Problems with changing the uart pins for the s120 ble_app_uart

[Eirik Nobuki Kosaka]

ble_app_uart_c2.rar

I want to connect two PCA10001's together, one with the ble_app_uart for s120 using sdk 8, and one with the experimental_ble_app_uart for s110 using sdk 7.2. I want these two to be connected to other devices over BLE.

I was told that i cannot use the original UART pins for this because these are directly connected to the J-segger, so i am trying to change the RX and TX pins to some of the other GPIO-pins (don't need flow control so i don't care too much for the RTS or CTS).

The idea is that i want to just receive data over BLE, and then send it to the next device over UART, which retransmits the data to a new device over BLE. I am able to switch pins and get the s110 part to work as wanted, but i cannot seem to change the s120 pins without meeting the problem which makes all LEDs turn on, i believe similar to this:

devzone.nordicsemi.com/.../

I was thinking of just changing the UART-part of the s120 to simple_uart, same as the s110 uses, or if there is a way for me to fix the problem so i can use the same UART as the s120 allready uses, but just change pins?

This is my first time using the nRF's or really programming a microcontroller at all so if there is anything to comment in general feel free to do so. Any help would be greatly appriciated

[Eirik Nobuki Kosaka]

Found out that i had to use a pull up resistor when changing the RX-pin to fix my problem, did not know that was the case.

[Hung Bui]

@Eirik: I just tested here, if you don't connect the pins to the peer device and just touch it with your hand, you will receive an ERROR event on UART, see UART0_IRQHandler(). The error code telling it's FRAMING error and BREAK error.

After that the IRQ handle will propagate the error back to uart_event_handle() in main with APP_UART_COMMUNICATION_ERROR and end up in the assert handler app_error_handler() where it will stuck at while(1) loop.

So I think it's pretty much normal when we add some noise to the UART line and then it end up with that error (not a system reset) .

This doesn't explain why you need the pull up though.