMA0", 9600, timeout=0.5)

while True:
str = serialPort.readline()
parseGPS(str)

#

I have found this but again

#

I dont full understnad it enough to modify it

rotund pivot
#

@thin grail I'm not much help on the Pi side, but just to make sure... is the GPS hardware on the Raspberry Pi RFM69 receiver and not on the RP2040 RFM69 sender? It would be a different library to run on the RP2040.

thin grail
#

I think I figured it out

#

Will test tomorrow

misty ledge
#

Does anyone know off the top of their head why the Raspberry Pi has five I2C buses:

crw-rw---- 1 root i2c 89,  1 Jul  9 19:31 /dev/i2c-1
crw-rw---- 1 root i2c 89, 10 Jul  9 19:31 /dev/i2c-10
crw-rw---- 1 root i2c 89, 11 Jul  9 19:31 /dev/i2c-11
crw-rw---- 1 root i2c 89,  2 Jul  9 19:31 /dev/i2c-2

I had thought it just had two I2C buses, and I thought bus 0 was reserved for use by VideoCore, so I had thought it might not show up under Linux. Really I was only expecting to find /dev/i2c-1

#

OK, it looks like i2c-10 is for the display and camera ribbon connectors. Still searching for what i2c-2 and i2c-11 are. I suppose it doesn't really matter, since I'm pretty sure the one I want (the i2c bus exposed on the 40-pin connector which is not reserved for the HAT EEPROM) is i2c-1.

waxen valve
#

where a single i2c controller is shared over multiple pins

#

what does ls -l /sys/class/i2c-adapter report?

misty ledge
# waxen valve what does `ls -l /sys/class/i2c-adapter` report? 
lrwxrwxrwx 1 root root 0 Jul 10 19:16 i2c-1 -> ../../devices/platform/soc/3f804000.i2c/i2c-1
lrwxrwxrwx 1 root root 0 Jul 10 19:16 i2c-10 -> ../../devices/platform/soc/3f205000.i2c/i2c-11/i2c-10
lrwxrwxrwx 1 root root 0 Jul 10 19:16 i2c-11 -> ../../devices/platform/soc/3f205000.i2c/i2c-11
lrwxrwxrwx 1 root root 0 Jul 10 19:16 i2c-2 -> ../../devices/platform/soc/3f805000.i2c/i2c-2```

So I guess this is saying that `i2c-0` and `i2c-10` are reached via `i2c-11`?
waxen valve
#

yeah, i2c-0 and i2c-10 are virtual controllers
when you try to use one, it will switch the gpio muxing around, and then i2c-11 does the real request

misty ledge
#

OK, thanks!

waxen valve
#

if you use i2c-11, youll wind up on a random set of pins

#

whichever of 0/10 was used last

misty ledge
#

OK, I did a little more digging, and I think I have it all figured out now:

/dev/i2c-1   available for user on 40-pin connector
/dev/i2c-2   HDMI connector
/dev/i2c-10  camera and display connectors
/dev/i2c-11  implementation detail for i2c-0 and i2c-10```
#

(This is for Raspberry Pi 3, at least.)

waxen valve
#

i2c-2 also depends on if your using fkms or kms

#

with legacy or fkms, the firmware is in control of the hdmi i2c port

#

but with kms, linux is in control

thin pelican
#

Anyone have issues with usb ssh hanging on pizero?

broken shuttle
#

Sounds like a power issue to me (i.e. you need to plug it in to a powered hub that can deliver at least 2A to a single USB port).

thin pelican
broken shuttle
#

Uhh yeah you won't be able to power it directly from the Pi 400.

#

Every generation of full sized pi since the 2 has drawn more than is practical from USB. So drawing another amp or two isn't going to work reliably.

thin pelican
#

The other issue of course is that they designed the pizero so that only one usb port is accessible at a time

#

Idk who the genius that okayed that was. 🤷🏼‍♂️

dusk grotto
#

Anyone know how I can format a 128gb to fat32 on raspberry pi os?

humble nova
#

Im no expert, but isnt FAT32 up go 32GB and you'd need exFAT?

wraith grove
#

fat32 is not what I would use to host an os past windows 98 (and the 2-4G file limit is irksome)

humble nova
#

I understood the question as format FROM raspberry, not FOR hosting its OS, but definitely agree with the message above

waxen valve
#

rpi open firmware

zenith crystal
#

(proud user of linux since Slackware 0.99 😈 )

dusk grotto
dusk flower
dusk flower
dusk flower
broken shuttle
dusk flower
broken shuttle
#

Not necessarily.

dusk flower
broken shuttle
#

Ah I see

dusk flower
#

so yes, one could use either .fat or vfat, and if explicit -F is not provided, it'll just assume the best FS suited for the partition.
nice to see they kept compat, tho.
helps with legacy install scripts.

unkempt cave
#

anyone know how to make a copy of a pi's sd card or create an custom image file from adjustments you made?

#

i tried using win32 disk imager but since im using a 64gb sd card its making an image file that 64gb

broken shuttle
#

Yeah because it's a byte-for-byte copy.

#

Is there a compression option?

unkempt cave
#

no i dont think so

broken shuttle
#

Well, clonezilla can definitely do it.

waxen valve
tawdry nimbus
#

Question, I am trying to install an Adafruit Mini PiTFT - 135x240 on a raspi zero. However, I keep getting an error message “apt failed to compile st7789v drivers!” Any ideas on how to fix?

tawdry nimbus
#

I followed the instructions on the product page and seem to be stuck. any advice would be appreciated

rancid kindle
tawdry nimbus
#

I don’t know tbh

#

I’ll check back in soon.

rancid kindle
tawdry nimbus
#

I used this code from the adafruit website. The last command gives the error.

crisp lion
#

Hello everyone 😄 , hope this is the right thread to ask my question
I generate different LED patterns based on (real time) user input. Is there a graph/ formula for calculating the time needed to write to the whole strip based on how many LEDs it has?
I'd like to know what's the maximum amount of LEDs I could get away with until the write operation takes too long and it doesn't feel snappy/ real-time-y enough

zenith crystal
crisp lion
#

I have the strip connected directly to a pin on a raspberry pi 4 (one of them PWM pins by the way)

zenith crystal
#

still should be "stupid fast" - this is running via i2c (crickit hat) with a 50ms delay

crisp lion
#

thanks! The reason I am asking is because I'd like to place an order for the circuit to be made and I need custom spacing between the LEDs

#

and would hate to ask for too many and cause a delay 😅

zenith crystal
#

i don't know about wiring the WS28xx LEDs together personally, but the strip from Adafruit works just swell 😀

crisp lion
#

anyways, would the graph and the function be linear? how many LEDs until it takes 0.1 - 0.15s to write to the strip?

#

yeah, I have the 2812b I think, very happy with it 👍

zenith crystal
#

.1 second is a LONG time, so i wouldn't worry too much about it

#

i had sub 10ms writes for 30 LEDs easy

crisp lion
#

ah, nice!

