Solved
The maxium length of buffer for USB HID SetReport
Hi,
I would like to know why when I sent the 202 bytes from pc to dev-board via USB HID, the buffer size would only get 32 byte each time, (byte[0]-byte[31])*several times until finished print out all 202 bytes?
Couldn't it recieved whole 202 bytes then print out continuously from byte[0] to byte[201]?
ux_device_keyboard.c
/**
* @brief USBD_HID_Keyboard_SetReport
* This function is invoked when the host sends a HID SET_REPORT
* to the application over Endpoint 0.
* @PAram hid_instance: Pointer to the hid class instance.
* @PAram hid_event: Pointer to structure of the hid event.
* @retval status
*/
UINT USBD_HID_Keyboard_SetReport(UX_SLAVE_CLASS_HID *hid_instance,
UX_SLAVE_CLASS_HID_EVENT *hid_event)
{
UINT status = UX_SUCCESS;
/* USER CODE BEGIN USBD_HID_Keyboard_SetReport */
UX_PARAMETER_NOT_USED(hid_instance);
UX_PARAMETER_NOT_USED(hid_event);
//Receive Output report from PC
if (hid_event == UX_NULL || hid_event->ux_device_class_hid_event_length < 2)
return UX_ERROR;
uint8_t report_id = hid_event->ux_device_class_hid_event_buffer[0];
uint8_t *data = &hid_event->ux_device_class_hid_event_buffer[1];
UINT data_len = hid_event->ux_device_class_hid_event_length - 1;
if (report_id == 0x02 && data_len <= MAX_HID_OUTPUT_REPORT_SIZE)
{
// Copy the data to global buffer for later processing
memcpy(g_output_report_buffer, data, data_len);
g_output_report_length = data_len;
g_output_report_ready = 1;
}
/* USER CODE END USBD_HID_Keyboard_SetReport */
return status;
}
And the desriptor alos has been changed like below:
__ALIGN_BEGIN uint8_t USBD_HID_KEYBOARD_ReportDesc[]
__ALIGN_END =
{
/* USER CODE BEGIN USBD_HID_KEYBOARD_ReportDesc */
//Wedy Change for customized report
0x06, 0x00, 0xFF, /* USAGE PAGE (HID Device)*/\
0x09, 0xFF, /* USAGE (ASIC USAGE) */\
0xa1, 0x01, /* COLLECTION (Application) */\
0x15, 0x00, /* LOGICAL_MINIMUM (0) */\
0x25, 0xff, /* LOGICAL_MAXIMUM (255) */\
0x75, 0x08, /* REPORT_SIZE (8) */\
0x85, 0x01, /* REPORT_ID (1). This defines input to the host side */\
0x95, 0x10, /* REPORT_COUNT (16) */\
0x09, 0x01, /* USAGE (ASIC USAGE) */\
0x75, 0x08, /* REPORT_SIZE (8)*/\
0x81, 0x02, /* INPUT (Data,Var,Abs) (note: output from host) */\
0x85, 0x02, /* REPORT_ID (2). This defines output from the host side */\
0x95, 0xC9, /* REPORT_COUNT (201) */\
0x09, 0x01, /* USAGE (ASIC USAGE) */\
0x75, 0x08, /* REPORT_SIZE (8)*/\
0x91, 0x02, /* OUTPUT (Data,Var,Abs) (note: input to host) */\
/* USER CODE END USBD_HID_KEYBOARD_ReportDesc */
0xc0 /* End Collection */
};