Question
Design a MIPS processor supporting only the R-type and the jset rs, rt, rd instruction. The jset rs, rt, rd instruction does the following: If
Design a MIPS processor supporting only the R-type and the jset rs, rt, rd instruction. The jset rs, rt, rd instruction does the following:
If rs is not equal to rt, the next PC is the memory content at rs-rt and rd is set to be rs-rt; otherwise, the next PC is PC+4 and register $ra is set to be PC+4.
Recall that $ra is the special register used in the jal instruction.
For example,
- if rs and rt are 20 and 8 respectively, rd will be 12, and PC will be the memory content at 12.
- if rs and rt are 20 and 20 respectively, rd will not be changed, PC will be PC+4, and $ra will be PC+4.
For this problem, assume that the opcode of R-type is 000000 and the opcode of jset is 100000.
- (30 points) Show the data path of this processor, add 2-1 MUX when necessary. Besides a group of wires, please show clearly the indices of the bits.
- (20 points) Consider the control signals for the 2-1 MUX. Please fill in the table (you should not need more than 4 2-1 MUXes). In case of dont care, write down 0. Then write down the logic functions. Certain bits in the instruction can be denoted as, for example, ins[31]. The ALU zero output can be referred to simply as z.
| R-type | jset (rs != rt) | jset (rs == rt) |
MUXCtrl1 |
|
|
|
MUXCtrl2 |
|
|
|
MUXCtrl3 |
|
|
|
MUXCtrl4 |
|
|
|
Step by Step Solution
There are 3 Steps involved in it
Step: 1
Get Instant Access to Expert-Tailored Solutions
See step-by-step solutions with expert insights and AI powered tools for academic success
Step: 2
Step: 3
Ace Your Homework with AI
Get the answers you need in no time with our AI-driven, step-by-step assistance
Get Started