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Added few undocumented instructions

This commit is contained in:
tudnai 2020-06-05 23:20:32 -07:00
parent 71348d606d
commit 16aa7a8d69
8 changed files with 238 additions and 69 deletions
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6
A2Mac.xcodeproj/project.pbxproj
View File

@ -13,6 +13,7 @@
323D042E248980600086A901 /* Preferences.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 323D042D248980600086A901 /* Preferences.storyboard */; };
323D043024898AB70086A901 /* PreferencesViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 323D042F24898AB70086A901 /* PreferencesViewController.swift */; };
323D04332489BFD80086A901 /* PreferencesWindowController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 323D04312489BFD80086A901 /* PreferencesWindowController.swift */; };
323D0437248B6BEA0086A901 /* 6502.c in Sources */ = {isa = PBXBuildFile; fileRef = 32439F7422ECD8AD0077AAE0 /* 6502.c */; };
323E2DCE245531E600156805 /* Apple2e_Enhanced.rom in Resources */ = {isa = PBXBuildFile; fileRef = 323E2DCC245531E500156805 /* Apple2e_Enhanced.rom */; };
323E2DCF245531E600156805 /* Apple2e_Enhanced.rom in Resources */ = {isa = PBXBuildFile; fileRef = 323E2DCC245531E500156805 /* Apple2e_Enhanced.rom */; };
323E2DD0245531E600156805 /* Apple2e.rom in Resources */ = {isa = PBXBuildFile; fileRef = 323E2DCD245531E500156805 /* Apple2e.rom */; };
@ -30,7 +31,6 @@
32440B80247CB66C000F9DA1 /* Merlin Assembler (early version, 40-column, DOS 3.3) side A.woz in Resources */ = {isa = PBXBuildFile; fileRef = 32440B7E247CB66C000F9DA1 /* Merlin Assembler (early version, 40-column, DOS 3.3) side A.woz */; };
32440B81247CB66C000F9DA1 /* Merlin Assembler (early version, 40-column, DOS 3.3) side B.woz in Resources */ = {isa = PBXBuildFile; fileRef = 32440B7F247CB66C000F9DA1 /* Merlin Assembler (early version, 40-column, DOS 3.3) side B.woz */; };
32440B83247CC4C0000F9DA1 /* Wavy Navy (4am crack).woz in Resources */ = {isa = PBXBuildFile; fileRef = 32440B82247CC4C0000F9DA1 /* Wavy Navy (4am crack).woz */; };
32440B84247E27D3000F9DA1 /* 6502.c in Sources */ = {isa = PBXBuildFile; fileRef = 32439F7422ECD8AD0077AAE0 /* 6502.c */; };
32440B85247E27D7000F9DA1 /* 6502.c in Sources */ = {isa = PBXBuildFile; fileRef = 32439F7422ECD8AD0077AAE0 /* 6502.c */; };
32440B8F247F86D6000F9DA1 /* Apple II+ Dealer Diagnostics.woz in Resources */ = {isa = PBXBuildFile; fileRef = 32440B86247F86D4000F9DA1 /* Apple II+ Dealer Diagnostics.woz */; };
32440B90247F86D6000F9DA1 /* XPS Diagnostic IIe 1.0.5.woz in Resources */ = {isa = PBXBuildFile; fileRef = 32440B87247F86D5000F9DA1 /* XPS Diagnostic IIe 1.0.5.woz */; };
@ -154,6 +154,7 @@
323D042D248980600086A901 /* Preferences.storyboard */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; path = Preferences.storyboard; sourceTree = "<group>"; };
323D042F24898AB70086A901 /* PreferencesViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PreferencesViewController.swift; sourceTree = "<group>"; };
323D04312489BFD80086A901 /* PreferencesWindowController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PreferencesWindowController.swift; sourceTree = "<group>"; };
323D0435248B20F20086A901 /* 6502_instr_undoc.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = 6502_instr_undoc.h; sourceTree = "<group>"; };
323E2DCC245531E500156805 /* Apple2e_Enhanced.rom */ = {isa = PBXFileReference; lastKnownFileType = file; path = Apple2e_Enhanced.rom; sourceTree = "<group>"; };