#

then it looks like 400-500 LEDs would be the max

#

and 600 would be pushing it a bit too hard 😅

#

currently at just below 300, but will experiment and report back

zenith crystal
#

that's... a lot lof LED's 👀

crisp lion
#

yeah I know, I'm a little weird like that

clever moon
#

hi i was trying to use this:https://learn.adafruit.com/adafruit-pca9548-8-channel-stemma-qt-qwiic-i2c-multiplexer i2c multiplexer with my raspberry pi 4 but when i try yhe first example code for it after installing blinka and the library for it i get this error File "<string>", line 16, in <module>
File "/usr/local/lib/python3.9/dist-packages/adafruit_tca9548a.py", line 62, in try_lock
self.tca.i2c.writeto(self.tca.address, self.channel_switch)
File "/usr/local/lib/python3.9/dist-packages/busio.py", line 203, in writeto
return self._i2c.writeto(address, buffer, stop=stop)
File "/usr/local/lib/python3.9/dist-packages/adafruit_blinka/microcontroller/generic_linux/i2c.py", line 52, in writeto
self._i2c_bus.write_bytes(address, buffer[start:end])
File "/usr/local/lib/python3.9/dist-packages/Adafruit_PureIO/smbus.py", line 303, in write_bytes
self._device.write(buf)
OSError: [Errno 121] Remote I/O error

Adafruit Learning System
Adafruit PCA9548 8-Channel STEMMA QT / Qwiic I2C Multiplexer

Use up to 8 same-address I2C devices connected to one microcontroller with zero soldering!

#

i cant seem to figure out the problem
the multiplexer seems to be turned on because i see a small green led

midnight flume
#

the small green led on the multiplexer means the module is getting 3V power. it's a power LED.

clever moon
#

ok

#

what does the error mean

zenith crystal
#

it means you can't write to the I2C bus or there's nothing "attached" - what does /sbin/i2cdetect -y 1 return?

clever moon
#

its empty

midnight flume
#

double check the pin connectors and make sure they're not bent. they're small and it's possible to squish one to the side if not properly inserted which can cause IO failures.

#

Unless you're soldering to the I2C pins directly?

clever moon
#

its soldered on the multiplexer side and inserted into a breadboard on the raspberry pi side

steady rose
#

can you post a photo of this setup?

midnight flume
#

ok and you're sure SDA and SCL are wired correctly? a picture of your setup could help.

#

jinx

steady rose
#

no addresses are showing up in the i2c scan, so most likely a connection issue

midnight flume
#

if it's not scanning then the module i2c address itself isn't connecting. an i2c scan might help figure out if the board itself is connecting correctly before scanning for multiplexer channel scans.

steady rose
#

yep. the address of the PCA itself should always show up in the scan, regardless

clever moon
#

the first one is the multiplexer so the red is vcc, white is - , brown is scl, blue is sda, and green is rst (rst not connected to anything)

1.jpg 2.jpg 3.jpg
#

its also probably a 10 foot cable between the pi and the multiplexer

steady rose
#

cable length could be an issue

#

thanks for photos

#

can you post one showing soldering on back side here:

image.png
#

and how are the wire splices being made under the blue tape? are they soldered?

image.png
clever moon
#

yes there soldered under the tape

#

twisted the wire and soldered

steady rose
#

if not, what all do you have in the way of STEMMA QT cables?

clever moon
steady rose
#

thanks. that soldering looks fine.

image.png
clever moon
#

i bought some ones on amazon from sparkfun to connect all the sensors to the multiplexer board but i soldered the wires directly on the multiplexer

steady rose
#

if you have a spare STEMMA QT cable, could try connecting the PCA to the Pi via this connector:

image.png
#

and then run the i2c scan again and verify the PCA address shows up

clever moon
#

ok

#

ill try that

steady rose
#

also - good idea to remove all the things connected to the PCA outputs for now

#

first - just want to see if we can get the Pi to even see the PCA

#

via i2c scan

clever moon
#

ok sounds good

steady rose
#

i just connected one to a pi. here's what the scan should look like. the expected address is 0x70

Screenshot_from_2023-08-01_14-55-47.png
rancid kindle
#

@clever moon did you enable I2C on the Raspberry Pi using raspi-config?

clever moon
#

yes i have

#

ok

rancid kindle
# clever moon yes i have

have you tried running the program as root? You shouldn't need to and if it's a permissions issue I'd expect different errors, but just in case...

clever moon
#

unfortunatley still nothing

waxen valve
clever moon
#

i guess there must be something wrong with the board because when i connected a stmma cable to the other end of the multiplexer and attatched my smaller multiplexer i had bought the smaller one is being recognized

clever moon
#

like how do i use the multiplexer to communicate

#

ive tried but i cant seem to figure it out

#

nvm i got it working

rigid abyss
#

I'm curious about reading the magnetometer on a bno085 with python on a rpi via i2c.
I have it wired correctly and see 0x4a when I run i2cdetect. But when running the sample code or other code, it's unable to read the magnetometer.

umbral sable
rigid abyss
#

OSError: [Errno 121] Remote I/O error

#

The address and everything else is correct according to the documentation.

#

As listed here

steady rose
rigid abyss
#

I did, same error

#

I can read feom the other sensors, not the mag

steady rose
sweet gorge
#

hi all, I need general linux help

#

this doesn't necessarily apply to RPi's but I'm at the point of "ask strangers on the internet" as I'm now days into messing with systemd

#

and ChatGPT helped a lot, but then ChatGPT did what it is want to do and stopped being helpful

frail spindle
zenith crystal
#

(I seem to be pointing to other people's answers today... 😃 )

sweet gorge
#

Fair point, apologies.
I am currently trying to get a shell script to run at launch that puts minecraft into a screen and that is about it, it runs fine when manually executed. I've tried just about every approach to writing the service file and still end up with it doing absolutely nothing, the logs just say "failed" because it retried 10 times, I've put in a sleep timer and done all the magical voodoo. I'm beginning to think that calling for screen is the problem, and I am unsure if I just point to executing java and being clear on launching spigot (minecraft server client).

#

I am an AWS architect by trade, and this is the first time systemd hasn't been doing a simple task, which has thrown me for a loop because it's intrinsically point and shoot for all the development I do. So this is murky territory.

zenith crystal
#

ah - you have to have X (or Wayland) running first, which actually doesn't occur during service execution phase

sweet gorge
#

no X, this is an AWS EC2 instance.

zenith crystal
#

"screen" requires an X server

sweet gorge
#

screen itself is just so you can park an application in the background and recall it to terminal

frail spindle
#

Wait

zenith crystal
#

screen is "text"

frail spindle
#

You have screen

sweet gorge
#

si

frail spindle
#

On a shell script

sweet gorge
#

yeah, work's just fine

frail spindle
#

that is supposed to be launched by a systemd service

#

Systemd services do not have an interactive console, terminal, etc

#

So, I doubt screen is going to work

zenith crystal
#

are you trying to run the minecraft server or client?

frail spindle
#

You will need to manage your server with a pidfile or something

zenith crystal
#

regular minecraft is a graphics-based program and requires X or equivalent to run - screen is just a text-based multi-terminal like program and also needs at least a console output

sweet gorge
#

oh no this is server

#

sorry, shoot i must've not communicated that

zenith crystal
#

do you have any error output? what does systemctl status <your service name> say?

#

note, i've not ever done this but a quick search turned up the nogui option ...

sweet gorge
#

yeah I am runing the proper launch

#

as it will run on it's own just fine in the start.sh script i made

zenith crystal
sweet gorge
#

LAWDY LAWDY

zenith crystal
#

just regular search, amigo

rigid abyss
shy saffron
#

Anyone know if it's possible to access the rPi's USB bus from the GPIO header? Doesn't look like it but figured I would ask.

turbid rivet
waxen valve
shy saffron
waxen valve
#

for the pi4(00), zero and model-a's, the D+/D- are directly exposed at a usb port

#

for the 1b/2b/3b, there is a usb hub connected to those pins, and you cant access them directly

opaque wagon
#

I'm doing an I2C dump of an Arduino being a peripheral device on the Raspberry Pi, and there are random 0x80s everywhere - is this a sign of the bus capacitance being too high since it can't pull down the line fast enough?

