Rak811 Tracker Board


HDOP: Almost, but this gives you a range of -12.9 - 12.8. Rather go with unsigned ints to get a range of 0 - 25.6 because hdop will always be positive.

Altitude: Why do you need centimetre accuracy, while the altitude accuracy you get from the GPS is in the order of 10’s of metres. Better to stick to metre resolution to save space.

Lat: You multiply by 10000, so you end up with a value in the range -900’000 - 900’000. You then store it in a 32bit int, which has a range of -2’147’483’647 - 2’147’483’648. You are therefore wasting (4’294’967’296 - 900’000 - 900’000 / 4’294’967’296 = 99.958%!

Rather use the format as suggested by @RussNelson, which can be found on github. This format was designed to not waste a single bit, therefore maximising the resolution and minimising the LoRa time on air.

(Jcaridadhdez) #254

I was wondering about the reason of choice one or the other format, (@RussNelson suggested to use yours) , thank you for the explain, it saves me a couple of hours.
I will use your format as soon as I get some free time
My purpose was just to give OlofAst another way to test.

(Russ Nelson) #255

Hmmmm… I think I need a better antenna. I missed out on a bunch of places that I know have good reception. And/or increase the rate of transmission.


(QLion) #256


How would you go about connecting, a sensor to the trackerboard.

is there 2 gpio pins that i can use?

(Musti) #257

I have operational devices with https://github.com/jcaridadhdez/RAK811-tracker code, programming has been slightly tricky, but on Ubuntu the following works for me:

sudo apt-get install stm32flasher


pio run

<move BOOT jumper on RAK811 board, plug in usb>

stm32flash /dev/ttyUSB0 -j
stm32flash /dev/ttyUSB0 -k
stm32flash /dev/ttyUSB0 -e 0 -w .pioenvs/rak811/firmware.bin

<if any of the above commands fail, unplug and plug back in until it works>

(Russ Nelson) #258

Without a doubt. What kind of device do you want to connect?

(QLion) #259

Hi Russ

I’m trying to connect a ultrasonic sensor, I think I got vcc and ground, but just need 2 pins for trig and echo.

will the following pins work?

pinMode(PA1,OUTPUT);  // Physical pin PA1 on the board ?
pinMode(PA15,INPUT); / Physical pin PA15 on the board ?
digitalWrite(PA1,LOW); // Pin PA1 |   LOW is off / HIGH is on ?
digitalWrite(PA15,LOW); // Pin PA51



(Russ Nelson) #260

All these pins are brought out to the 10 pin headers on one side or the other.
All are GPIO.
All are 5V tolerant.
PB12 and PA1 are also ADC inputs

PB12 1 available
PA8 4 available
PB3 8 available
PB5 9 available
PB2 6 available
PA1 7 available

PA15 is used to control power to the GPS.

(QLion) #261

Thanks for the info…

(Olof Ast) #262

Has anyone tried RAK811 on mbed?
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.


(Russ Nelson) #263

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!


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/


2 posts were merged into an existing topic: RAK811-Trackerboard with mbed & Arduino frameworks

(Jezd) #266

are you able to share your code?

(Olof Ast) #268

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.

(Goran Mahovlic) #269

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 :frowning:


(Jac Kersing) #270

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)?

(Goran Mahovlic) #271

Yes missed no. it is 811 :slight_smile:
Moved to 811 https://github.com/goran-mahovlic/RAK811-GPS-FORWARDER

(Russ Nelson) #272

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.

(Vladimir Bakum) #273

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.