8bitcpu/document.txt at main · HaydenD100/8bitcpu · GitHub

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#include
opcodes
0x0 MR reg, reg/8bit
0x1 LR reg, HL/16bit       load byte
0x2 WR reg, HL/16bit        write byte
0x3 ADD reg, reg/8bit
0x4 ADC reg, reg/8bit + c flag    resets c flag
0x5 SUB reg, reg/8bit
0x6 SBB reg, reg/8bit + b flag    resets b flag
0x7 JCN 4bitflag flag HL/Adress 1 bit, 001 = L 010 = C 011 100 = B, HL/16bit
0x8 CMP reg, reg/bit
0x9 PUSH reg/8bit
0xa POP reg
0xb AND reg, 8bit/reg
0xc OR reg, 8bit/reg
0xd NOR reg, 8bit/reg
0xe INB reg, PORT
0xf OUTB reg, PORT

REGISTERS
A 8bit
B 8bit
C 8bit
D 8bit
H 8bit //HL can store a 16 bit Address
L 8bit
Flag 8bit

SP 16bit
PC 16bit
IR 8bit


Flags
    LESS
    EQUAL
    CARRY
    BORROW


O = Opcode
R = Register
F = Flag for register or value/Address
OOOOFRRR


PORTS:
0x01 in/out char
0x02 status
0xf HALT


MACROS
RET             returns from sub routine by popping the return address off the stack
Call label      Goes to label pushes address onto stack