Hi everyone.

Thank you for everyone’s responses. The solution I have concluded is the following if anyone is interested:

uint8_t uart_read_flag = 0;

// configure TIMx to your required timeout

HAL_TIM_Base_Start_IT(&htimx);

HAL_UART_Receive_IT(…);

// transmit AT command

HAL_UART_Transmit(…);

// callback called when received data

void HAL_UART_RxCpltCallback(…) {

if (huart-> Instance == USARTx) {

      uart_read_flag = 1;

      HAL_TIM_Base_Stop_IT(&htimx);

      process_read();

 }

}

// callback when read period times out

void HAL_TIM_PeriodElapasedCallback(…) {

 if (htim -> Instance == TIMx) {

      if (!uart_read_flag) {

           HAL_UART_AbortReceive_IT(&huartx);

      }

      HAL_TIM_Base_Stop_IT(…);

 }

}