Meshtastic

Connect GPS module to Lora32 V2.1

Hello colleagues!
I have in use 2 modules TTGO Lora 32 V2.1 and I have a separate GPS module NEO-6. I want to do an experiment. In this regard, there are questions:

  1. Can I connect NEO-6 to Lora32 V2.1 module?
  2. Is there support for GPS modules in the Lora32 V2.1 firmware?
  3. Maybe it is possible to activate the GPS-modules with some kind of meshtastic-commands?
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Hi,
You can connect the gps on the lora32, but the default lora32 firmware don’t have it enable.

You can modify the firmware on platform.io and add the definition for the gps pin.

Thanks, I understand, we will deal with the source codes.

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If you don’t mind, please share what you find or write in the code. I had the excact same question as you.

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Unfortunately, I’m not a programmer at all and I have to look for coders from friends. I hope there is someone who can deeply understand the code and help me with something. If the result is positive, then I will definitely share it.

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If you want i can try to build the firmware whit the gps. You only need to connect the gps on tx/gpio01 and rx/gpio3.

I hope to bee able to do it as soon as possible.

Also @geeksville can be done something to enable the gps via the python api or the app on some predefine pin?

The GPS support needs to be included at build time, so alas the python tool can’t do it. However, for all ESP32 targets (unless the target has been customized for a different pin) have the GPS enabled on the following pins:

gpio 34 gps_rx (i.e. data from the gps towards the main CPU)
gpio 12 gps_tx (i.e. data from the main CPU towards the GPS)

If you use these pins you don’t need to build any code at all. And both pins look unused on the lora board you mentioned,

At a minimum you need to hook up power, ground and gps_rx. gps_tx is optional but recommended.

But all of these behaviors are controlled by src/configuration.h. In this case see line 108.

Does that help?

Its plug and play so to speak. I know I had the same questions not to long ago… its not pretty but it works

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Hello colleagues.
I can try the experiment, but this requires someone to make a binary firmware.

The standard binaries already support this. No need to rebuild.

IO 12 is already used for the paging button. It is correct?

I did testing:

  1. I downloaded firmware 1.2.11 alpha to my T3_V1.6 module
  2. I connected the GPS to the module along three lines (+V, GND and TX (data from GPS to the module, pin IO34))

But the screen also shows No GPS. (At the same time, the module shows with an LED that the satellites have been found and the coordinates have been fixed.)

Someone, tell me where the error is?
Thank’s.

hmm - what was the exact filename that you installed onto the module? I’ll check that against these lines

I have installed the firmware “firmware-tlora-v2-1-1.6-1.2.11”.

In this piece of code, I seem to see an error:

#define HW_VENDOR HardwareModel_TLORA_V2_1_1p6

#undef GPS_RX_PIN
#undef GPS_TX_PIN
#define GPS_RX_PIN 36
#define GPS_TX_PIN 13

If this is the code for ESP32 pico d4, which is in the T3_1.6 module, then IO36 is not in it. For the convenience of connection, it would probably be convenient to use IO_15 and IO_13, since on the board, these pins are next to each other.

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For example, maybe it would be convenient to connect like this. IO_13 and IO_15 or IO_34 and IO_35. Perhaps even crossed. The main thing is that there would be pins nearby.

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Or, quite an ideal option for all the pins to be on the same side (IO_26 busy under DIO_0 for LORA):

ok sounds good! that change will be in the next release and also in @mc-hamster’s automated nightly build tonight (california time):

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Kevin, thanks a lot for editing the code.
Checked the work of the GPS. Everything works well. I see my position on the T3_V1.6 board!
I only used the TX line on pin IO15 (RX for the CPU and TX for the GPS module) and it worked.

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A friendly reminder to always have an antenna attached or the lora radio may die.

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Yes, you say everything correctly! I wanted to check the gps very quickly, I forgot to connect the antenna. :upside_down_face:
Don’t forget to connect the radio antennas to the board!

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