SMBus blocked and how to recover it

[LsnLeeJW]

Hi ST tesam,

When I use the HAL of STM32C031, I have some trouble about SMBus.

Q1:When I use the SMBus of STM32C031 series. If I do not got the feedback from the slave, sometimes the SDA will pull down(similar to the yellow line show as below) and system was blocked. How can I do to end this communication and recover SMBus.

 HAL_SMBUS_Master_Transmit_IT( &hsmbus1, BATTERY_ADD, &ucCalTemp[ 1 ], 1, 
 SMBUS_FIRST_FRAME );
 while (hsmbus1.State == HAL_SMBUS_STATE_MASTER_BUSY_TX)
 {
 uOverT--;
 if(uOverT == 0)
 {
 //HERE I want to recover the SMBus 
 }
 return HAL_ERROR;
 }
 }

 

Q2: If I got a NACK signal , How can I do to send a ‘STOP’ signal. Is there any function I can use if I do not re-initial the pin to GPIO_OUT mode. And how can I do to detect the NACK. (could I use the function HAL_SMBUS_EV_IRQHandler to detect it.)

 

Thanks for your help.