#

Funny thing is that is my logic analyzer is read the signals just fine (no 0x80 in pulseview)

#

(The cable is a bit long - an Adafruit T-Cobbler through a level shifter to the other side of the breadboard)

#

Here is a picture of the I2C dump (the number of 0x80s change every dump)

image.png
#

And here is PulseView

image.png
#

ok slowing down the I2C bus "fixed" the problem!

umbral sable
#

In the Pulseview graph, the short clock pulse right at the start of the read operation looks a bit suspicious. Possibly the slave is clock-stretching on the response because it couldn't respond fast enough to the read command.

#

But slowing down the bus helps with all sorts of potential issues.

waxen valve
#

the rpi also has a clock stretching bug

#

Recollection is that only the new controllers are fixed in case it broke something else. In each case there is a pin muxing option to map a new controller onto the pins of BSC0 or BSC1. (BSC6 in the case of GPIOs 0&1 alt5, or BSC3 for GPIOs 2&3 alt5).

#

from what i remember (and skimmed over here), the i2c controller in the vc4 era (pi0-pi3) had this bug

#

on the bcm2711, they fixed it on the new controllers, but didnt want to risk causing new problems

#

so they left the old i2c controllers broken

ionic fable
#

So I am trying to install witty pi hat l3v7 onto my pi 4 and it installed fine, but my pi still cant find the directory

crisp drift
broken shuttle
#

Did you log out then back in?

crisp drift
#

Yes I rebooted

#

The rights for the group gpio on /dev/mem keep resetting though

broken shuttle
#

Oh, you'd have to set that via udev. You can't just change permissions for things in /dev since those are populated during runtime and are not real files.

#

Did you add yourself to the gpio group?

crisp drift
#

Yes

#

I might just try using setuid or something

crisp drift
waxen valve
crisp drift
waxen valve
#

setuid only works on compiled binaries

crisp drift
#

Ah that's stupid from me then

waxen valve
#

why does this library need to open /dev/mem ?

crisp drift
#

I think to write to the LED? It's on pin board.D18

waxen valve
#

thats what /dev/gpiomem is for

#

which it opened successfully

crisp drift
#

I thought that was weird as well, but I don't think I'm doing anything weird

afbeelding.png
waxen valve
#

where is the source for that neopixel library?

crisp drift
waxen valve
#

and then neopixel_write?

crisp drift
#

What do you mean?

waxen valve
crisp drift
#

I guess it comes with Adafruit CircuitPython?

waxen valve
#

i think the problem, is because its using the hardware pwm, in serializer mode

#

and there is no proper driver in linux to allow that from non-root

crisp drift
#

Okay, I'll try to just use root then

turbid rivet
zenith crystal
#

is your user in the gpio group?

waxen valve
waxen valve
zenith crystal
#

hm - i just ran a PWM servo off of D18 without any problems

#

on a Pi 3

#

oh - did you add dtoverlay=pwm,pin=18,func=2 to the /boot/config.txt

also, i just looked at the the Neopixel code and it's setting up the pin parameter as a digital I/O port, not PWM self.pin = digitalio.DigitalInOut(pin) self.pin.direction = digitalio.Direction.OUTPUT

#

and the error says "SPI transfer error" - i have SPI turned on via the config - maybe that's the difference?

crisp drift
#

SPI transfer error happened when I tried using the SPI pin, according to the first link I sent. I think that is a different problem than the /dev/mem, which happens when I use the normal pin

crisp drift
zenith crystal
#

well, it won't hurt

crisp lion
#

hi guys I have a quick question;

#

let's say I have a neopixel strip with 1000 LEDs on it

#

but only want to use 100 LEDs and that's what I pass in as the second argument when instantiating the NeoPixel class, e.g. NeoPixel(board.D12, 100)

#

would the 900 dormant LEDs cause any write delays or will it be as fast as if there were only 100 LEDs in the strip?

turbid rivet
#

Not if you’re using the first 100 LEDs.

crisp lion
#

yeah, it's always going to be the first 100 or whatever the number

turbid rivet
#

Your hardware doesn’t really ever see your neopixels, it just spits data into the input. The first pixel takes that data, eats the first pixel’s worth of data, and passes the rest out its output to the next, and the process repeats.
If you only send 100 pixels’ worth of data, the 101st pixel never gets any data, so it sits idle until it does.

crisp lion
#

ah nice! Good to know, thanks!

#

By the way, seems like you know a lot

#

so I'd like to ask you another question

#

I have certain LED light patterns created based on real time user input

#

I was wondering what would the maximum number of LEDs in a strip be possible for the write to take 0.1s?

#

is there like an x/y graph that has latency as a function of the number of LEDs in a strip?

#

Would that function be linear?

#

(I sure do hope it's not a quadratic lol)

turbid rivet
#

Neopixels are typically sent data in a fixed frequency stream of 800KHz, so one pixel takes about 10us per color channel. 100 RGB pixels would require ~3ms for a single data transfer, and 1000 RGBW pixels would require about 40ms.

#

The sending of data to neopixels is basically linear, though the more significant delays generally come from more complex computation of which pixels are assigned what colors in your software.

crisp lion
#

oh right; I have the ws2812b

#

yeah, that's exactly what I have discovered... 😅

#

so you're 100% correct

#

So I'd be looking at about 333 LEDs for a 0.1s reaction time?

turbid rivet
#

Assuming the only constraint is the transmission speed of the data, you’re probably off by a factor of 10.

crisp lion
#

great! 33.3 LEDs it is 🤣

turbid rivet
#

More like 3333.

crisp lion
#

oh wow!

#

that's great

#

In any case, I'm just curious; the neopixels are on a single strip, so it kind of makes sense that the data signal has to go through them all (like going through a list of data)... But is it possible for the data to be sent only/ directly to the pixel that needs it?

#

as in... accessing a pixel like you would data in a hash map rather than having to loop through a list of data

turbid rivet
#

Nope. Hardware limitations.

crisp lion
turbid rivet
#

From a software perspective, you can change a single pixel however you like, thanks to the abstraction layer the adafruit libs provide

crisp lion
turbid rivet
#

Exactly.

crisp lion
#

so it's not like I'm saving any time

turbid rivet
#

Again, writes are generally not the primary constraint.

crisp lion
#

I understand; but it's still great news for me; I thought the max was 333 LEDs and not 3333 LEDs

#

I'm not great with the mini/ mili/ micro/ nano etc unit prefixes so that's why I was off by x10

#

Right, so given this excellent number which is 10x higher than I expected

#

if my real-time user input system is choking and LEDs are flickering/ lagging whatever, it means that my program sucks rather than hardware?

waxen valve
#

with the DPI hardware on the rpi, you can hw accelerate writing to 24 neopixel strings at once

#

with 24 seperate strings, an example set of 3333 LED's, becomes 24 sets of 138 or 139

#

so, it now only takes ~139 writes to update the entire set, rather then 3333, 1/24th the update time, or 24x the refresh rate

crisp lion
#

wooooow that's excellent!

#

now... could I do that splitting on a raspberry pi? I'm not even sure they have 24 pins

waxen valve
crisp lion
#

wow!

waxen valve
#

specifically, the 8 red/green/blue ones

crisp lion
#

@waxen valve would it be ok if I DM'd you?

waxen valve
#

lets keep it here, so others can also read it later if they want to do the same

crisp lion
#

😢

#

aight 😅

waxen valve
#

basically, the DPI on the rpi takes a "frame" of "pixels", each pixel is 32bits, containing 3 sets of 8bit color, and 8 wasted bits

#

but all its really doing, is taking 24bits out of an array, presenting it on 24 pins, waiting 1 clock cycle, and repeating

#

who says you cant put a stream of neopixel commands into bit0 of each pixel?

