USB Mouse using PIC18F4550 microcontroller

PIC18F4550 microcontroller has USB module which can work as a HID (Human Interface Device). The USB HID device doesn't need any additional driver because it's already installed in most of modern operating systems.
Using PIC18F4550 as a HID device we can easily transfer data between PC and the microcontroller as shown at the following URL:
PIC18F4550 USB HID Example using CCS PIC C
This topic shows how to build a simple USB HID mouse using PIC18F4550 microcontroller (PIC18F2550 can also be used).
Required Components:

• PIC18F4550 Microcontroller ( or PIC18F2550) 
• 8MHz Crystal Oscillator
• 2 x 22pF capacitors
• 470nF Capacitor
• 6 Push-Buttons
• USB Connector
• +5V Power Supply (USB VCC can be used)
• Protoboard
• Jumper Wires

Project circuit schematic is shown below:

USB Mouse using PIC18F4550 CCS C code:
The CCS PIC C compiler has USB Mouse driver which allows us to build a USB mouse more easily. The following line is used to add this driver to this project:
#include <usb_desc_mouse.h>
In this project there is no need to receive data from the HID device, we have only to send data to this device using the following line:
usb_put_packet(1, out_data, 4, USB_DTS_TOGGLE);
Where out_data is an array of 4 elements (4 bytes):
Byte 1 corresponds to button status. The left button of the mouse is represented by 0x01 and the right button is represented by 0x03.
Byte 2 and byte 3 correspond to X axis and Y axis directions.
Byte 4 for the mouse wheel which is not used in this project.
The X axis and Y axis bytes are signed int8 which can vary from -127 to 127. The ( - ) sign indicates direction ( for X axis left/right and for Y axis up/down) and the number means number of steps at a time.
The complete C code is as the one below:

// PIC18F4550 USB Mouse CCS C code
// http://ccspicc.blogspot.com/
// electronnote@gmail.com
// Use at your own risk

#include <18F4550.h>
#fuses  HSPLL PLL2 CPUDIV1 USBDIV VREGEN NOMCLR
#use delay(clock = 48000000)
#include <usb_desc_mouse.h>
#include<pic18_usb.h>
#include<usb.c>
#use fast_io(B)

char out_data[4];
void main(){
  setup_adc_ports(NO_ANALOGS);                          // Configure all AN pins as digital
  output_b(0);                                          // PORTB initial state
  set_tris_b(0x3F);                                     // Configure RB0 to RB5 as inputs
  port_b_pullups(TRUE);                                 // Enable PORTB pull-ups
  usb_init_cs();                                        // Initialize USB hardware
  delay_ms(1000);
  while(TRUE){
    usb_task();
    if(usb_enumerated()){                               // If the device has been enumerated by the PC
      while(!input(PIN_B0)){
        out_data[0] = 0;
        out_data[1] = 1;
        out_data[2] = 0;
        out_data[3] = 0;
        usb_put_packet(1,out_data,4,USB_DTS_TOGGLE);
      }
      while(!input(PIN_B1)){
        out_data[0] = 0;
        out_data[1] = -1;
        out_data[2] = 0;
        out_data[3] = 0;
        usb_put_packet(1,out_data,4,USB_DTS_TOGGLE);
      }
      while(!input(PIN_B2)){
        out_data[0] = 0;
        out_data[1] = 0;
        out_data[2] = 1;
        out_data[3] = 0;
        usb_put_packet(1,out_data,4,USB_DTS_TOGGLE);
      }
      while(!input(PIN_B3)){
        out_data[0] = 0;
        out_data[1] = 0;
        out_data[2] = -1;
        out_data[3] = 0;
        usb_put_packet(1, out_data, 4, USB_DTS_TOGGLE);
      }
      while(!input(PIN_B4)){
        out_data[0] = 1;
        out_data[1] = 0;
        out_data[2] = 0;
        out_data[3] = 0;
        usb_put_packet(1,out_data,4,USB_DTS_TOGGLE);
      }
      while(!input(PIN_B5)){
        while(!input(PIN_B5));
        out_data[0] = 3;
        out_data[1] = 0;
        out_data[2] = 0;
        out_data[3] = 0;
        usb_put_packet(1,out_data,4,USB_DTS_TOGGLE);
      }
        out_data[0] = 0;
        out_data[1] = 0;
        out_data[2] = 0;
        out_data[3] = 0;
        usb_put_packet(1,out_data,4,USB_DTS_TOGGLE);
    }
  }
}

USB Mouse using PIC18F4550 video:
This video shows a simple hardware circuit connected to PC where the screen is divided into two parts, the left part is a recorded video of the PC screen and the right side shows the hardware circuit.