How to connect a NB-IOT unit to M5GoBottom (Core2)

falbriard

For M5GO BOTTOM2 component and available port B what is the UART interface numbering for RX and TX signals?
Want to connect an NB-IOT unit via an UART cable. I've already allocated pin 13 and 14 for the GPS unit in the stack.

felmue

Hello @falbriard

you'll find your answer looking at the published pin-mapping.

Thanks
Felix

falbriard

The H5Go Bottom module implements "HY2.0-4P-PortC(blue)" and by default points to GPIO13 (RXD2) and GPIO14(TXD2). The same pins are already in use by the GPS module part of the M5 Core2 stack (currently set to TX=14, RX=13). Is there a solution to operate both modules in parallel, the NB-IOT (Uart) unit and GPS module?

felmue

Hello @falbriard

yes, port C (blue / GPIO13 / GPIO14) is blocked by the GPS module. However you can define a second serial connection in your code using port B (black / GPIO26 / GPIO36) and then connect the NB-IOT to port B.

And no, using two UART (serial) modules in parallel on the same port is not possible.

Thanks
Felix