#Low power temperature reader with RF
severe gate
young oracle
So Ive found better modules to use other than those RF modules
If you dont mind waiting a bit from LCSC, they are pretty inexpensive.
check out this list of the modules I tested
When I tested them in much of the same environment, they did pretty well in the house. I would make your own RF packet though, since you want multiple address's
Ive found some other ones on Aliexpress too, they are mostly the same
made by this company called "Feng RF"
severe gate
Thanks! Can't open this on my phone, so I'll have a look tomorrow :)
With own RF packet you mean the packet that is sent from the transmitter to the receiver?
young oracle
yes
severe gate
And what makes the RF modules that you found better? If it's explained in the ods file, then no need to explain :)
young oracle
basically in the arduino you would say
(pseudo code)
UART.WRITE: Preamble
UART.WRITE: Preambe
UART.WRITE: Address byte
UART.WRITE: Payload1
UART.WRITE: Payload2
UART.WRITE: Maybe check sum
UART.WRITE: End
young oracle
And what makes the RF modules that you found better? If it's explained in the od...
I dont have RF equipment to give a quantitative measure, but Ive found that the signal tended to be "clearer" and not have a lot of junk on the UART side of things.
They are also more modern in a sense that they seem to use more modern IC's rather than two transistors and a crystal.
so thats a receiver for example. Built in antenna. Small
severe gate
Thanks a lot!
young oracle
np
severe gate
Do you have any inputs regarding using the arduino pro mini as microcontroller for this, when I want it to be low power?
young oracle
That board I think is fine. It doesnt have the FTDI circuits to take away power and it looks like it only has a regulator on it. You should be good on a small battery.
But it also depends on how long you want it to last. Months, years? etc. A single 18650 will last a while, even two AA batteries will be OK (but thats 3V, you might need another battery or boost converter)
For a beginner project like this, its fine.
Thing is, you wont know how much current it will consume until you do IRL testing.
severe gate
Weeks would be okay, ideally months
I'm planning on a 3.3V Arduino, so technically 2 AA batteries should be fine?
But also, I was planning on using a button cell as battery. Would that be something that could provide enough power for such a long time?
young oracle
The sleep command works wonders, and you'll have to make use of interrupts.
severe gate
Thing is, you wont know how much current it will consume until you do IRL testin...
I figured as much already but also thought that someone might have more insights on this
young oracle
I figured as much already but also thought that someone might have more insights...
https://www.arrow.com/en/research-and-events/articles/getting-started-with-the-arduino-pro-mini
https://forum.arduino.cc/t/power-consumption-of-arduino-pro-mini-and-arduino-pro-micro/887145
1.6mA is still a fair amount. This will be OK to get things running as a starter project.
But if you want to get more into it: you'll have to read up on the interrupts, sleep, and using a timer to wake the micro up once and a while to do things
severe gate
Sweet, thank you!
I wanted to get an initial opinion if what I'm trying to do is even feasible or if it's doomed from the start, no matter how much I try to optimize it code wise (for example if I wanted to power an uno with a button cell)
This helped a lot already, thanks again!
young oracle
Its feasible. You can probably power it from a button cell, but it depends for how long. If you want ultra long power, you would have to probably ditch that whole assembly, grab an ATmega and roll your own circuit
severe gate
I think the ATmega approach is something that I could tackle once I have more experience, but good to know!