Hello,
I found an example on the internet of a project but I don't understand the usefulness of using a Timer 7. Could you tell me why ? Thanks in advance.
__IO uint32_t usTick;
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
/* Prevent unused argument(s) compilation warning */
if(htim==&htim7){
usTick++;
}
/* NOTE : This function Should not be modified, when the callback is needed,
the __HAL_TIM_PeriodElapsedCallback could be implemented in the user file
*/
}
void delay_us(__IO uint32_t Delay){
uint32_t t=usTick;
uint32_t wait = Delay;
while( usTick - t < wait);
}
int main(void)
{
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* Configure the system clock */
SystemClock_Config();
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_TIM7_Init();
/*if (HAL_TIM_Base_Start(&htim7) != HAL_OK) {
_Error_Handler(__FILE__, __LINE__);
}*/
if (HAL_TIM_Base_Start_IT(&htim7) != HAL_OK) {
_Error_Handler(__FILE__, __LINE__);
}
MX_I2C1_Init();
MX_I2S2_Init();
HAL_Delay(100);
audio.init();
bool ptt=HAL_GPIO_ReadPin(GPIOE,PTT_SWITCH);
bool pttstate=ptt;
uint16_t index = 0;
uint16_t buf = 0;
audio.set_volume(0);
/* Infinite loop */
while (1)// read power switch
{
ptt=HAL_GPIO_ReadPin(GPIO_PINS,PTT_SWITCH);
if(ptt!=pttstate){
if(ptt==0){
audio.start_receive();
for(buf=0;buf<32;buf++){
for(index=0;index < AUDIO_BUF_SIZE;index++){
HAL_I2SEx_TransmitReceive(&hi2s2, &i2s_zero,&i2s_buf[buf][index], 1,0xFF);
}
}
audio.start_play();
for(buf=0;buf<32;buf++){
for(index=0;index < AUDIO_BUF_SIZE;index++){
HAL_I2SEx_TransmitReceive(&hi2s2, &i2s_buf[buf][index],&i2s_zero, 1,0xFF);
}
}
}
pttstate=ptt;
}
}
}
