Application firmware hangs up in twi_wait() function

[Andreas]

Hello

I`m using the NORDIC nrf_drv_twi driver implementation from the PACK environment (version equivalent to SDK 8.1.0). Together with the S120 softdevice. If there is an active ble connection, somtimes the firmware hangs up in the twi_wait() function.

void twi_wait(void){
	do
	{
			__WFE();
	}while(m_xfer_done == false);}

Is there any known issue about priority problems or something like this, that could cause such a behaviour? The twi driver runs on APP_IRQ_PRIORITY_HIGH. If I set this priority to APP_IRQ_PRIORITY_LOW, the twi implementation completly wont work, if there is an active BLE connection. So I try to read out some data from the device via ble. This doesn`t even work, if the priority is set to LOW. If the priority is set to HIGH, it works, but sometimes the firmware hangs up in the twi_wait function. Any ideas?

Regards, BTprogrammer

[Kenneth]

Hi, I can't find any examples out of the box with both BLE and TWI at the moment. I think what would help here is if you have access to a logic analyzer so you can see what occurs on the serial interface. Also it might help to debug the events in twi_handler() for NRF_DRV_TWI_RX_DONE, NRF_DRV_TWI_TX_DONE, and NRF_DRV_TWI_ERROR. You should ensure that application interrupt priorities is set according to the softdevice specification document.

FYI: We are no longer maintaining pack, so you should download the latest nRF5 SDK in zip format.

[Andreas]

Hello Kenneth, interesting, I can confirm, that I do not get the error if I slow down the function which causes very much I2C transfers per second in background. My EEPROM_write() function where I get the error looks like this:

res = nrf_drv_twi_tx(&m_twi_eeprom, EEPROM_HW_ADDR, m_address, 2, true);
if(res==NRF_SUCCESS){
...
}
else
{
dbg_printf("Error transmitting I2C read address %d!\r", res);
return NRF_DRV_TWI_ERROR;
}

and the output I get on the terminal looks like this: Error transmitting I2C read address 1! So for me it is clear that I get the error value 1 from nrf_drv_twi_tx()