Communication between pca10040 and another device using UART

[lirank]

Hello,

I would like to establish communication between my pca10040 and my cellular modem. Currently I am using ble_app_uart on the peripheral example and I can put messages and get messages via UART manually (opening tera term with pca10040's COM port and sending \ receiving messages via BLE). Is there a way to forward the COM port or UART interface of pca10040 to the COM port of the cellular modem?

Thanks in advance

[endnode]

Can you elaborate more about where is the radio and which devices are connected with wired UART? Or is your question about support of Nordic BLE UART service (NUS) on your modem?

[lirank]

Currently I am connecting both pca10040 and my cellular modem with wired UART (each to a different COM port) and I would like for them to be on the same port (or physically connect them so that I can send a command to the pca10040 and it will forward it to the modem's COM (via UART). I hope that is clear enough

[endnode]

Not really;) Are you connecting both things to COM ports of some 3rd device or you connect UART from PCA10040 (there is no COM port;) to some serial input/output port of the modem?:) If you want to connect them directly then obviously your "modem" must have the same electrical properties when it comes to serial (UART) line and you need to then execute some agreed logic on top of it from both FWs (who will talk when, what baud rate and coding will be used, what protocol to interpret byte stream etc.) But that's always the same with UART, doesn't matter if it's Nordic nRF5x chip, Arduino, PC with native serial port or some FTDI RS232-3V3TTL convertor...

[lirank]

OK so I think I can narrow down my question: Right now both are connected to a computer. Is there a way to make a UART connection directly out of the pca10040? If so, do you know which pins are to be configured? And how to configure them?

Thanks

[endnode]

OK, this looks like a question finally;)

Yes, nRF52 can do bi-directional full-duplex asynchronous UART communication with or without HW flow control and with or without parity at various baud rates up to 1Mbps. It can be assigned to pretty much any of 32 GPIO pins (until they have proper HW layout on the board outside nRF5x chip) by SW, this is standard property of all nRF5x chips. Overall you should definitely read the specification on Infocenter. So yes, anything which is electrically compatible to this specification can be connected to nRF52 and configured in the FW. And that's pretty much all we can suggest until you tell us something more about the counter part (mysterious "cellular modem";)