[STM32F439] Could not receive USB CDC Interrupt IN transfer data

[KTuz.1]

As title

I generate USB CDC with STM32CubeMX,

and try to send data by using interrupt transfer end point 0x81

I try to usb Bushound to receive data, but it could not revive any data from CDC interrupt IN.

Is there any things that i should be modify?

Experiment In main while send 1 byte,

(1) OK

(2) FAIL

1 [Bulk]

USBD_LL_Transmit(&hUsbDeviceFS,CDC_IN_EP ,&data, 1)

2 [Interrupt]

USBD_LL_Transmit(&hUsbDeviceFS,CDC_CMD_EP,&data, 1)

[Pavel A.]

You cannot transmit anything thru any endpoint until the host gives you IN token.

Do you get IN requests from host?

-- pa

[KTuz.1]

Hi Pavel

I am new with USB, where could i know MCU receive IN request?

Thank you