I’m on a project with P2P between two RAK812 that work perfectly on Arduino Uno. Now, i want to use Arduino Pro Mini in 3,3V to reduce power consumption, but i’m not able to communicate with the RAK812 module anymore ! Nothing. I guess i have to bypass the 5V to 3,3V UART converter, but i don’t don’t where i have to put my RX-TX signal …
The version of RAK812 is ancient and RAKwisnode has achieved low power consumption up to 9.7 μA. You can email us and send a WisNode for testing to you.
I know RAK812 are obsolete, but I only have them for the moment to achieve my proof of concept ! In the futur, I will buy RAK811 of course.
The power consumption of the RAK812 is very low, but the power consumption of Arduino Uno is not (like 45mA !!) ! That’s why i use a 3,3V Arduino Pro Mini (less than 1mA).
So can you tell me if it’s possible to communicate with a RAK812 by the UART but in 3,3V instead of 5V ?
(sorry if I made mistakes in my sentences, etc, i’m french )
Just a last question, maybe not on the same subject but whatever ! Is it possible to communicate between RAK811 and RAK812 on P2P ? I guess yes, but just to be sure !
As I told you, for the moment I’m doing a proof of concept in the company where i work, but in the futur, we will make an entiere PCB dedicated to our connected objet, and we will certainly use RAK811.
I still have troubles… but this time … very weird troubles ! I pass trought the TXD and RXD pins, and I can send AT commands to the RAK and it works, but the RAK doesn’t answers to my Arduino ! This is incredible… like, it’s just 2 wires, and i have troubles !
I know that AT commands works because I can send message and data, and receive them perfectly with another RAK module which is connected to my computer.
So … Why the TX Arduino to RXD RAK works, and TXD RAK to RX Arduino doesn’t works ?
Do you have something to help me ?
It may well be that the Arduino is struggling with a fast baud rate. Due to clocking errrors/drift, 115200baud is too fast for an Arduino - so you could use a serial adapter to change the baud rate of the RAK module to something slower - I use 9600 but I hear that up to 57600 is OK.
When i saw yours answers I was so happy !
But now… go back to reality ! I’m trying to set the bauderate at 9600 ! But impossible, no success … even with RAK Serial Port Tool.
I send “at+uart=9600,8,0,0,0” ( /r/n is no needed) and it give me “ERROR-1”
I tried many times with arduino and now with Rak Serial Port Tool, but nothing i’m stuck. I always use RAK811 datasheet to know AT commands, but I have RAK812… Is there something different between the two RAK ?
Sorry for asking you more help, but i’m still stuck !
As mentioned before, this version is old, I suggest you replace RAK811, so that we can help you better!
PS:If you do not need /r/n, you need to change other serial port tools to send try.