323E2DCD245531E500156805 /* Apple2e.rom */ = {isa = PBXFileReference; lastKnownFileType = file; path = Apple2e.rom; sourceTree = "<group>"; };
32439F7222ECD8AC0077AAE0 /* A2Mac-Bridging-Header.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "A2Mac-Bridging-Header.h"; sourceTree = "<group>"; };
@ -338,6 +339,7 @@
32439F7622ECD8AD0077AAE0 /* 6502_instr_set_clr.h */,
32439F7722ECD8AD0077AAE0 /* 6502_instr_stack.h */,
32439F7822ECD8AD0077AAE0 /* 6502_instr_logic.h */,
323D0435248B20F20086A901 /* 6502_instr_undoc.h */,
32439F7922ECD8AD0077AAE0 /* 6502_instr_shift_rotate.h */,
32439F7A22ECD8AD0077AAE0 /* 6502_instr_inc_dec.h */,
32439F7B22ECD8AD0077AAE0 /* 6502_instr_compare_test.h */,
@ -970,12 +972,12 @@
files = (
325EB63623F8F78300C6B4A4 /* disk.c in Sources */,
325EB63923F9E48100C6B4A4 /* common.c in Sources */,
323D0437248B6BEA0086A901 /* 6502.c in Sources */,
32A9F74A2467B60B004902A1 /* speaker.c in Sources */,
32BFFB5D22EACC630003B53F /* ViewController.swift in Sources */,
325EB69323FE6C6200C6B4A4 /* HiRes.swift in Sources */,
32C4532E233345430000EBA1 /* MonitorView.swift in Sources */,
32440BA32480D5C0000F9DA1 /* LoRes.swift in Sources */,
32440B84247E27D3000F9DA1 /* 6502.c in Sources */,
325EB62F23F8856F00C6B4A4 /* woz.c in Sources */,
323D04332489BFD80086A901 /* PreferencesWindowController.swift in Sources */,
32BFFB5B22EACC630003B53F /* AppDelegate.swift in Sources */,

90
src/cpu/6502.c
View File

@ -405,105 +405,105 @@ INLINE int m6502_Step() {
switch ( fetch() ) {
case 0x00: BRK(); return 7; // BRK
case 0x01: ORA( src_X_ind() ); return 6; // ORA X,ind
// case 0x02: // t jams
// case 0x03: // SLO* (undocumented)
// case 0x04: // NOP* (undocumented)
case 0x02: KIL(); return 0; // KIL - Hangs the CPU // t jams
case 0x03: SLO( addr_zp_X() ); return 8; // SLO* zpg,X (undocumented)
case 0x04: NOP2( src_zp() ); return 3; // NOP* zpg (undocumented)
case 0x05: ORA( src_zp() ); return 3; // ORA zpg
case 0x06: ASL( addr_zp() ); return 5; // ASL zpg
// case 0x07: // SLO* (undocumented)
case 0x07: SLO( addr_zp() ); return 5; // SLO* zpg (undocumented)
case 0x08: PHP(); return 3; // PHP
case 0x09: ORA( imm() ); return 2; // ORA imm
case 0x0A: ASLA(); return 2; // ASL A
// case 0x0B: // ANC** (undocumented)
// case 0x0C: // NOP* (undocumented)
case 0x0B: ANC( imm() ); return 2; // ANC** imm (undocumented)
case 0x0C: NOP2( src_abs() ); return 4; // NOP* (undocumented)
case 0x0D: ORA( src_abs() ); return 4; // ORA abs
case 0x0E: ASL( addr_abs() ); return 6; // ASL abs
// case 0x0F: // SLO* (undocumented)
case 0x0F: SLO( addr_abs() ); return 6; // SLO* (undocumented)
case 0x10: BPL( rel_addr() ); return 3; // BPL rel
case 0x11: ORA( src_ind_Y() ); return 5; // ORA ind,Y
// case 0x12: // t jams
// case 0x13: // SLO* (undocumented)
// case 0x14: // NOP* (undocumented)
case 0x12: KIL(); return 0; // KIL - Hangs the CPU // t jams
case 0x13: SLO( addr_zp_Y() ); return 8; // SLO* zpg,Y (undocumented)
case 0x14: NOP2( addr_zp_X() ); return 4; // NOP* zpg,X (undocumented)
case 0x15: ORA( src_zp_X() ); return 4; // ORA zpg,X
case 0x16: ASL( addr_zp_X() ); return 6; // ASL zpg,X
// case 0x17: // SLO* (undocumented)
case 0x17: SLO( addr_zp_X() ); return 6; // SLO* zpg,X (undocumented)
case 0x18: CLC(); return 2; // CLC
case 0x19: ORA( src_abs_Y() ); return 4; // ORA abs,Y
// case 0x1A: // NOP* (undocumented)
// case 0x1B: // SLO* (undocumented)
// case 0x1C: // NOP* (undocumented)
