A few general procedures can be followed while building a new microprocessor or microcontroller unit to make the process run more rationally. These few stages can be broken down into smaller jobs that can be completed more quickly. The following are the general steps in creating a new microprocessor:
Determine The Feature Set
We must determine whether the machine will support many instructions or a limited number of instructions. More instructions complicate the design but simplify programming and use of the microprocessor. On the other hand, while having fewer instructions makes it easier to design, programming can be more difficult and costly. Make a list of the basic arithmetic operations you’d like your chip to support:
- Multiplication Division
- Shifting and Rotating Logical Operations: AND, OR, XOR, NOR, NOT, etc.
Make a list of your machine’s other capabilities:
- Unprecedented leaps
- Conditional Jumps (and under what circumstances?)
- Stack operations (push, pop) It’s much easier to set out the structure for our data flow once we know what our chip is meant to perform.
Create A Data Path
We need to figure out what ALU architecture our CPU will employ right away:
- All three options above
More than any other, this choice will have the greatest impact on the final design. Do not move forward with the design process until you’ve decided on this. You can then create your memory element and layout your ALU once you have your ALU architecture.
There are a few things we need to think about:
- Is this a RISC, CISC, or VLIW processor?
- What is the length of a machine word?
- What are your strategies for dealing with instant values?
- What are the types of instructions that can take instantaneous values?
- Are there any instructions that can be used to call and return a function?
We frequently need to determine whether our processor will be compatible with higher-level languages once we have our machine code foundations. In a RISC, determining the length of the instruction word is a critical issue that needs careful consideration.
After you’ve completed all of the preceding procedures, build the required logic to manage the data route, and your processor will be ready to use.
Visit our blog page to learn about the necessary steps to design a processor’s architecture.