I would like to send data from the Nucleo Board F401RE or F411RE to the PC via the USB interface. The data should be transmitted via a virtual COM port (CDC protocol) with Full Speed (FS). Unfortunately this does not work! For testing I use also a Nucleo-L476RG Board. With the Nucleo-L476RG board the data transfer works but when I try to implement it on the Nucleo-F401RE or -F411RE Board I cannot connect to the COM port. The port is added in Windows but it cannot be opened. What do I have to change to make it work on the Nucleo-F4X1RE Boards? It must run on the F4 chip because the program should run on a developer board where the STM32F401CEU6 (or a STM32F411CEU6) chip is mounted.
The PC runs with Windows 10.
The used tool chain is:
CubeMX 5.5.0 and SW4STM32 Version Neon.3 Release 4.6.3.
USB is connected as follows:
GND connected to Nucleo
VCC (+5V) not connected
D+ connected to PA12
D- connected to PA11
The following is set in CubeMX:
Connectivity:
- USB_OTG_FS / Device_Only
- "Activate_SOF" and "Activate_VBUS" are inactive.
- Middleware: USB_Device / Communication Device Class (Virtual Port Com)
In the main.c programme the following additions have been made:
1)
/* USER CODE BEGIN 2 */
HAL_Delay(1000);
uint8_t buffer[] = "Hello, world!\r\n";
2)
/* USER CODE BEGIN WHILE */
while (1)
{
CDC_Transmit_FS(buffer, sizeof(buffer));
HAL_Delay(1000);
HAL_GPIO_TogglePin(LD2_GPIO_Port,LD2_Pin);
