if (ir_in == 0)              // we wait for 562us mark signal
                     IR_Timer_Count ++;        // increment timer counter

 if (ir_in == 1)

if ((IR_Timer_Count > 3) && (IR_Timer_Count < 7))// 300us  and 700us

 IR_State = 4;

IR_Timer_Count = 0;

if (IR_Received_Flag == 0xFF)
                                                {
                                                 IR_Received_Flag = 1;
                                                 IR_State = 0;       // we have received 4 bytes successfully!
                                                }

else{
                                         IR_State = 0;          // reset IR state because we did not got required 9ms mark
                                         IR_Timer_Count = 0;    // reset timer counter
                                         }

if (ir_in == 1)              // we wait for space signal
                     IR_Timer_Count ++;        // increment timer counter

for(bytenum = 0; bytenum < 4; bytenum++)        // 4 bytes to send
           {
             for(bitnum = 0; bitnum < 8; bitnum++)    // 8 bits LSB first
                  {
                   PWM1_Start();                           // mark
                   led=1;
                   Delay_us(560);                          // 560uS mark for '0' or '1'
                   PWM1_Stop();                            // space
                   led=0;
                   if(ir_byte[bytenum] & (1 << bitnum))     // test bit <bitnum>
                       {
                         Delay_us(1680);                     // 1.68mS space for a '1'
                       }
                  else{
                       Delay_us(560);                      // 560uS space for a '0'
                     }
                  }
           }

if (ir_in == 0)   if ((IR_Timer_Count > 3) && (IR_Timer_Count < 19))// between 300us  and 1900us

else
                      {
                        IR_State = 0;          // reset IR state because we did not got required signal
                        IR_Timer_Count = 0;    // reset timer counter
                      }
                  break;

IR_Received_byte[IR_Byte_Count] = (IR_Received_byte[IR_Byte_Count] >> 1);
                                             IR_Bit_Count ++;       // increment bit counter
                                             if (IR_Timer_Count > 8) IR_Received_byte[IR_Byte_Count] += 0x80;   // we have received "1"

                                             if (IR_Bit_Count == 8)
                                                     {
                                                      IR_Bit_Count = 0;   // reset bit count
                                                      IR_Byte_Count ++;   // increment byte count
                                                     }
                                            if (IR_Byte_Count == 4)  IR_Received_Flag = 0xFF;

                                            IR_State = 3;          // go to next state (wait for 562us mark)
                                            IR_Timer_Count = 0;    // reset timer counter

IR_Received_byte[IR_Byte_Count] = (IR_Received_byte[IR_Byte_Count] >> 1);

IR_Bit_Count ++;

if (IR_Timer_Count > 8) IR_Received_byte[IR_Byte_Count] += 0x80;   // we have received "1"

if (IR_Bit_Count == 8)
                                                     {
                                                      IR_Bit_Count = 0;   // reset bit count
                                                      IR_Byte_Count ++;   // increment byte count
                                                     }