V22.0436 - Prof. Grishman
Assignment 6: MIPS Control Unit
In this assignment you will use Logisim to build two separate circutis,
the main control and the ALU control for the MIPS processor covered in
class and described in sectiions 5.3 and 5.4. The hardware
designs are shown in Appendix C.
The ALU control should have as inputs (from top to bottom) a two-wire
bundle, ALUOp, and a 6-wire bundle, Func. Its output should
be a 4-wire bundle, ALUcon.
The main control unit should have as input the opcode, a 6-bit bundle,
Op. The outputs should be (from top to bottom): branch,
RegDst, MemRead, MemToReg, ALUOp, MemWrite, ALUSrc, and RegWrite. ALUOp
is a 2-wire bundle; the rest are all single wires.
For extra credit, add the
logic for the nor instruction to
the ALU control. Note that the logic in the book is carefully
optimized for the selected instructions, so adding nor may require some
redesign of the circuit, not just adding gates. For the extra
credit, it is not required that the design be as optimized as the
Due Thursday, November 6th.
Mail your homework (the .circ file) to firstname.lastname@example.org and to email@example.com (Mr. Yu-shun
Cheng) and mark
the mail CompArch -- Asgn 6.
If you have included the extra credit, say so in the mail.