#

who says you cant put 24 seperate neopixel commands, one stream into each bit

turbid rivet
#

It’s a little more complicated than that, but that is possible.

waxen valve
#

one limitation of the hardware, is that while hfront and hbackporch can be 0, hsync has a minimum of 1

#

so, at least 1 "pixel" out of every scanline has a 0 for all 24 bits

#

and same in the vertical, vfront and vback can be 0
but vsync has a min of 1, so for 1 full scanline, all 24 bits will be 0

#

but you can freely decide what the w and h are, up to 2047 i think

turbid rivet
#

But hey, if you’re using 24 lines, and each scan line is what, 640px across? That’s a lot of pixels

waxen valve
turbid rivet
#

I guess the better question is, does your application need this level of hardware hacking to do what you want it to do?

waxen valve
#

so, the neopixel protocol, what does it take to write to one pixel?

turbid rivet
#

24 bits @ 800KHz

waxen valve
#

and each bit is sent how?

#

by the length of a pulse?

turbid rivet
#

Yup

waxen valve
#

would 0.4uSec and 0.8uSec work? does it need to be 0.85uSec? and 0.45uSec?

turbid rivet
#

Honestly, if you need a decent frame rate on a large display of pixels, it’s much easier to use dotstars or hub75

waxen valve
#

assuming you can fudge the timing some
lets make a DPI pixel last 0.4 uSec
a single bit, is 3 pixels, 100 for a 0
110 for a 1

#

so 24 bits, is 72 samples/pixels

#

a 2016 pixel scanline, contains color data for 28 neopixels

#

then you have a stray 0.4uSec pulse, that might confuse things...

#

if you use all 24 bits of "color", with a 2016 pixel scanline, thats 672 neopixels refreshed, in just 1 scanline

crisp lion
#

Hmmm this is a bit hard for me to understand to be perfectly honest 😅

waxen valve
#

and handily, the vsync pulse will get interpreted as the reset

waxen valve
#

but some very rough math, says you could refresh 1,344,000 neopixels in a single command on the dpi

crisp lion
#

lol

waxen valve
#

and such a refresh, would only take 0.067 seconds

#

so, you could update such an array at ~14 fps

crisp lion
#

right... I'll definitely keep the conversation up till now in mind, but could we go back to normie land for a sec 😅 ?

waxen valve
#

yeah, the problem, is getting neopixels into the hands of somebody that can write this code, and making it easier for the avg user

#

i should probably get a heap of neopixels at some point, and try that

crisp lion
#

going back to what you mentioned about writing to 24 strips of neopixels at once...

#

I thought I could use only one PWM pin on a rpi at a time

waxen valve
#

the PWM controller can drive 2 pins at once

#

the DPI controller can drive 24 pins, and can also be abused to control neopixels

crisp lion
#

speaking of DPI abuse... Is there an un/official library that would let me use Neopixels on DPI pins?

waxen valve
#

from what i know of the pwm controller, it can do 2 pins at once

waxen valve
crisp lion
waxen valve
# turbid rivet 24 bits @ 800KHz

oh, and looking closer at the diagram, the bits differ from 110 and 100, the start/end never change
so encoding a color into the pixels, only involves updating the middle bit

waxen valve
#

if you know C, have a logic analyzer or scope, and some time, you could do it

crisp lion
#

too bad I have neither 🤣

crisp lion
waxen valve
#

my scope isnt able to handle usb2 speeds (480mhz), but i was able to get usb working, with enough blind guessing

#

without a scope/la, you just have to assume the code is working, and then guess when it doesnt work

crisp lion
#

thanks for all the answers and getting involved, appreciate it guys @turbid rivet @waxen valve

waxen valve
#

an even more working-blind case, i could write all of the neopixel code, test it with a scope, and never actually test it on real neopixels

#

and then see what happens when somebody else runs it for the first time, heh

crisp lion
ornate bluff
#

anyone know why a raspberry pi 4 would be hitching over SSH on a local network

waxen valve
ornate bluff
#

wifi but not much else going on on the network

waxen valve
#

there have been issues with the wifi power savings stuff

#

if you run ping pi4 in another terminal, does the ssh get better?

#

leave it pinging

ornate bluff
#

Yeah it seems like it. Interesting

waxen valve
#

the way its supposed to work, is that when the wifi is idle, client basically just turns the radio off entirely

#

and the router will hold packets for a few seconds

ornate bluff
#

but the pi is over aggressive in turning off?

waxen valve
#

and the radio will come back on every now and then, to check in

#

then you dont need ping to keep it awake

ornate bluff
#

hm I'm planning on using ethernet anyway eventually I was just setting it up at my desk and trying to figure out why it was acting off. That makes sense, thanks!

paper carbon
#

bit of a doozy here, but
I'm running a pi with a pitft, and it runs a single fullscreen GUI, like a point of sale / kiosk
right now, it runs on a full X11 stack using LXDE, but I'd like to run it as "minimally" as possible

is there an easier way to configure this (like, a wayland / X11 compositor built for kiosk apps or such)?
and, is it possible to get this running in docker? (prefferably the display server as well)

#

the gui is built with Java Swing

paper carbon
#

is it possible to run the pitft on wayland?

#

i can install weston, but it hangs at initializing drm backend
I'm not too familiar with how the linux kernel, wayland, and x11 work together

ornate bluff
#

Is there a way to share the Wifi from a raspberry pi with the ethernet port in a way that allows other devices on the Wifi to access the ethernet device?

waxen valve
#

ether routed or bridged, depending on your preference

ornate bluff
#

Hmm, I'll try using that bridge guide but reversing the interfaces

#

The guide says that there's no need to add wlan0 to the bridge since the AP package will do it, but I'm using the wlan0 as a client, not an AP, so would I just add it with an identical file to the one for eth0 but with wlan0 instead?

ornate bluff
#

Well so it turns out the Pi doesn't support bridging wlan0, but you can use proxy arp to do it but it requires setting up systemd-networkd. for whatever reason every time I try to do so, the pi never connects to the network (or it does and doesn't allow SSH/ping). i don't have a way to see the display of the pi, how can I figure out what's going on? is there a better way?

uneven solstice
#

Hi, I'm trying to set up an ili9486 display on an Orange Pi Zero 3. I'm following this guide: https://learn.adafruit.com/circuitpython-on-orangepi-linux/orange-pi-r1 (I'm aware it's a different board). So far, i2c and SPI are set up (had to edit a file to make SPI work), but the digital pins aren't working, as it's giving an error (this is the code on the page, only change was to use a pin that the board has):

$ /home/orangepi/.mambaforge/envs/ili9486/bin/python /home/orangepi/testeBlinka.py
Hello blinka!
Traceback (most recent call last):
  File "/home/orangepi/testeBlinka.py", line 8, in <module>
    pin = digitalio.DigitalInOut(board.PC10)
  File "/home/orangepi/.mambaforge/envs/ili9486/lib/python3.10/site-packages/digitalio.py", line 165, in __init__
    self.direction = Direction.INPUT
  File "/home/orangepi/.mambaforge/envs/ili9486/lib/python3.10/site-packages/digitalio.py", line 195, in direction
    self._pin.init(mode=Pin.IN)
  File "/home/orangepi/.mambaforge/envs/ili9486/lib/python3.10/site-packages/adafruit_blinka/microcontroller/generic_linux/libgpiod_pin.py", line 55, in init
    self._line = self._chip.get_line(int(self._num))
  File "/home/orangepi/.mambaforge/envs/ili9486/lib/python3.10/site-packages/gpiod/libgpiodcxx/__init__.py", line 201, in get_line
    raise IndexError("line offset out of range")
IndexError: line offset out of range

