Arduino core for CMWX1ZZABZ-078-based LoRaWAN devices

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28

Connection to what exactly?

29

Does it work on AT Command too? which pins are of UART (PA2 & PA3) or( PA14 &PA13)

30

need to use USB to UART adaptor to access it . which pin are for UART?

31

Please see the Tindie product page where a lot of these basic questions are answered and there is a pin map.

But simply, the Grasshopper is designed to be programmed via USB using the Arduino IDE. No external programmer is needed, but you can also use an ST Link V2 to program via the SWD port.

You can load ST/Murata firmware that allows AT command usage, but I have never done this.

32

do these murata module directly by default work on AT command or do we need to program ?.

33

You need to load the firmware provided by Murata that enables AT commands.

34

@onehorse
Hello. I want to ask you a question.Why Grasshopper LoRa / LoRaWAN Development Board with pin number 48 45 and 47 46 short circuit?

35

We want to control the TCXO directly.

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36

I using the development kit B-L072Z-LRWAN1 but there is 2.78mA current consumption in stop mode.I measured vdd_mcu_lra

37

The ST dev kits aren’t designed for ultra low power. You probably still have USB enabled as well as the TXCO, etc. Probably not really able to enter STOP mode at all with that board.

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38

I will check the software again vdd_mcu_lora ~ 11mA, in stop mode I could not drop below 2.7mA.I’m closing debug, trace, printf.The pcb I designed for testing gives the same values.

39

If in your custom design you followed the Grasshopper design and used a CMWX1ZZABZ-078 and are using the Arduino core and Grasshopper board variant then I would expect you would see the same ~2 uA we see in STOP mode.

However, if the module (i.e., CMWX1ZZABZ-072) or pin map is different then I would not expect using the core with the Grasshopper board variant would produce this result.

The B-L072Z-LRWAN1 board design and Arduino board variant are unlikely to produce this result since, as I mentioned, it was not designed for ultra-low power. In fact, certain hardware choices preclude it in this design.

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40

I would like to explain the hardware. I used the LD39050PU33R regulator. I disabled the GPS connections and the existing LEDs as an extra hardware.I’m using cmwx1zzabz-078 and I see 2.7mA in stop mode from pin 5.As a software, I program the software provided by ST on Cubeide. Thank you for helping, I’ll share the results here

41

I program the software provided by ST on Cubeide.

Yup, this is likely one of the problems…

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42

How should I go about it?

43

Surest way is to redesign your custom board to conform to the Grasshopper design and use the grasshopper Arduino core. The ST CubeMX software is not design for ultra-low power, ironically enough.

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44

Thank you for helping.There must be a solution, I will try

45

I have some code that works, but I have to press the “RST” button on the board every time for it to work properly. (to start transmitting data). Is there a way to do this in the code as a startup procedure? Or is there some other issue I need to address?
Thanks

46

Which hardware are you using? If this is a Grasshopper pressing the reset shouldn’t be necessary for LoRaWAN Tx; I don’t even understand how this could work. If you are using the Grasshopper Arduino core you could try STM32L0.reset(); or something like this (check the core for the exact syntax).

47

Its the Grasshopper board, but yeah not sure why this works, just tried it on a whim. I will have to try out your suggestion, will check the core for syntax. Thanks