Rak811 Tracker Board

[OlofAst]

Has anyone tried RAK811 on mbed?
https://os.mbed.com/
In MBED release 5.8.2 RAK811 support was added.
But maybe that is for a separate thread, will add one when I have time to look at this.

https://os.mbed.com/teams/Semtech/code/LoRaWAN-NAMote72-Application-Demo/

[RussNelson]

Anybody tried using the board without an external active GPS antenna? I did, and got no GPS fix at all.

My goal for today is to design a 3D printed case for the tracker, holding an 18650 battery and the tracker together. I dropped my tracker and bent the antenna’s SMA connector. Gotta protect the poor thing if I’m going out and about with it!

[nicbkw]

Hi @OlofAst, I tried the original RAK811 board (no GPS) and needed to post a question on the mbed forum - https://os.mbed.com/questions/81016/LoRaWAN-support-for-MTB_RAK811-target-in/

[jezd (JD)]

are you able to share your code?

[OlofAst]

Not sure if I am doing this right but for those interested in development for the RAK811-Trackerboard with mbed os arduino, please look here.

RAK811-Trackerboard with mbed & Arduino frameworks

The RAK811 Trackerboard thread i getting quite big. If you want to add hardware you might want to consider using the Arduino or mbed frameworks. This guy is working on an Arduino port, https://github.com/stm32duino/Arduino_Core_STM32 Also some people are looking at the mbed framework that recently has added support for the RAK811 board. However using the mbed framework with OS fills the entire flash and not the basic support for the gps and sensor. I would like to get the people interested…

[mistery (Goran Mahovlic)]

goran-mahovlic/RAK811-GPS-FORWARDER

I have created code to bridge GPS serial and USB serial.
Idea is to set GPS to low power mode to send data only every few minutes not every sec.
GPS > USB is working nicely
I still do not know how GPS config message ends so I send byte by byte.
I do not see any change when I send config to GPS

[kersing (Jac Kersing)]

Rak831? The lorawan gateway module? Why would you want to set the gps to low power for a gateway?
Or did you make a mistake in the numbers and are you referring to the rak811 (the subject of this thread)?

[mistery (Goran Mahovlic)]

@kersing

gateway

Yes missed no. it is 811
Moved to 811 GitHub - goran-mahovlic/RAK811-GPS-FORWARDER
Tnx

[RussNelson]

Progress. I have a 3D printed part that holds the battery and board together reasonably securely.
I have figured out how to talk to the software over the serial port.
My thought is to use one of the GPIO pins to put it into serializing mode.
That would let you enter the id and key of your application.
It will be stored in the EEPROM, along with other things like the delay between transmissions, and whether you wanted to upload the accelerometer data and/or battery data.
That, plus an integration with ttnmapper would let you do mapping without having to compile any code.
I could make binaries for any of the regions. That could probably also be turned into a run-time selection, but it would also make the code larger. I haven’t checked to see how close we are to filling up the code space.

[rsoft (Vladimir Bakum)]

@rchaudet

Also, current source code doesnt allow you to reach low power mode: it checks for power supply type and is coded to always be “USB_POWER” (in timer.c TImerLowPowerHandler() ). just remove this condition or define “BATTERY_POWER” in GetBoardPowerSource(). Once you have done that, low power will work but LoRa connectivity won’t, because the board is put in deep sleep straight after starting joining process. What I did is replacing DeviceState = DEVICE_STATE_SLEEP after printf(“OTAA Join Start… \r\n”) by another state I added in enum eDeviceState: DEVICE_STATE_WAITCONFIRM. Sleep mode works properly, MCU consumes almost nothing but since others components like GPS are always ON despite of that, the board will still consume more than 20 mA in best cases.

I dont use GPS module (not soldered).
I removed power LED, software disabled LED1 & LED2. Now current consumption of board is:
Hold the RESET button - 39.5 mA;
Wait mode - 6.5 mA;
Transmit of packet - 68.8 mA;
Two short strange consumption after transmit - 22.2 mA.
Now drop of voltage is 70 mV per one day (18650). I would very much like to get values in microamperes in sleep mode.

I did as you wrote, but I can not put the device into sleep mode.
Are you able to share your code? Or working example, please.

With best regards.

[RussNelson]

Hrm. Does this CPU have any non-volatile storage in it?

[OlofAst]

I think it has eeprom starting at 0x08080000.
With mbed you can access it like this.

#include “mbed.h”
#include “stm32l1xx_flash.h”

FLASH_Status writeEEPROMByte(uint32_t address, uint8_t data) {
FLASH_Status status = FLASH_COMPLETE;
address = address + 0x08080000;
DATA_EEPROM_Unlock(); //Unprotect the EEPROM to allow writing
status = DATA_EEPROM_ProgramByte(address, data);
DATA_EEPROM_Lock(); // Reprotect the EEPROM
return status;
}

uint8_t readEEPROMByte(uint32_t address) {
uint8_t tmp = 0;
address = address + 0x08080000;
tmp = (__IO uint32_t)address;

return tmp;

}

Should be similar with cmsis,
#include “stm32l1xx_hal.h”

[kenyu]

correct, any question send email to ken.yu@rakwireless.com for coordinate.

[RussNelson]

Should I expect this to work with the Tracker? https://www.aliexpress.com/item/STOTON-high-gain-SMA-connector-28dB-BEI-DOU-GPS-Antenna-Ceramic-Patch-Built-in-GPS-Active/32816386209.html?spm=a2g0s.9042311.0.0.3da24c4dFq5qNG

It seems not to work.

[Olunia]

This one works:

Look what I found on AliExpress
http://s.aliexpress.com/ZbiYBfYv

[kenyu]

After seriously read the discussion by this thread and rak forum, we collect the suggestion and decide to optimize the rak811 tracker design as following:

1. The R1/C1 pin of GPS power switch chip U5 needs to be connected to a pull-up circuit。
2. Power indicator LED1 light removed. Reserve charge indicator, and two GPIO control status indicators.
3. The EXTINT0 and ANTON pin of the GPS module needs to be connected to GPIO to facilitate wake-up in low power mode.
4. CP2102 chip removed, add a serial adapter board accessories。
5. Add GPIO to detect the power supply type of the device, battery-powered or USB-powered. It can be detected using the power chip PG pin and CHG pin.
6. Directs one UART interface for users to expand to other devices。

Any more suggestions to RAK Wireless?

[quintin5010 (QLion)]

Arduino Compatible ?

Thanks Kenuy!!

[RussNelson]

Yes, that does work. I have one already. I’m looking for something with a shorter cable, so it’s not so bulky.

[RoJa]

Hello, have you test with an another antenna ? I search an small active/passive antenna compatible RAK811 Tracker but I read about chip MAX-7Q is only with passive antenna. I’m not sure. I find only antenna with a long cable.