2022-12-31 12:56:17 +01:00
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# Fox32 instructions
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2023-01-01 03:25:31 +01:00
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This file describes every fox32 instruction in detail. For a general
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2023-02-05 13:44:53 +01:00
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description of the fox32 CPU and instruction encoding details, see [cpu.md](./cpu.md).
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## Arithmetic instructions
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### ADD: add
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### SUB: subtract
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### INC: increment (add 1)
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### DEC: decrement (subtract 1)
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### CMP: compare
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### AND: bitwise AND
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### OR: bitwise OR
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### NOT: bitwise NOT
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### XOR: bitwise XOR
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### BSE: bit set
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### BCL: bit clear
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### BTS: test if bit set
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### SLA: shift left
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### SRA: shift right arithmetic (with sign extension)
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### SRL: shift right logical (with zero extension)
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### ROL: rotate left
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### ROR: rotate right
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### MUL: multiply (unsigned)
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### IMUL: multiply (signed)
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### DIV: divide (unsigned)
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### IDIV: divide (signed)
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### REM: calculate remainder of division (unsigned)
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### IREM: remainder (signed)
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### NOP: no operation
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### MOV: move value
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### MOVZ: move value and clear upper bits in target register
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### RTA: calculate address relative to instruction pointer
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## Stack instructions
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### PUSH: push value to stack
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### POP: pop value from stack
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## Control flow instructions
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### JMP: absolute jump
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### RJMP: relative jump
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### LOOP: absolute loop
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### RLOOP: relative loop
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### CALL: absolute call
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### RCALL: relative call
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### RET: return from function
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### RETI: return from interrupt
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### ISE: set interrupt enable flag
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### ICL: clear interrupt enable flag
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### BRK: debug breakpoint
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### INT: raise interrupt
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### HALT: halt CPU
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## MMU instructions
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### MSE: set MMU enable flag
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### MCL: clear MMU enable flag
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### FLP: flush page from TLB
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### TLB: flush TLB and set page directory pointer
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## I/O instructions
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### IN: get input from I/O bus
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### OUT: output on I/O bus
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