As I have to set the DC and RST pins, I'm being unable to use the display. OS is Ubuntu 22.04 from the Orange Pi site, as it seems there is no Armbian image for this board yet.

uneven solstice
#

I'm trying to get i2c-2 working on Orange Pi Zero 3, I have enabled the overlay and i2cdetect detects the i2c device, but board says the board does not support it

#

Is the CircuitPython board still supported?

steady rose
uneven solstice
waxen valve
# 
// Specific to controller
#define USB_DEV "/dev/gadget/fe980000.usb"
#define USB_EPIN "/dev/gadget/ep1in"
#define USB_EPOUT "/dev/gadget/ep4out"
#

by opening files like this, you can do usb device stuff from linux userland

#

in theory, tinyusb could be ported to that, and run under regular linux

midnight flume
#

all greek to me, i haven't even booted up a pi in about 3 years. no sense in tagging me for a discussion about pi's. 😉

waxen valve
#

ah

frail sigil
#

noob question, i'm trying to figure out how to run an adafruit example on RPI for the RGB matrix displays... i'm in the current directoy of /rpi-rgb-led-matrix/examples-api-use but i'm unclear on how i actually execute one of the examples?

vocal lava
#

rpi-rgb-led-matrix/bindings/python/samples should have python examples, too

frail sigil
#

thank you!

crystal jewel
#

One thing I am concerned about is the Witty monitors the TXD pin to determine if the Pi is powered up - this is done by monitoring a the pin through a diode and smoothing cap, in theory allowing UART comms to still work; I am wondering if anyone can confirm this works as expected, as my primary case will be to add a pHat that requires UART i want to be sure it will work

the Witty is cheaper than the PiJuice - by a fair margin where I live; I wonder whether there is anything that is better in the PiJuice to warrant the price? I do like that the PiJuice uses fewer pins, and the UART conflict won't happen - but their documentation is a little confusing, so I have other concerns - my use case is to build a fully off grid system that runs purely on battery, but has scheduled power on / off. I am assured by PiSupply that it will work, but their docs say

*The PiJuice provides an onboard intelligent on/off switch allowing you to have control on when the Raspberry Pi will be switched on or off without having to plug or unplug the PSU as you would normally have to do.

Note: Turning on the Raspberry Pi via the onboard intelligent switch only works when the power is provided to the micro USB on the PiJuice.*
(https://github.com/PiSupply/PiJuice#power-management) - however it appears the docs assume you are running the system as a UPS, and not 100% battery powered. But i am assured that if the battery has enough juice, then it will work as required...

#

a second question I have, i need a short micro-usb <-> micro-usb cable; however all I can find are OTG cables - might be a stupid question, but is there anyting preventing you from using an OTG cable as an ordinary USB data/power cable?

I am looking at this cable specifically: https://thepihut.com/products/micro-usb-to-micro-usb-otg-cable-10-12-25-30cm-long

the use case is to connect a modem pHat to a pi-zero; so micro usb - micro usb is required

rigid canyon
#

I'm using an adafruit pi-tft 2.2" with a raspberry pi 0 and I have the little 2.2 tft display at 270 deg. however I 'd like the set HDMI mirrored at 90 deg. Is this possible?

turbid rivet
turbid rivet
waxen valve
#

ive not seen any micro to micro cables

#

i would just use an otg->a adapter, and then an a->micro cable

#

but from what i know, they should exist

broken shuttle
turbid rivet
#

He did, in fact, link that particular micro to otg cable in his own message.

waxen valve
#

but now the fun part

#

how do you know which end is host and which is device? 😄

#

As of Oct 20, 2019 we have the ID pin on the MicroUSB connector tied to GND on both ends, this will help some hosts to force them into OTG mode

#

oh, you dont

#

that will also cause conflicts on some devices, from what i know of the specs

turbid rivet
#

I know of otg plugs that are actually shaped a bit differently from regular usb micro, but that doesn’t seem to be the case here.

waxen valve
#

let me double-check the docs i have...

#

the dwc2 controller has a pair of bool flags in a control register

  • b-session valid, indicates device mode
  • a-session valid, indicates host mode
#

but i think that might only be after you switch modes, and partially init it

#

oh, yes, and each of those is only readable in the corresponding mode

#

but there is another flag, indicating if its in a-device or b-device mode....

#

then you have HNP and SRP, which i still dont understand.....

#

cant find it now, there was a register git that basically make OTG_ID act like an input only GPIO

crystal jewel
crystal jewel
wraith grove
#

I am chatting to someone with a pi 4 that does not boot and has a solid green and red light with nothing but a proven powersupply and sometimes SD card in it. Any chance it isn't dead?

turbid rivet
#

Sometimes SD card? Is there a proper is on the SD card?

wraith grove
#

generically it is often the SD card. for a pi4 the green light should pulse a bit while reading the card, then stuff happens, or on an early error the green light should start making a string of pulses indicating an error state, or it would end up dark as everything is fine and nothing is happening. on a pi2 a missing SD card can generate a solid green light I hear.
for a pi4 to instantly have a solid green light is ?probably a really really bad sign, and may suggest the pi is nowhere near reading the sd card
also a working sd card has been tried to no effect

waxen valve
uneven solstice
#

Hi, I'm having some trouble with BMP280 via SPI. Somewhere in the BMP280 library, it calls try_lock and then it destroys the performance by setting the frequency super low

#

Is there a way to avoid the try_lock from the BMP280 library?

steady rose
dusk flower
#

Bakery photo! 😄

#

Please be kind with Pi2 (aka Licio), it's clinically blind from HDMI, as it's missing L4→L7 🙂

#

now for a serious question: given P2 and P3 were running latest OS versions, is it possible to just shift the respective µSD upwards? 🙂

#

would they be forward compatible?

#

P2 was used with OMV, P3 was running plain RPiOS

waxen valve
waxen valve
dusk flower
waxen valve
#

ahh, how did they go missing?

dusk flower
#

beats me

dusk flower
waxen valve
#

let me get more details...

# 
kernel.img: 32-bit ARMv6 kernel for Pi 1 and Zero.
kernel7.img: 32-bit ARMv7 kernel for Pi Zero 2W, 2 and 3.
kernel7l.img: 32-bit ARMv7 kernel with large memory addressing for Pi 4 and 400
kernel8.img: 64-bit kernel for any 64-bit capable Pi.
#

your fat32 partition needs all 4 kernels if you want it to work on every model

dusk flower
#

yep, they're there

#

lemme try booting with video connected

#

ok, it does boot

#

but no net at this point...

