Question
How to establish communication between 93LC66B and NUCLEO-G474RE ?
According to 93LC66 communication the 93LC66B variant is a rotated variant. How to establish communication between NUCLEO-G474RE and this EEPROM using SPI ? I've tried many approaches but none worked, always get 0 from EEPROM but it should be FF, I think. Is there need to add delays or change Nucleo clock ? I set prescaler to 256 but still no communication. I bring CS line hig when want to communicate with EEPROM and low when done but I always read 0.
Here's the code (while loop and SPI settings generated by STM32CubeIDE:
/* USER CODE BEGIN WHILE */
while (1)
{
high_byte = 0b00001100;
low_byte = 0;
printf("Instruction sent: %d\n", high_byte);
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_12, GPIO_PIN_SET);
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_14, GPIO_PIN_SET);
HAL_SPI_Transmit(&hspi2, (uint8_t*)&high_byte, 1, HAL_MAX_DELAY);
HAL_SPI_Transmit(&hspi2, (uint8_t*)&low_byte, 1, HAL_MAX_DELAY);
uint8_t received_byte = 1;
//if (HAL_SPI_DeInit(&hspi2) != HAL_OK)
//{
// printf("SPI CLKPOL change failed\n");
// }
//hspi2.Init.CLKPolarity = SPI_POLARITY_HIGH;
//if(HAL_SPI_Init(&hspi2) != HAL_OK)
// {
// printf("Failed to change CLKPOL\n");
//}
//HAL_Delay(16);
switch(HAL_SPI_Receive(&hspi2, &received_byte, 1, HAL_MAX_DELAY))
{
case HAL_OK:
printf("SPI HAL OK\n");
break;
case HAL_ERROR:
printf("SPI HAL ERROR\n");
break;
case HAL_TIMEOUT:
printf("SPI HAL TIMEOUT\n");
break;
}
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_12, GPIO_PIN_RESET);
printf("Received data: 0x%x\n", received_byte);
//if (HAL_SPI_DeInit(&hspi2) != HAL_OK)
//{
// printf("SPI CLKPOL change failed\n");
//}
//hspi2.Init.CLKPolarity = SPI_POLARITY_LOW;
//if(HAL_SPI_Init(&hspi2) != HAL_OK)
//{
// printf("Failed to change CLKPOL\n");
//}
HAL_Delay(500);
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
/* USER CODE END SPI2_Init 1 */
/* SPI2 parameter configuration*/
hspi2.Instance = SPI2;
hspi2.Init.Mode = SPI_MODE_MASTER;
hspi2.Init.Direction = SPI_DIRECTION_2LINES;
hspi2.Init.DataSize = SPI_DATASIZE_8BIT;
hspi2.Init.CLKPolarity = SPI_POLARITY_LOW;
hspi2.Init.CLKPhase = SPI_PHASE_1EDGE;
hspi2.Init.NSS = SPI_NSS_SOFT;
hspi2.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_128;
hspi2.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspi2.Init.TIMode = SPI_TIMODE_DISABLE;
hspi2.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
hspi2.Init.CRCPolynomial = 7;
hspi2.Init.CRCLength = SPI_CRC_LENGTH_DATASIZE;
hspi2.Init.NSSPMode = SPI_NSS_PULSE_DISABLE;
if (HAL_SPI_Init(&hspi2) != HAL_OK)
{
Error_Handler();
}