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I have supplied a pre-compiled HEX file, so you don’t have to worry about installing additional assemblers or having to compile things yourself. You will however need to get the program onto the chip. If you don’t know how to program One of the simplest and cheapest ways of doing this is by building a PIC, I would suggest you do some research on the JDM type programmer, an even smaller . This is a tiny PCB that allows you to program which plugs into the chip through an RS232 port / Comm Port of a PC, in which you place the PIC and then program it using freeware such as PikLab if you’re a Linux user or ICProg if windows is your preferred PC OS. A quick warning: I'm told that the JDM doesn't work on Laptop ComComm-ports because they don't supply the required 12V, so keep this in mind if you build one. The total price to build a JDM programmer should be under 2€.You'll find plenty of information about the JDM programmer and the programs mentioned above, by doing a quick search of the web, but to make things a little easier, I've included the circuit diagram of one popular design. This isn't my design, you'll find it all over the internet, but it's a good and extremely cheap way of getting your PIC programmed. I have also included a PCB layout for this in the resources section below. The layout also includes a 5 pin header connection which allows you to access the 5 pins required to program almost any PIC, so with a simple adapter, this circuit could be used to program a huge range of PICs and not just the 16F84. For future projects perhaps?  [[Image:JDM_Prog.PNG|600px|centre]]  D1 is a 5.1V Zener Diode, the transistor is a BC547 and the Capacitor is a 100µf electrolytic capacitor (polarity is important with these). The two resistors are standard 1/4W resistors. A standard IC socket should be OK. Note also that there is a bridge wire beside the capacitor on the Sub-D connector side. The programmer takes it's power from the RS232 port and needs no external supply. When programming the 16F84 using ICProg or PikLab, the Oscillator and Fuse settings need to be correct. The correct settings for this project are: Oscillator = XT, WDT = Unchecked (off), PWRT = Checked (On) and CP = Unchecked (Off). Make sure these are set properly before programming the PIC, otherwise your mouse adapter won't work. The finished programmer should look something like this:  [[Image:JDM_Pic.png|400px|centre]]