What do I need to make the I²C on a fresh L76-L work?
We used a Quectel L76-L for a prototype. The I²C will not work however. The UART always send me GPS coordinates every second but somehow the I²C does not respond or even screws up the I²C bus making other devices unreachable.
Any ideas? Do the I²C need a init via UART first or something? Or is not standard in I²C slave mode? I'm all out of ideas.
I tried removing the I²C pull ups and I tried switching the GPS chip.
Meanwhile I can confirm you are right. It turns out the I²C only works with the latest FW version. And the modules are shipped with an older version.
It turns out you need to ask the importer (not Quectel itself) about this. They are going to provide a link with download for FW and upgrade tool since it is not available on the Quectel website.
Thanks for the tip about the FW version!
@Thosch42 Thats actually a very good tip. Any idea where to download the firmware and upgrade tool? All I found was the document Quectel_GNSS_FOTA_User_Guide_V1.0 but it does not provide any info on where to download the updated firmware versions. How do you perform your update?
Thanks a lot!
@robert-hh We noticed and connected the right pins. But as soon as the GPS is placed, the whole I²C bus is unusable. Also the other devices on the bus are not reachable anymore.
Thosch42 last edited by
@Vincent Possibly your L76 has the wrong firmware. I use a L96 in some of my projects, and I need to update the firmware on every device.
robert-hh last edited by
@Vincent I found this data sheet: https://www.quectel.com/UploadImage/Downlad/Quectel_L76_Series_Hardware_Design_V3.1.pdf
So it looks like I2C is on different pins of the chip.