Question
I2C driver always busy after first use
I'm using the HAL_I2C_Master_Transmit_DMA driver on an STM32L412. I am transmitting 8 bytes of data to an external 4 channel I2C DAC - I have only one device on the bus. The first use of the driver works fine as confirmed by using an oscilloscope on i2c bus, the DAC updates and there is a stop condition. From then on the driver always returns a busy status - specifically at the point where the driver uses HAL_DMA_Start_IT .
Ive read other people mention the same (or very similar) problems when using the I2C HAL drivers, is there a fix for this?
setup for i2c
static void MX_I2C2_Init(void)
{
hi2c2.Instance = I2C2;
hi2c2.Init.Timing = 0x00610611;
hi2c2.Init.OwnAddress1 = 192;
hi2c2.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
hi2c2.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
hi2c2.Init.OwnAddress2 = 0;
hi2c2.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
hi2c2.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
hi2c2.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
if (HAL_I2C_Init(&hi2c2) != HAL_OK)
{
Error_Handler();
}
/** Configure Analogue filter
*/
if (HAL_I2CEx_ConfigAnalogFilter(&hi2c2, I2C_ANALOGFILTER_ENABLE) != HAL_OK)
{
Error_Handler();
}
/** Configure Digital filter
*/
if (HAL_I2CEx_ConfigDigitalFilter(&hi2c2, 0) != HAL_OK)
{
Error_Handler();
}
}setup for DMA
static void MX_DMA_Init(void)
{
/* DMA controller clock enable */
__HAL_RCC_DMA1_CLK_ENABLE();
/* DMA interrupt init */
/* DMA1_Channel4_IRQn interrupt configuration */
HAL_NVIC_SetPriority(DMA1_Channel4_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(DMA1_Channel4_IRQn);
}