UART in nRF51822 Evaluation kit won't receive

[Allan]

I'm load the UART example (pca10001) to the Evaluation Kit, i can see using hyperterminal the messages send by the kit ( the Start message) but after that i wont be able to receive any input from the CPU, im using all the parameter given in the SDK webpage and cannot find the problem.

[Hung Bui]

@Allan: Could you upload the example you used ? It should be noted that when using UART with Evaluation Kit, you have to enable hardware flow control.

[Allan]

Thanks for the fast reply, here is the code, is one of the ones you provide for the evaluation kit, also if im not mistaken the flow control its enable, HWFC is set to true.

uart_example.rar

[Hung Bui]

Hi Allan,

I am sorry for the late response. I noticed that you might have selected nrf51822_xxaa_s110 in the Target drop down tab. When you select this option you would need to program softdevice at region 0 first because the application code will be flashed at address 0x14000 instead of 0x000000

I would suggest you to use nrf51822_xxaa target instead.

If the issue remains, could you run the device in debug mode and click stop to see the device stay at the loop to wait for NRF_UART0->EVENTS_RXDRDY != 1 ?

[Allan]

Thanks for the reply, i followed your suggestiong and used nrf51822_xxaa , and the problem persist, i cheked in degub mode and as you said, i stay in the loop waiting for RXDRDY, i also tried the loopback mode , connecting directly tx and rx and it would give me an error turning on the led. I also cheked that the connections SB9,SB10,SB11 and SB12 are not open.

[Hung Bui]

@Allan: I suspect that there would be an issue with the physical UART pins (RX, TX; RTS; CTS pins). Could you tried:

• Do loopback mode with HWFC = false.

• If Error LED still on, please try my attached example, in which I reconfigured the RX and TX pins to P0.00 and P0.01. If you connect them together (the 2 far right pins on P3), the Error LED should not lit up after reset.

uart_example - TestPins.zip