Hi, I have designed a custom board that integrates the ATGM336H-5N31 GNSS module. I am trying to talk to the chip with I2C, but my microcontroller can't find the chip (it can find my I2C accelerometer). I was wondering if someone maybe has some experience with the I2C on this chip, because I only s…

If You post the schematics of Your build it would surely help a lot.

What is out there is that this module can do UART/I2C/SPI. However no mention about I2C address! Uart will definitely work, but if you wanna try I2C anyway, take a look at this: https://playground.arduino.cc/Main/I2cScanner/

I have uploaded an I2C scanner to my board, and it unfortunately can't find the chip, it can find my IMU connected to the same lines though.

[image] Railroader: If You post the schematics And so you did, partially. We need to see everything of the SDA SDL lines.

My schematic is quite big, but I will post everything then :slight_smile:

[image] gwoonryan: I have added them Thanks! Sadly I don't manage to magnify it to a readable format. Hopefully other helpers will benefit from it.

[image] Railroader: Sadly I don't manage to magnify it to a readable format. It's in .svg so no wonder. But Gimp could open it here, and the pullups are a bit restrictive, 10k. Experiment with something around 5k. Also what speed do you use?

If you want to still help, you can right-click the image and open in new tab to enlarge it :slight_smile:

I have not specified a speed in wire.h, do you think this matters for discovery of devices? If so, I will try with 5k pull-ups. (I can only check this in a few days probably though). And do you think that the connection to ground from the ON/OFF pin is correct? Or do you think it has to be tied to …

I2C on the ATGM336H-5N31 GPS module

Projects General Guidance

srnet January 9, 2025, 9:47pm 15

Ublox GPSs can use I2C connections.

The address is 0x42.

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I2C on the ATGM336H-5N31 GPS module

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