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copied!<p>You're going to have to setup a bunch of different bit masks to get the actual opcode from the 16-bit word in combination with a finite state machine in order to interpret those opcodes since it appears that there are some complications in how the opcodes are encoded (i.e., certain opcodes have register identifiers, etc., while others are fairly straight-forward with a single identifier).</p> <p>Your finite state machine can basically do the following:</p> <ol> <li>Get the first nibble of the opcode using a mask like `0xF000. This will allow you to "categorize" the opcode</li> <li>Based on the function category from step 1, apply more masks to either get the register values from the opcode, or whatever other variables might be encoded with the opcode that will narrow down the actual function that would need to be called, as well as it's arguments.</li> <li>Once you have the opcode and the variable information, do a look-up into a fixed-length table of functions that have the appropriate handlers to coincide with the opcode functionality and the variables that go along with the opcode. While you can, in your state machine, hard-code the names of the functions that would go with each opcode once you've isolated the proper functionality, a table that you initialize with function-pointers for each opcode is a more flexible approach that will let you modify the code functionality easier (i.e., you could easily swap between debug handlers and "normal" handlers, etc.).</li> </ol>

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