Hello, at the moment I have a problem with my oscilloscope and I have to fix it...
My code(sorry for code quality but at the moment is only a test), I followed the datasheet flowchart(image in attach).
Do you think that I make some mistakes?
The slave seems to send an ACK at the moment.
I have 2 questions:
1) Sometimes at the end of the transmission, the TC bit remain low but I notices that if I put some delay before the TC check it work(as if I had to wait a certain time first, but in the flowchat I don't see this)
2) It's correct that for the last byte TXIS remain low?
Thanks a lot!
Simeon
void i2c_enable()
{
RCC->IOPENR |= RCC_IOPENR_GPIOBEN_Msk;
RCC->APBENR1 |= RCC_APBSMENR1_I2C1SMEN_Msk;
GPIOB->MODER &= ~(GPIO_MODER_MODE8_Msk | GPIO_MODER_MODE9_Msk);
GPIOB->MODER |= (GPIO_MODER_MODE8_1 | GPIO_MODER_MODE9_1);
GPIOB->OSPEEDR |= (GPIO_OSPEEDR_OSPEED8_1 | GPIO_OSPEEDR_OSPEED9_1);
GPIOB->AFR[1] |= GPIO_AFRH_AFSEL8_1
| GPIO_AFRH_AFSEL8_2
| GPIO_AFRH_AFSEL9_1
| GPIO_AFRH_AFSEL9_2;
GPIOB->OTYPER |= (GPIO_OTYPER_OT8 | GPIO_OTYPER_OT9);
I2C1->CR1 &= ~(I2C_CR1_PE_Msk); //clean PE bit
//clock configuration
I2C1->TIMINGR |= 1 << I2C_TIMINGR_PRESC_Pos
| 2 << I2C_TIMINGR_SDADEL_Pos
| 3 << I2C_TIMINGR_SCLDEL_Pos
| 3 << I2C_TIMINGR_SCLH_Pos
| 9 << I2C_TIMINGR_SCLL_Pos;
I2C1->CR1 |= I2C_CR1_PE_Msk;
}
void i2cSendStartCondition()
{
while((I2C1->ISR & I2C_ISR_BUSY_Msk)) {
printf("BUS not free!!!\r\n"); // wait for free bus
}
I2C1->CR2 |= I2C_CR2_START_Msk; // SEND START CONDITION
while ((I2C1->CR2 & I2C_CR2_START_Msk)) {
//start = 0, wait for start sended on BUS
printf("Waiting\r\n");
if (I2C1->ISR & I2C_ISR_NACKF_Msk) {
printf("ERROR: NACK received\r\n");
return;
}
}
while (!(I2C1->ISR & I2C_ISR_TXIS_Msk)) {
printf("Wait for ack\r\n");
if (I2C1->ISR & I2C_ISR_NACKF_Msk) {
printf("ERROR: NACK received\r\n");
return;
}
}
}
void i2cMasterSendData2(uint8_t slaveAddr, uint8_t addr, uint8_t *data, uint8_t len)
{
i2cMasterInit(slaveAddr, false);
I2C1->TXDR = addr;
for (int i = 0; i < len; i++) {
while (!(I2C1->ISR & I2C_ISR_TXIS_Msk)) {
printf("Wait for TXIS\r\n");
if (I2C1->ISR & I2C_ISR_NACKF_Msk) {
printf("ERROR: NACK received\r\n");
return;
}
}
printf("send data");
I2C1->TXDR = data[i];
}
if ((I2C1->ISR & I2C_ISR_TC_Msk)) {
printf("TC setted: %u\r\n", I2C1->ISR);
//send stop condition
I2C1->CR2 |= I2C_CR2_STOP_Msk;
} else {
printf("ISR: %u, \r\n", I2C1->ISR);
printf("TC not setted\r\n");
}
}
