mirror of https://github.com/trudnai/Steve2.git
49 lines
1.0 KiB
C
49 lines
1.0 KiB
C
//
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// main.c
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// 6502
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//
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// Created by Tamas Rudnai on 7/14/19.
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// Copyright © 2019 GameAlloy. All rights reserved.
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//
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#ifndef __6502_INSTR_MISC_H__
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#define __6502_INSTR_MISC_H__
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/**
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BRK Force Break
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interrupt, N Z C I D V
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push PC+2, push SR - - - 1 - -
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addressing assembler opc bytes cyles
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--------------------------------------------
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implied BRK 00 1 7
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**/
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INLINE void BRK() {
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dbgPrintf("BRK ");
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PUSH_addr(m6502.PC +1); // PC +2, however, fetch already incremented it by 1
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// B flag should be set before pushing flags onto the stack
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m6502.B = 1;
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PUSH(m6502.SR);
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m6502.I = 1;
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JMP(memread16(IRQ_VECTOR));
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}
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/**
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NOP No Operation
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--- N Z C I D V
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- - - - - -
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addressing assembler opc bytes cyles
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--------------------------------------------
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implied NOP EA 1 2
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**/
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INLINE void NOP() {
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dbgPrintf("NOP ");
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}
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#endif // __6502_INSTR_MISC_H__
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