Hi.
We are using nRF52833 (on BL653 module) where UART0 and UART1 are used for communication purposes (one with STM MUC and the other with quectel modem). Current solution uses SDK 17.0.2, softdevice and freeRTOS, where async libuarte support is used for uart communication. The main problem is that, from time to time (every couple of minutes), we get a HardFault. But only when both are active. If we disable on of them, the code looks to work as expected.
Currently, the UARTs are defined as (using app_timer):
NRF_LIBUARTE_ASYNC_DEFINE(libuarte, 1, 4, NRF_LIBUARTE_PERIPHERAL_NOT_USED, NRF_LIBUARTE_PERIPHERAL_NOT_USED, 1024, 3);
NRF_LIBUARTE_ASYNC_DEFINE(quectel_libuarte, 0, 3, NRF_LIBUARTE_PERIPHERAL_NOT_USED, NRF_LIBUARTE_PERIPHERAL_NOT_USED, 1024, 3);