#include <rl_usb.h>

int usbh_hid_status (
  U8  ctrl,
  U8  dev_idx
);

The function usbh_hid_status retrieves the connection status of the HID device instance. The argument ctrl is the index of USB Host Controller. The argument dev_idx is the index of device instance.

The usbh_hid_status function is part of the RL-USB Host Class Driver software layer.

A boolean value indicating whether the HID device is connected and initialized.

usbh_hid_data_in, usbh_hid_data_in_callback, usbh_hid_data_out, usbh_hid_get_last_error, usbh_hid_kbd_getkey, usbh_hid_mouse_getdata, usbh_hid_parse_report_desc

#include <rl_usb.h>

int main (void)  {

  ..
  if (usbh_hid_status (0, 0))   // Check if HID keyboard 0 on controller 0 is connected
    break;
  ..
}