#

ok, switching back to old Pi works, let's see if updating solves anything

dusk flower
#

ok, will try a reinstall of OMV, did a full update and still nothing when using the Pi3.
heck, even the router doesn't see anything attached to the port! it says it's active, but no MAC is listed!

dusk flower
#

how... curious.
Pi3 is listed by arp-scan as "Raspberry Pi Foundation"

#

Pi4 is "Raspberry Pi Trading Ltd"

waxen valve
#

the first 3 bytes differ

waxen valve
dusk flower
#

too late, already bulldozed the install, and don't have a gpio uart at hand, let alone a 15m long one

waxen valve
#

if you have a 2nd pi, you can use that too

dusk flower
#

nah t's ok, it's installing OMV already, and at great speed too

#

also, now the "biggest" job will be reconfiguring mpd in satellite mode, but should be easily doable since last time I set it up

#

nice, raspbian RaspberryOS includes Avahi by default, should simplify setting up a bit by removing the requirements of finding out the IPs at every lease expiration

waxen valve
#

yep

#

but i also have static dhcp setup in my router

#

the pi4 will always be 192.168.2.55

#

you can also clearly see, how the first 3 bytes of the mac changed

dusk flower
# waxen valve but i also have static dhcp setup in my router

yep, planning to do so once I'll have everything in permanent order on the net.
hi2lo, net apparatuses, servers, small devices (TVs, consoles...), PCs and lastly mobile devices, all static leased, with the lowest addresses dynleased, but with MAC allowlist for WiFi

#

also, will try to use a domain I bought instead of .local, so to be able to connect to servers exposed to outside without configuring the mobiles per each domain

waxen valve
#

thats one tricky issue i have

#

my current router doesnt support hairpin nat (accessing forwarded ports from inside)

#

so if i use a public domain and my public ip on http, i wind up at the routers config page, lol

#

so i need to do some fancy iptables stuff in the router, fancy nginx stuff, or just use LAN ip's

dusk flower
#

eh, at this point I just might use the domain for VPN when outside and then access local machine as .local instead XD

waxen valve
#

i also have both .local and .localnet

#

.local is for avahi
while .localnet is my custom TLD in the router, with all of the static IP's

dusk flower
#

Yasss, not only did I finish migrating the boards, I've also managed to make the mpd main/satellite conf IP agnostic with avahi!

delicate dock
#

Anyone using a pine64 board?

velvet rampart
#

if i want to show a battery percentage in w/e linux distro, is there a standard way to hook up the battery to the device over gpio for it to be read automagically over i2c for example? e.g. can i hook up a fairly standard compliant battery replacement (because i notice my battery has a circuit on it) for a mobile phone and hope it produces the results?

#

and a quora user suggested this

"Surprise! The charge descriptor as a circuit is built into the battery itself. It is not a part of the phone as such. If you study a mobile phone battery, you will find a +ve, a -ve and a T or E terminal. This third terminal in the middle tells the charger circuit to shut down once the internal charge reaches a certain level. Malfunctioning of this circuit results in distended (inflated) batteries and charge retaining malfunctions that in some cases have been found to make the batteries explode or catch fire.

This is what goes into a charge controller chip of a cell phone battery. Similar features are seen in batteries installed in digital cameras and laptops."

#

my battery however will be connected to a step up converter circuit which ends up putting out 5v which will be connected to 5v on gpio and grounded. just wondering if anyone here can give me an option to expose the battery status to the os in a way that doesn't involve too many custom scripts or circuits. also very noob user here

fickle rose
#

very long time no see https://adafru.it/5580 and https://adafru.it/4712 exist

Adafruit MAX17048 LiPoly / LiIon Fuel Gauge and Battery Monitor

Low cost Lithium Polymer batteries have revolutionized electronics - they're thin, they're light, they can be regulated down to 3.3V and they're easy to charge. On your phone, ...

Adafruit LC709203F LiPoly / LiIon Fuel Gauge and Battery Monitor

Low cost Lithium Polymer batteries have revolutionized electronics - they're thin, they're light, they can be regulated down to 3.3V and they're easy to charge. On your phone, ...

velvet rampart
#

Hello

#

Do I remember correctly @fickle rose we spoke in general last week?

fickle rose
velvet rampart
tall pollen
uneven solstice
steady rose
# uneven solstice Sorry for taking so long to answer, but just wanted to confirm that setting the ...

if you aren't trying to read the sensor crazy fast, i2c is fine. for spi, in theory, the clock speed should dynamically change for each device, instead of one device limiting overall speed. the adafruit busio library does that here:
https://github.com/adafruit/Adafruit_BusIO/blob/4f899a2dd6db67b4b4d719b3964a6e1dbadca716/Adafruit_SPIDevice.cpp#L286
but it's also possible not all platforms support that and/or other libraries are not doing something similar

uneven solstice
#

I was the culprit (I'm writing the code for the display). Now it's fixed

uneven solstice
#

Evidence the sensor is no longer limiting the display (not shown: the screen's touch detection, it works as a huge button [no coordinates yet])

paper carbon
#

is it worth trying to setup a kiosk mode,
or just auto start with LXDE?

steady rose
#

@tight solar how is the AHT20 connected to the Pi?

tight solar
#

Hello! It’s connected to the bonnet that’s on the pi, here are some photos

IMG_7714.jpg IMG_7713.jpg
#

I’m fairly certain I’m doing something wrong but have not found what yet. The sample code provided for the bonnet works without issue, though the sample code for the sensor gives a Remote IO error

steady rose
#

what OS are you running on the pi?

tight solar
#

Just checked really fast and it is rasbian 11 / bullseye

#

I did verify the sensor itself is picked up by i2cdetect -y 1 so that seems reassuring , I was a bit worried since I brought cables 3rd party it'd be some hardware connection issue but I dont think thats the case thankfully

steady rose
#

cables look OK in terms of wires

#

how long is it?

tight solar
#

its ~8 inches long but I have a few others here that are shorter I can swap out if recommended ?

steady rose
#

that should be OK

#

do you have any other I2C devices?

#

stemma breakouts, like the AHT20

tight solar
#

unfortunately not sorry

steady rose
#

no worries. that was just to provide another sanity check.

#

can you post the full text of the error

#

there should be several lines of text, more than just the "I/O error" one

tight solar
#

For sure 😎 one moment please , let me swap over to get that output copied

#

housefourbee@housefourbee:~ $ python ~/oledScript/simpleAht20test.py Traceback (most recent call last): File "/home/housefourbee/oledScript/simpleAht20test.py", line 6, in <module> sensor = adafruit_ahtx0.AHTx0(i2c) File "/usr/local/lib/python3.9/dist-packages/adafruit_ahtx0.py", line 96, in __init__ if not self.calibrate(): File "/usr/local/lib/python3.9/dist-packages/adafruit_ahtx0.py", line 114, in calibrate i2c.write(self._buf, start=0, end=3) File "/usr/local/lib/python3.9/dist-packages/adafruit_bus_device/i2c_device.py", line 100, in write self.i2c.writeto(self.device_address, buf, start=start, end=end) File "/usr/local/lib/python3.9/dist-packages/busio.py", line 202, in writeto return self._i2c.writeto(address, memoryview(buffer)[start:end], stop=stop) File "/usr/local/lib/python3.9/dist-packages/adafruit_blinka/microcontroller/generic_linux/i2c.py", line 52, in writeto self._i2c_bus.write_bytes(address, buffer[start:end]) File "/usr/local/lib/python3.9/dist-packages/Adafruit_PureIO/smbus.py", line 303, in write_bytes self._device.write(buf) OSError: [Errno 121] Remote I/O error

steady rose
#

could be a timing issue, like not waiting long enough for it to come out of reset

#

so the i2c coms in calibrate() are failing

tight solar
#

Oh I see thanks ! I do see its trying to write out with i2c in line 114, there should not be conflicts between the oled and the sensor if theyre both i2c correct?

steady rose
#

would you be able to edit this file?

/usr/local/lib/python3.9/dist-packages/adafruit_bus_device/i2c_device.py
#

wait. not that one.

#

this one:

/usr/local/lib/python3.9/dist-packages/adafruit_ahtx0.py
tight solar
#

yep yep! its opened with nano currently

steady rose
#

might hit a permissions issue. so may need to sudo.

#

try time.sleep(1)

tight solar
#

Just updated, I will try the samplescript once more

#

No luck unfortunately same result

steady rose
#

the 1 second pause should have been obvious when running the example

tight solar
#

seems like same stack trace as far as I can tell if that helps as well

steady rose
#

just to verify the changes were in

#

like 1 second pause, then stack trace

tight solar
#

Yep it did seem to hold for the second as intended I bumped it up to 5 sec to be certain and it did hold before emitting its error

steady rose
#

hmm...

