7 Getting started

We realize that this project may seem very difficult, so we have provided a step-by-step guide on how to get started with it:

1. Read this document at least twice. It will probably make more sense the second time you read it.
2. Read and understand the example assembly language programs we have provided. You will need to become familiar with the Smalltium assembly language in order to write test programs.
3. Try writing a few simple assembly language programs and running them through the assembler. Take a look at the output of the assembler and see how it corresponds to the assembly language code. Review section 3 for general information about assembly language and section 5 for information about the individual instructions and assembly language examples.
4. Read and understand the code we have provided for the simulator (cpu.pas or cpu.cpp). We have already implemented three of the instructions and one of the traps for you, to give you an idea of how it is done.
5. Assemble hi.asm and run it in the simulator. It only uses the three instructions that we provided, so it should run correctly. Try writing another assembly program that only uses these instructions and run it in the simulator as well.
6. Now start implementing each of the instructions. Test each new instruction as you implement it and make sure that it works before moving on to the next one. Write a small assembly language program for each instruction that only uses the instructions you have implemented so far, and demonstrates that the new instruction works. We suggest implementing the instructions in the following order:
   1. The traps. You will need the traps in order to display the results in your debugging programs. Start with the output traps, then do the input traps (you can't really test the input without output).
   2. ADD, SUB, MULT, and DIV.
   3. LOAD and STORE.
   4. JMP and CMP. At this point, addnum.asm should work.
   5. LOADi and STOREi. At this point, hello.asm should work.
7. After you have the simulator working to this point, sit back and take a breather and congratulate yourself for getting this far. But you're not done yet! Now you get to exercise your creativity and show us how good you really are. The next section will tell you various things you can do to extend the Smalltium beyond these specifications.