Collision on UART RTS and SPI CS pin - will there be any issues?

Silly question on some low level functionality - I got some new prototype boards made because we are putting the ATWINC wifi modules in one of our products. I cannot, however, for the life of me get the chip to Enable properly. Pinouts have been triple checked, the module has the proper firmware (19.6.1), but it always throws an Invalid Operation exception ( CLR_E_INVALID_OPERATION (1)) when I try to enable the module. upon further inspection, the chip select we are using for SPI5 is UART7’s RTS pin. The pin opens fine and seems to be working ok, and the RTS functionality on UART7 is disabled according to the IsRequesttoSendEnabled property, but would this cause issues under the hood anyway? it’s the only thing I can find.

try same code, only change pins (and SPI) make sure it works on Dev board.

And SPI, depend on wire length, recommend <= 4MHz.

And there is no IsRequesttoSendEnabled, only “Handshaking” or “EnableDePin” effect to RTS pin. make sure they are not used.

ordered a breakout board to wire the wifi into the dev board - should be here in a couple days.

I think we should have a click board then no need wire.

We are testing software so make sure the connection is good.

Mikro is easy, but I want to be able to move pin assignments around if necessary. chances are this will necessitate a revision update on the board and I want to make sure that the software is solid and pin assignments are set in stone before that happens. this particular instrument is using well over half of the available GPIO (it’s extremely complicated) so pin collisions are a concern.

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