NRF51 Uart Overrun

[Epimeth]

Hi,

I use a GPS Modul to send data via uart to the NRF 51 and then I send the string via SPI and fatfs to the SD CArd.

I see the LED4 blinking and during the debugging I can see the Uart has an overrun event. The Uart has no flow control and a baud rate from 9600.

The overrun is calling during the fatfs. So I expect losing data by writing to the SD CArd, but all data is written without any failure.

I use  normal libary, no softdevice and calling the fatfs from the main loop,

What means the LED 4, if it blinking and why i have an uart overrun event but nothing happen with the data?

[Jørgen Holmefjord]

You should consider moving to nRF52 series. nRF52 series have EasyDMA on SPI and UART peripherals, allowing the peripherals to transmitt/receive data while CPU is busy handling other events/tasks.