P3 is a single-cycle CPU drawn in logisim, with about 30 instructions.
P4 is a Verilog version of P3.
P5 is a basic pipeline CPU with about 10 instructions.
P6 with over 50 instructions .
P7 is a final version with some data exchange with device and error solutions.
You can coding in Mars, a MIPS interpreter, then generate instructions of your code, and run them in CPU.
MagicMars is a tool to show the MIPS interpreting result and you can compare it with output information in P4/P5/P6/P7.