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encoding.md

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Encoding

size instr  off cond dest src <src>          <srcoff> <dest>         <dstoff>
xx   xxxxxx x   xxx  xx   xx  <8,16,32 bits> <8 bits> <8,16,32 bits> <8 bits>

Size table

If the instruction doesn't allow variable sizes or a size was not specified, set the size bits to Word (0b10)
0b00 byte (8 bits)
0b01 half (16 bits)
0b10 word (32 bits)

Instruction table

0x -0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -A -B -C -D -E -F
0- NOP ADD[.8,16,32] MUL[.8,16,32] AND[.8,16,32] SLA[.8,16,32] SRA[.8,16,32] BSE[.8,16,32] CMP[.8,16,32] JMP RJMP[.8,16,32] PUSH[.8,16,32] IN ISE MSE
1- HALT INC[.8,16,32] OR[.8,16,32] IMUL[.8,16,32] SRL[.8,16,32] BCL[.8,16,32] MOV[.8,16,32] CALL RCALL[.8,16,32] POP[.8,16,32] OUT ICL MCL
2- BRK SUB[.8,16,32] DIV[.8,16,32] XOR[.8,16,32] ROL[.8,16,32] ROR[.8,16,32] BTS[.8,16,32] MOVZ[.8,16,32] LOOP RLOOP[.8,16,32] RET INT TLB
3- DEC[.8,16,32] REM[.8,16,32] NOT[.8,16,32] IDIV[.8,16,32] IREM[.8,16,32] ICMP[.8,16,32] RTA[.8,16,32] RETI FLP

Condition table
0b000 --- always
0b001 IFZ zero
0b010 IFNZ not zero
0b011 IFC carry
0b011 IFLT less than (equivalent to IFC)
0b100 IFNC not carry
0b100 IFGTEQ greater than or equal to (equivalent to IFNC)
0b101 IFGT greater than
0b110 IFLTEQ less than or equal to

Source/Destination table
0b00 register
0b01 register (pointer)
0b10 immediate
0b11 immediate (pointer)
Using an immediate (0b10) as the destination type is only allowed in a few cases, such as with the OUT instruction. Using it with instructions where it doesn't make sense (such as doing mov 0, 1 for example) will throw an invalid opcode exception.

Register Pointer Offset

The off field indicates that each operand of type 0b01 (register pointer) has an 8-bit immediate following the operand. This immediate is added to the value of the register before dereferencing.