Wireless Presentation Mouse

I have been assigned a project (software part) - wireless presentation mouse.
It consists of
1. Transmitter.
2. Receiver.
Major Parts:
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Transmitter
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(Infrared Emitter(TSAL6200 ), Encoder Microcontroller(PIC 16F627), Laser Pointer, Battery)
Receiver
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(Infrared receiver(TSOP4836 ), Decoder Microcontroller(PIC 16C745), USB connector)


1. How to get started writing the firmware for encoding the signals and transmit thru' the IR emitter?.
Please give some suggestions on this or give me the related link to start with?.

2. Are there sample firmware code available for encoding the signals and transmit through the IR emitter ?.
Please give me the related link.