#

try commenting out the reset

tight solar
#

Cool cool ! Just tried and no luck quite yet. I did also bump the sleep within the class init to 5 seconds though still have the same result thus far

steady rose
#

ok, not sure what's going on.

#

it's something non-obvious with the sensor

#

nothing that you are doing wrong

#

did you buy that AHT20 breakout recently?

zenith crystal
#

what's the I2C baudrate? did you change that in the /boot/config.txt?

steady rose
#

^^ yep, worth checking that (i was assuming default 100k)

zenith crystal
#

every I2C issue i've had on the Pi was due to using the default rate -- it appears that a lot of boards prefer 400k (esp. any Seesaw boards)

tight solar
# steady rose nothing that you are doing wrong

This is reasurring thank you 😅 I was convinced I wasn't writing something in right. Also thanks for the suggestion @zenith crystal as far as I remember I have not edited the boot config file but let me re-verify what is in there to confirm

steady rose
# 
dtparam=i2c_arm_baudrate=
#

^^ it'd be a line like that

zenith crystal
#

dtparam=i2c_arm=on,i2c_arm_baudrate=400000

steady rose
#

if it's not there, then it's 100k

#

^^ or that

#

i2c_arm_baudrate is probably the thing to search for

zenith crystal
#

this is a weird question, but are you running the Pi as a "desktop" (e.g. in graphics mode)?

tight solar
#

I do see the line dtparam=i2c_arm=on in the file though no reference to the baud rate, so I will add in ,i2c_arm_baudrate=400000 to that line and save / reboot and try once more. Also yeah the PI is setup as a desktop could that potentially negatively influence use in this context ?

zenith crystal
#

it might but that's more for getting an idea of your setup

steady rose
#

i'd think anything like that would be more random. this failure is very repeatable.

zenith crystal
#

also, in a terminal type groups and ensure that your user is in the i2c group

#

oh ho! since you mentioned a "3rd party" connector, i ran across something that says This seem to be related to line impedance. pigpiod is periodically probing the pin, which results in additional load on the line.

#

try turning off remote GPIO

tight solar
#

Cool ! I confirmed the user sees i2c when running groups also sounds good, I have turned off all interfaces except SSH and I2C . I have just rebooted and am going to give it another go

tight solar
steady rose
#

do you still have the little plastic bag it came in with the barcode sticker?

tight solar
#

actually yeah haha I usually toss them but its right next to me, would a photo of that help or any info off the sticker ?

#

I do think I tossed the OLED bag

steady rose
#

yes please. just collecting info.

tight solar
#

Definitely!

steady rose
#

thanks!

tight solar
#

Thank you ! I appreciate the time and help with troubleshooting

steady rose
#

my guess is this is some variance in newer AHT20's

#

i'm helping with one other case of this same issue - still on going

#

i can't recreate it locally, but my test AHT20 is a few years old (~2020)

#

i'm going to ask about this internally

#

and will follow up in your forum post

tight solar
#

That sounds good to me, thanks again for the time with helping! If any more info from me would be useful I'm happy to provide it

steady rose
#

np. thanks for all the photos and info.

steady rose
#

@tight solar are you still online? might have something else to try.

tight solar
#

hi yep! still mostly online

steady rose
tight solar
#

ohhh nice thanks! I can check in just a bit. For that change to reflect for me locally I'd need to uninstall and reinstall the library with pip right or would there be any other steps ?

steady rose
#

should work to just update via pip. no need to uninstall.

#

however, may take sometime for release to show up via pip

tight solar
#

I updated the library locally copying that commit info and it worked ! 🥳 I ran the example provided aht20 code from that library and also separately confirmed using both the OLED and the sensor work simultaneously as I originally had wanted. Thank you for the time in getting this resolved !

steady rose
#

awesome! glad that fixed. thanks for testing and confirming.

agile depot
#

Trying to use an SPI TFT and an I2C OLED display at the same time on the FT232H board, and for some reason im getting strange results when I run my code.

steady rose
#

the FT232H can't do SPI and I2C at the same time. only one or the other.

agile depot
#

ohh ok

#

thanks for clarifying

thin pelican
#

so I wanted LXQT on raspbian. I had some trouble with it at first, but i finally got it to boot the desktop environment on startup.

#

now.... none of my core commans work

#

shutdown, reboot, iwconfig, ls, etc and so on.

#

"command not found"

#

only occurs AFTER using raspi-config to make LXQT load on startup

#

any ideas?

zenith crystal
#

it depends on how you're starting the desktop -- open a terminal and run echo $PATH just saw the "load on startup"

you will need to use sudo to execute those commands now -- you're logging in as a "normal" user and don't have root access

broken shuttle
#

There's probably a group that allows you to power cycle without being root, or it can at least be set up in sudoers.

zenith crystal
#

if you use the regular install instructions, the user you set up should already be in /etc/sudoers.d

thin pelican
thin pelican
#

someone suggesting going full raspbian, then changing

#

trying that now

zenith crystal
#

wait -- you can't do any terminal commands?

thin pelican
#

the only terminal command that worked was "echo $PATH" once.. then not a second time lol

zenith crystal
#

yeah, something is really messed up, so starting over sounds simplest (if you have nothing else invested in it)

#

you can always install LXDE after and switch to it at login

thin pelican
#

can i install it, or lxqt, and then remove the original so that ts automatic at startup?

zenith crystal
#

that's a "login manager" option, yes (or should be)

thin pelican
#

basically my end goal is getting something that scales without breaking the hyperpixel4's touch screen. I have it on a pi400 cyberdeck thing, and Ive gotten the project to run fine on raspbian (due to hyperpixels issue with other OS) but using the touch with raspbians horrible scaling, and the fact that i cant fullscreen or split the terminal while working just sucks and really hampers thee tool

#

i use lxqt on laptops and love it, so i figured it would be a good choice.

zenith crystal
#

QT might be a bit heavy for anything other than a Pi 4

#

(i run KDE personally -- but not on a Pi at the moment)

thin pelican
#

id even be happy just having the QTerminal

#

or any other terminal that works on raspbian and splits/fullsceens

zenith crystal
#

by the way "The default desktop manager in Raspbian Is LXDE." is a quote i just ran across

#

Raspberrhy Pi OS comes with PIXEL, which iirc is gnome-based

thin pelican
#

yup

lilac lagoon
#

anybody ever run into an issue when using an arduino based controller on linux? i made a DDR controller and it works just fine on windows but when I try to use it on Ubuntu it is VERY slow. i think maybe it has something to do with the serial port? as the controller is not just acting as a usb controller but also sending serial data over the com ports.

gilded nymph
#

Hello everyone,

I have been working with a robot for a few months that runs on a few Raspberry Pis and uses all kind of motors and sensors like lidar and IMU. I was having some problems with the library that I was using to control the IMU sensor (IMC20948) so I decided to try and use an Adafruit Circuit python library for it.

When I installed Adafruit blinka on my Pi, I realised that while being installed, it was making many changes to the ports, connections and raspi-config which my code uses to control the whole robot. Not surprisingly, I tried running my code after Blinka being installed and I got loads of errors related to the ports so now I'm screwed because nothing works.

