LimeNet Micro: GNSS TPULSE into the CM3

I need the GNSS timing pulse connected to the CPU on the CM3 of my LimeNET Micro. Its only wired to the FPGA as shipped.

Is there any reason why adding a mod wire to GPIO28 on the CM3 wont work?


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I made some modifications to the FPGA gateware for this. It is trivial and should work fine. You just need to add one more signal in the top entity and connect it to the RAPI_GPIO12 output port, the GNSS_TPULSE input port and the internal gnss_tpulse of the inst7_limegnss_gpio_top entity

With this I can see the pin changing status on the Pi and it is detected by pps-tools if you provide the correct overlay in the usercfg.txt file

I am using Ubuntu server 20.04 on the CM3