ISA

CommaISA

Version: 0.0.1, 12|05|2023

New and improved, overhauled ISA:

Data Types:

• Byte: 8 bits
• Halfword: 16 bits
• Word: 32 bits

Registers:

• 16 general-purpose registers (R0-R15)
• 1 program counter (PC)
• 1 stack pointer (SP)

Instruction Set:

Load/Store Instructions:

• LD (Load): Load a value from memory to a register
• ST (Store): Store a value from a register to memory

Arithmetic Instructions:

• ADD: Add two values
• SUB: Subtract two values
• MUL: Multiply two values
• DIV: Divide two values

Logic Instructions:

• AND: Bitwise AND two values
• OR: Bitwise OR two values
• XOR: Bitwise XOR two values

Control Flow Instructions:

• JMP (Jump): Unconditional jump to a label
• JEQ (Jump if Equal): Jump to a label if two values are equal
• JNE (Jump if Not Equal): Jump to a label if two values are not equal
• JGT (Jump if Greater Than): Jump to a label if the first value is greater than the second value
• JLT (Jump if Less Than): Jump to a label if the first value is less than the second value
• CALL: Call a subroutine
• RET (Return): Return from a subroutine

Input/Output Instructions:

• IN: Read a byte from an input port
• OUT: Write a byte to an output port

Video Processing Instructions:

• LOADVID (Load Video): Load a video frame from memory to a video processing hardware
• DRAW (Draw): Draw an image to the video processing hardware
• SYNC (Synchronize): Synchronize the video processing hardware with the CPU

Expansion Instructions:

• NOP (No Operation): Do nothing
• HALT: Stop the CPU