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toolic
toolic
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I have an assignment that requires me to build an 7-bit CPU. I’m done with implementing some of the requirements that includes 4 8-bit registers (the requirements say I have to store the parity bit), the ALU. I also added the Program Counter and the ROM for the instructions to be written into.

I have to now write the instructions (8 of them) into the ROM as hexadecimal and that’s where I’m confused. The way I’ve seen people do it is define the 16-bit instruction. I was planning on defining it as 1 bit to specify whether the instruction uses immediate values, opcodes (3 bits in my case), 2 for source register and 2 for destination register, and then 7 bits for if I have immediate values.

I understand how to write them into the ROM but how can I implement the logic to assign an opcode to a specific operation?

For example, lets say I have an instruction “MOV Rd, Rs”, how am I meant to write the instructions into the ROM without basically hardcoding the bits for the source and destination register.

I hope everything I said makes sense. I’m very new to all this so please help 😭.

I have an assignment that requires me to build an 7-bit CPU. I’m done with implementing some of the requirements that includes 4 8-bit registers (the requirements say I have to store the parity bit), the ALU. I also added the Program Counter and the ROM for the instructions to be written into.

I have to now write the instructions (8 of them) into the ROM as hexadecimal and that’s where I’m confused. The way I’ve seen people do it is define the 16-bit instruction. I was planning on defining it as 1 bit to specify whether the instruction uses immediate values, opcodes (3 bits in my case), 2 for source register and 2 for destination register, and then 7 bits for if I have immediate values.

I understand how to write them into the ROM but how can I implement the logic to assign an opcode to a specific operation?

For example, lets say I have an instruction “MOV Rd, Rs”, how am I meant to write the instructions into the ROM without basically hardcoding the bits for the source and destination register.

I hope everything I said makes sense. I’m very new to all this so please help 😭

I have an assignment that requires me to build an 7-bit CPU. I’m done with implementing some of the requirements that includes 4 8-bit registers (the requirements say I have to store the parity bit), the ALU. I also added the Program Counter and the ROM for the instructions to be written into.

I have to now write the instructions (8 of them) into the ROM as hexadecimal and that’s where I’m confused. The way I’ve seen people do it is define the 16-bit instruction. I was planning on defining it as 1 bit to specify whether the instruction uses immediate values, opcodes (3 bits in my case), 2 for source register and 2 for destination register, and then 7 bits for if I have immediate values.

I understand how to write them into the ROM but how can I implement the logic to assign an opcode to a specific operation?

For example, lets say I have an instruction “MOV Rd, Rs”, how am I meant to write the instructions into the ROM without basically hardcoding the bits for the source and destination register.

I hope everything I said makes sense. I’m very new to all this.

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maira
maira
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How to implement the Instruction Set in Logisim

I have an assignment that requires me to build an 7-bit CPU. I’m done with implementing some of the requirements that includes 4 8-bit registers (the requirements say I have to store the parity bit), the ALU. I also added the Program Counter and the ROM for the instructions to be written into.

I have to now write the instructions (8 of them) into the ROM as hexadecimal and that’s where I’m confused. The way I’ve seen people do it is define the 16-bit instruction. I was planning on defining it as 1 bit to specify whether the instruction uses immediate values, opcodes (3 bits in my case), 2 for source register and 2 for destination register, and then 7 bits for if I have immediate values.

I understand how to write them into the ROM but how can I implement the logic to assign an opcode to a specific operation?

For example, lets say I have an instruction “MOV Rd, Rs”, how am I meant to write the instructions into the ROM without basically hardcoding the bits for the source and destination register.

I hope everything I said makes sense. I’m very new to all this so please help 😭