Have you also wondered how to get serial IO (UART) with nRF51422-EK via the Segger debug interface?
[list=1] []Plug Eval kit in the USB port. []In Windows open "device manager" and read the port number from "Ports (COM & LPT)" under "JLInk CDC UART Port (COM16)". My system uses COM16 but this could be different in other setups. []Open a serial port terminal program or similar application on the PC and set the proper port nr, baud-rate, RTS/CTS, bits and parity which match the values in the target. (default in examples is 38400 baud, no RTS/CTS, no parity, 8bits). []Run the Target application on nRF51422-EK.
[/list] Note that the printf(), puts() functions are discarding return values from underlying uart I/O call's, so back-pressure is not working even if RTS/CTS is enabled. This can show up as garbled-up data. To avoid this, use the functions from the underlying app_uart.c and act according to the return values.
As I understand, it is possible with app_uart.c to have the nRF51x22 to power down and sleep-wait when CTS back pressure is signalling that the host is busy and can take no more data. I did not get this to work however. Setting APP_UART_FLOW_CONTROL_LOW_POWER in comm_params, then no data is sent from nRF51x22. This could have many reasons and I bailed out reviewing the app_uart_init() code as this is rather complicated. I know the serial adapter works with RTS/CTS in other applications (not using Segger debug port but one from FTDI). If others have had APP_UART_FLOW_CONTROL_LOW_POWER to work I would like to hear about it. The application is not using softdevice.
I wrote this note because the nRF51422-EK user manual, does not explain how to actually connect to the UART from the host, and a search in Keil documentation for "UART" or "Serial" gives an overwhelming number of hits. Surely one of them will be the right I just did not find it.
May I suggest that NS updates the nRF51422-EK user-manual with this vital piece of information or did I overlook something obvious?
