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Keyboard & Mouse

HID Keyboard and Mouse

In this example, we will be utilizing the USBHIDBootKbdAndMouse example from the USB_Host_Shield_2.0 Arduino library. This example can be found in the File dropdown menu (i.e. (1) File > Examples > USB Host Shield Library 2.0 > HID > USBHIDBootKbdAndMouse). Once the example has been opened, users should see the USBHIDBootKbdAndMouse.ino example sketch.

  1. Select the USBHIDBootKbdAndMouse example sketch from the File drop-down menu.
USBHIDBootKbdAndMouse.ino 
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#include <hidboot.h>
#include <usbhub.h>

// Satisfy IDE, which only needs to see the include statment in the ino.
#ifdef dobogusinclude
#include <spi4teensy3.h>
#endif
#include <SPI.h>

class MouseRptParser : public MouseReportParser
{
  protected:
    void OnMouseMove(MOUSEINFO *mi);
    void OnLeftButtonUp(MOUSEINFO *mi);
    void OnLeftButtonDown(MOUSEINFO *mi);
    void OnRightButtonUp(MOUSEINFO *mi);
    void OnRightButtonDown(MOUSEINFO *mi);
    void OnMiddleButtonUp(MOUSEINFO *mi);
    void OnMiddleButtonDown(MOUSEINFO *mi);
};
void MouseRptParser::OnMouseMove(MOUSEINFO *mi)
{
  Serial.print("dx=");
  Serial.print(mi->dX, DEC);
  Serial.print(" dy=");
  Serial.println(mi->dY, DEC);
};
void MouseRptParser::OnLeftButtonUp (MOUSEINFO *mi)
{
  Serial.println("L Butt Up");
};
void MouseRptParser::OnLeftButtonDown   (MOUSEINFO *mi)
{
  Serial.println("L Butt Dn");
};
void MouseRptParser::OnRightButtonUp    (MOUSEINFO *mi)
{
  Serial.println("R Butt Up");
};
void MouseRptParser::OnRightButtonDown  (MOUSEINFO *mi)
{
  Serial.println("R Butt Dn");
};
void MouseRptParser::OnMiddleButtonUp   (MOUSEINFO *mi)
{
  Serial.println("M Butt Up");
};
void MouseRptParser::OnMiddleButtonDown (MOUSEINFO *mi)
{
  Serial.println("M Butt Dn");
};

class KbdRptParser : public KeyboardReportParser
{
    void PrintKey(uint8_t mod, uint8_t key);

  protected:
    void OnControlKeysChanged(uint8_t before, uint8_t after);
    void OnKeyDown  (uint8_t mod, uint8_t key);
    void OnKeyUp    (uint8_t mod, uint8_t key);
    void OnKeyPressed(uint8_t key);
};

void KbdRptParser::PrintKey(uint8_t m, uint8_t key)
{
  MODIFIERKEYS mod;
  *((uint8_t*)&mod) = m;
  Serial.print((mod.bmLeftCtrl   == 1) ? "C" : " ");
  Serial.print((mod.bmLeftShift  == 1) ? "S" : " ");
  Serial.print((mod.bmLeftAlt    == 1) ? "A" : " ");
  Serial.print((mod.bmLeftGUI    == 1) ? "G" : " ");

  Serial.print(" >");
  PrintHex<uint8_t>(key, 0x80);
  Serial.print("< ");

  Serial.print((mod.bmRightCtrl   == 1) ? "C" : " ");
  Serial.print((mod.bmRightShift  == 1) ? "S" : " ");
  Serial.print((mod.bmRightAlt    == 1) ? "A" : " ");
  Serial.println((mod.bmRightGUI    == 1) ? "G" : " ");
};

void KbdRptParser::OnKeyDown(uint8_t mod, uint8_t key)
{
  Serial.print("DN ");
  PrintKey(mod, key);
  uint8_t c = OemToAscii(mod, key);

  if (c)
    OnKeyPressed(c);
}

void KbdRptParser::OnControlKeysChanged(uint8_t before, uint8_t after) {

  MODIFIERKEYS beforeMod;
  *((uint8_t*)&beforeMod) = before;

  MODIFIERKEYS afterMod;
  *((uint8_t*)&afterMod) = after;

  if (beforeMod.bmLeftCtrl != afterMod.bmLeftCtrl) {
    Serial.println("LeftCtrl changed");
  }
  if (beforeMod.bmLeftShift != afterMod.bmLeftShift) {
    Serial.println("LeftShift changed");
  }
  if (beforeMod.bmLeftAlt != afterMod.bmLeftAlt) {
    Serial.println("LeftAlt changed");
  }
  if (beforeMod.bmLeftGUI != afterMod.bmLeftGUI) {
    Serial.println("LeftGUI changed");
  }

  if (beforeMod.bmRightCtrl != afterMod.bmRightCtrl) {
    Serial.println("RightCtrl changed");
  }
  if (beforeMod.bmRightShift != afterMod.bmRightShift) {
    Serial.println("RightShift changed");
  }
  if (beforeMod.bmRightAlt != afterMod.bmRightAlt) {
    Serial.println("RightAlt changed");
  }
  if (beforeMod.bmRightGUI != afterMod.bmRightGUI) {
    Serial.println("RightGUI changed");
  }

}

void KbdRptParser::OnKeyUp(uint8_t mod, uint8_t key)
{
  Serial.print("UP ");
  PrintKey(mod, key);
}

void KbdRptParser::OnKeyPressed(uint8_t key)
{
  Serial.print("ASCII: ");
  Serial.println((char)key);
};

USB     Usb;
USBHub     Hub(&Usb);

HIDBoot < USB_HID_PROTOCOL_KEYBOARD | USB_HID_PROTOCOL_MOUSE > HidComposite(&Usb);
HIDBoot<USB_HID_PROTOCOL_KEYBOARD>    HidKeyboard(&Usb);
HIDBoot<USB_HID_PROTOCOL_MOUSE>    HidMouse(&Usb);

KbdRptParser KbdPrs;
MouseRptParser MousePrs;

void setup()
{
  Serial.begin( 115200 );
#if !defined(__MIPSEL__)
  while (!Serial); // Wait for serial port to connect - used on Leonardo, Teensy and other boards with built-in USB CDC serial connection
#endif
  Serial.println("Start");

  if (Usb.Init() == -1)
    Serial.println("OSC did not start.");

  delay( 200 );

  HidComposite.SetReportParser(0, &KbdPrs);
  HidComposite.SetReportParser(1, &MousePrs);
  HidKeyboard.SetReportParser(0, &KbdPrs);
  HidMouse.SetReportParser(0, &MousePrs);
}

void loop()
{
  Usb.Task();
}

Users will need to connect an HID device (keyboard and/or mouse) to the USB-C host shield with a USB cable, before running the example. After the example begins, users should see an output in the Serial Monitor with print out based on the user's interaction with their HID device.