Is there any way of uninstalling Adafruit blinka and reversing all the changes made by it on the Pi?
Help would be much appreciated as I am a bit lost and I may loose months of work.

modest dune
#

It seems like the Raspberry Pi 5 was just announced.

zenith crystal
gilded nymph
zenith crystal
#

why disable raspi-config? i don't understand why enabling all the GPIO options would cause other software to stop working, esp if it was using said GPIO options

turbid rivet
gilded nymph
zenith crystal
#

i've got 5 (and counting) Pi's running Blinka and none of them required disabling raspi-config, so i'd undo that

#

how do you "disable" it anyway?

gilded nymph
#

Which makes no sense because I didn't change anything in the code or the hardware

gilded nymph
#

But I couldn't find one to enable it or anything

zenith crystal
gilded nymph
gilded nymph
turbid rivet
gilded nymph
turbid rivet
#

The other possibility I see is the original code was built on an older version of python, and the python updates the Blinka installer performed somehow broke compatibility somewhere?

#

When you get a chance, could you share a clipboard snippet or screenshot of the complete list of errors?

gilded nymph
#

I don't have access to the hardware now but I will send the full snippets tomorrow moning. Thanks a lot for the help guys

zenith crystal
#

ok - did some digging and that's ok -- the idea is that raspi-config runs at first boot for new installs and this just ensures that it does not (which raspi-config itself does)

smoky bramble
#

Im using a banana pi so im guessing this kinda fits here. How do i add a graphical login screen in wayland? Ive never added one in linux (pic is almost unrelated i just wanted to show yall what im doing)

20230928_140707.jpg
zenith crystal
#

login or boot screen? usually the graphical boot is handled via plymouth so that's the starting place for that -- as for a login screen, if you've got a desktop environment installed, you should just change to boot in graphics mode

or i''m totally mis-reading your question 😀

smoky bramble
#

Im not using a desktop enviroment

#

I always download the minimal cli versions of rpi os and armbian and customize it from there

#

Hmmmm but plymouth splash screen, never thought of that

#

Looked it up, i need to use a login manager

#

@zenith crystal

#

So im guessing the order is boot -> plymouth splash -> login manager -> window manager

zenith crystal
#

that is correct

smoky bramble
#

Also, i dont use arch btw 😏

zenith crystal
#

i wouldn't have accused anyone of that 😈

unique tulip
#

I guess that means that you aren't each others arch rivals.

velvet rampart
#

Is arch Linux the official distro for aarch64 processors?

broken shuttle
#

No.

#

In fact Arch Linux doesn't officially support ARM, but the archlinuxarm project provides ARM binaries.

velvet rampart
#

I see. Wonder why arch name seems so popular now

broken shuttle
#

Arch is a minimalist distribution and highly configurable.

velvet rampart
#

Perfect words for selling a distro ngl

broken shuttle
#

btw I use arch

#

It's been my main os for the last... 8 years or so.

velvet rampart
#

Yeh I might join you some time

#

I've been using Debian a lot, fo some reason I declined arch Linux even though I did try manjaro

#

I'm at a base place of figuring out my personal computing needs so anything is available again which is cool

#

Minus apple.

#

That's just a no

broken shuttle
#

Personally... I'm not entirely sure why manjaro even exists. It uses Arch tooling but is incompatible.

#

I can solidly recommend AMD for the CPU and GPU.

velvet rampart
#

Yeh I've got a ryzen

wraith grove
#

I've been wary of AMD graphics since the ATI days, maybe I'm too grudgy?

dusk flower
hard pike
upper ice
#

Has anyone had issues with importing bitmaptools? I'm trying to use the scrolling label function on an 8x8 LED matrix (jetson nano) but it requires bitmaptools.

olive haven
upper ice
olive haven
tawdry ledge
#

Hello all, i am having great difficulty getting NeoPixel to run on my Pi4, anyone have experience?
I have done the following:
Added pi user to sudo, gpio, spi, i2c groups

'sudo pip3 install rpi_ws281x adafruit-circuitpython-neopixel'

created python script in '/home/pi/documents/neopixtest.py'

trying to run in terminal: 'import board'
error: module no exist

trying to run in thonny:
"Can't open /dev/mem:perm denied"

Also yells at me at the bottom i need sudo perms.

Anyone have any idea's please let me know thanks in advance

dusk flower
#

Did you do logout and login again after adding user to the groups?

tawdry ledge
zenith crystal
#

after adding the user to the groups, you need to sign out and back in again, then you need to install blinka -- that's what has the board stuff in it

#

well, as a dependency actually 😏

wise bone
#

Hey, I was wondering if anyone could point me in the right direction for using BLE on Pi Zero W. I'm pretty new to this and can't find any examples that help.

waxen bane
#

can someone help with a servo issue

#

i have installed all over the proper libraries and have all the nessessary equiptment but idk why the servo wont move

#

if anyone could help it would be much appreciated

umbral sable
waxen bane
#

i have a raspberry pi and its own power 9v power sorce

umbral sable
waxen bane
#

no its a wall wart

umbral sable
waxen bane
#

yes i have

umbral sable
#

Cool. Does the servo wiggle a bit or home itself if you move it out of position when powered up?

waxen bane
#

no theres not movement what so ever

umbral sable
#

Hmmm, that's a little concerning but not 100% a problem since some servos would wait to receive a control signal before moving.

#

Are you using just basic example code to try driving it, or something custom you've written?

waxen bane
#

a basic example but now i am getting a new error

# 
import time
import board
import pwmio
from adafruit_motor import servo

# create a PWMOut object on Pin A2.
pwm = pwmio.PWMOut(board.A2, duty_cycle=2 ** 15, frequency=50)

# Create a servo object, my_servo.
my_servo = servo.Servo(pwm)

while True:
    for angle in range(0, 180, 5):  # 0 - 180 degrees, 5 degrees at a time.
        my_servo.angle = angle
        time.sleep(0.05)
    for angle in range(180, 0, -5): # 180 - 0 degrees, 5 degrees at a time.
        my_servo.angle = angle
        time.sleep(0.05)```
#

wouldnt let me copy from rdp for some reason

umbral sable
#

Possibly you're using Arduino example code instead of RasPi?

#

I'm not sure offhand which pins would be PWM-capable.

rotund pivot
#

@waxen bane dir(board) will list the available pin aliases

waxen bane
#

ill give it a try

waxen bane
#

idk what this means

rotund pivot
#

you've switched paradigms, that looks more like RPi.GPIO library than CircuitPython with Blinka

#

do you have a line like import RPi.GPIO as GPIO?

#

of so, instead of pin.id, try putting just the pin number, like:```py
import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BOARD)
GPIO.setup(11, GPIO.OUT)
GPIO.output(11, 1)

waxen bane
rotund pivot
#

Back up... you've posted code from two different Raspberry Pi environments: CircuitPython with Blinka, and Python running under Raspbian. Which are you trying to use?

#

If you want to use CircuitPython libraries (like adafruit_motor), you'll want the former, and the RPi.GPIO stuff is irrelevant

waxen bane
#

when u say enviorment do u mean operating system?

rotund pivot
#

different sets of Python libraries essentially (maybe they could co-exist, but it would get really confusing )

waxen bane
#

well i have both of them installed lol

rotund pivot
#

Blinka, and RPi.GPIO?

waxen bane
#

yeah

rotund pivot
#

that's fine, they can both be installed, but depending on what you are trying to do, one may be a better choice

waxen bane
#

ive tryied using scrips with both and neither of them have worked

rotund pivot
#

try one or the other

waxen bane
#

but i think i might have fried my gpio pins

rotund pivot
#

what makes you think so?

waxen bane
#

i tried seeing what i2c adress it was at but nothing was showing up and now i have a script that has the servo plugged into the pi but its not working

rotund pivot
#

do you have this on a breadboard, or headers and jumper wires, or...?