Chip-8 Memory Map - RCA CDP18S711 Instruction Manual

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CHIP-8 Memory Map

RCA COSMAC VIP Instruction Manual
CDP1802 Register Use for CHIP-8
Interpreter
R0 = DMA pointer (page 0X for display refresh)
R1 = INTERRUPT routine program counter
R2 = Stack pointer
R3 = INTERPRETER subroutine program counter
R4 = CALL subroutine program counter
R5 = CHIP-8 instruction program counter
R6 = VX pointer (R6.1 must not be changed)
R7 = VY pointer (available for machine-language subroutines)
R8 = Timers (R8.1 = timer, R8.0 = tone duration)
R9 = Random number (+1 in INTERRUPT routine)
RA = I pointer
RB = Display page pointer (RB.1 = 0X)
RC =Available
RD = Available
RE = Available
RF = Available