I use a STM32F429ZI-DISCO board that was programmed using STM32CubeMX's Code generation for a USB-CDC-Host on high speed. To generate some input data I use a Teensy3.6 as an arduino Board set up as a serial communication device. The data sent by the Teensy can be read correctly with a PC and a serial terminal (e.g. HTerm).
However, I am not able to read the same Data with the STM-DISCO. I used the default installment from STM32CubeMX having tweaked the LineCoding to my specific serial port inside the init-function as shown below.
...
void MX_USB_HOST_Init(void)
{
/* USER CODE BEGIN USB_HOST_Init_PreTreatment */
// TODO Create LineCodingType for MM30
CDC_LineCodingTypeDef my_Port_pref;
/* USER CODE END USB_HOST_Init_PreTreatment */
/* Init host Library, add supported class and start the library. */
USBH_Init(&hUsbHostHS, USBH_UserProcess, HOST_HS);
USBH_RegisterClass(&hUsbHostHS, USBH_CDC_CLASS);
my_Port_pref.b.dwDTERate = 9600;
my_Port_pref.b.bCharFormat = 0x00; // 0 - 1 SB | 1 - 1,5 SB | 2 - 2 SB
my_Port_pref.b.bParityType = 0x00;
my_Port_pref.b.bDataBits = 0x08;
USBH_CDC_SetLineCoding(&hUsbHostHS, &my_Port_pref);
USBH_Start(&hUsbHostHS);
/* USER CODE BEGIN USB_HOST_Init_PostTreatment */
/* USER CODE END USB_HOST_Init_PostTreatment */
}
...After that, i used the USB_BulkRecieveData() function inside of the USBH_UserProcess to read some data as soon as a USB device is connected.
static void USBH_UserProcess (USBH_HandleTypeDef *phost, uint8_t id)
{
/* USER CODE BEGIN CALL_BACK_1 */
uint16_t my_buffer_len = 512;
uint8_t my_usb_buffer[my_buffer_len];
switch(id)
{
case HOST_USER_SELECT_CONFIGURATION:
break;
case HOST_USER_DISCONNECTION:
Appli_state = APPLICATION_DISCONNECT;
HAL_GPIO_WritePin(LED_GREEN_GPIO_Port, LED_GREEN_Pin, FALSE);
HAL_GPIO_WritePin(LED_RED_GPIO_Port, LED_RED_Pin, FALSE);
break;
case HOST_USER_CLASS_ACTIVE:
Appli_state = APPLICATION_READY;
HAL_GPIO_WritePin(LED_GREEN_GPIO_Port, LED_GREEN_Pin, TRUE);
break;
case HOST_USER_CONNECTION:
Appli_state = APPLICATION_START;
HAL_GPIO_WritePin(LED_RED_GPIO_Port, LED_RED_Pin, TRUE);
USBH_BulkReceiveData(phost, my_usb_buffer, my_buffer_len, 0);
break;
default:
break;
}
/* USER CODE END CALL_BACK_1 */
}The data in the buffer after executing the receive-function does not look like the data that has been read by the PC. The first 200Bytes look random. Afterwards it reads a lot of zeros (00)h. Therefore I suspect that there is an fault in the initiation or the setup of the usb-serial host.
Do I need to use a different recieve function or do I need to set up the serial parameters at another position?
I tried using the USB-Host manual without success and the most tutorials go by using the DISCO board as a device and not as a master.