case 0x1A: NOP(); return 2; // NOP* (undocumented)
case 0x1B: SLO( addr_abs_Y() ); return 7; // SLO* abs,Y (undocumented)
case 0x1C: NOP2( src_abs_X() ); return 4; // NOP* (undocumented)
case 0x1D: ORA( src_abs_X() ); return 4; // ORA abs,X
case 0x1E: ASL( addr_abs_X() ); return 7; // ASL abs,X
// case 0x1F: // SLO* (undocumented)
case 0x1F: SLO( addr_abs_X() ); return 7; // SLO* abs,X (undocumented)
case 0x20: JSR( abs_addr() ); return 6; // JSR abs
case 0x21: AND( src_X_ind() ); return 6; // AND X,ind
// case 0x22: KIL
// case 0x23: RLA izx 8
case 0x22: KIL(); return 0; // KIL - Hangs the CPU
case 0x23: RLA( addr_ind_X() ); return 8; // RLA* ind,X 8 (undocumented)
case 0x24: BIT( src_zp() ); return 3; // BIT zpg
case 0x25: AND( src_zp() ); return 3; // AND zpg
case 0x26: ROL( addr_zp() ); return 5; // ROL zpg
// case 0x27: RLA zp 5
case 0x27: RLA( addr_zp() ); return 5; // RLA* zpg 5 (undocumented)
case 0x28: PLP(); return 4; // PLP
case 0x29: AND( imm() ); return 2; // AND imm
case 0x2A: ROLA(); return 2; // ROL A
// case 0x2B: ANC imm 2
case 0x2B: ANC( imm() ); return 2; // ANC* imm 2 (undocumented)
case 0x2C: BIT( src_abs() ); return 4; // BIT abs
case 0x2D: AND( src_abs() ); return 4; // AND abs
case 0x2E: ROL( addr_abs() ); return 6; // ROL abs
// case 0x2F: RLA abs 6
case 0x2F: RLA( addr_abs() ); return 6; // RLA* abs 6 (undocumented)
case 0x30: BMI( rel_addr() ); return 3; // BMI rel
case 0x31: AND( src_ind_Y() ); return 5; // AND ind,Y
// case 0x32: KIL
// case 0x33: RLA izy 8
// case 0x34: NOP zpx 4
case 0x32: KIL(); return 0; // KIL - Hangs the CPU
case 0x33: RLA( addr_ind_Y() ); return 8; // RLA* izy 8 (undocumented)
case 0x34: NOP2( src_zp_X() ); return 4; // NOP* zpx 4 (undocumented)
case 0x35: AND( src_zp_X() ); return 4; // AND zpg,X
case 0x36: ROL( addr_zp_X() ); return 6; // ROL zpg,X
// case 0x37: RLA zpx 6
case 0x37: RLA( addr_zp_X() ); return 6; // RLA* zpx 6 (undocumented)
case 0x38: SEC(); return 2; // SEC
case 0x39: AND( src_abs_Y() ); return 4; // AND abs,Y
// case 0x3A: NOP 2
// case 0x3B: RLA aby 7
// case 0x3C: NOP abx 4
case 0x3A: NOP(); return 2; // NOP* 2 (undocumented)
case 0x3B: RLA( addr_abs_Y() ); return 7; // RLA* aby 7 (undocumented)
case 0x3C: NOP2( src_abs_X() ); return 4; // NOP* abx 4 (undocumented)
case 0x3D: AND( src_abs_X() ); return 4; // AND abs,X
case 0x3E: ROL( addr_abs_X() ); return 7; // ROL abs,X
// case 0x3F: RLA abx 7
case 0x3F: RLA( addr_abs_X() ); return 7; // RLA* abx 7 (undocumented)
case 0x40: RTI(); return 6; // RTI
case 0x41: EOR( src_X_ind() ); return 6; // EOR X,ind
// case 0x42: KIL
// case 0x43: SRE izx 8
// case 0x44: NOP zp 3
case 0x42: KIL(); return 0; // KIL - Hangs the CPU
case 0x43: SRE( addr_ind_X() ); return 8; // SRE* izx 8 (undocumented)
case 0x44: NOP(); return 3; // NOP* zp 3 (undocumented)
case 0x45: EOR( src_zp() ); return 3; // EOR zpg
case 0x46: LSR( addr_zp() ); return 5; // LSR zpg
// case 0x47: SRE zp 5
case 0x47: SRE( addr_zp() ); return 5; // SRE* zp 5 (undocumented)
case 0x48: PHA(); return 3; // PHA
case 0x49: EOR( imm() ); return 2; // EOR imm
case 0x4A: LSRA(); return 2; // LSR A
// case 0x4B: ALR imm 2
case 0x4B: ASR( imm() ); return 2; // ASR* imm 2 (undocumented)
case 0x4C: JMP( abs_addr() ); return 3; // JMP abs
case 0x4D: EOR( src_abs() ); return 4; // EOR abs
case 0x4E: LSR( addr_abs() ); return 6; // LSR abs
// case 0x4F: SRE abs 6
case 0x4F: SRE( abs_addr() ); return 6; // SRE* abs 6 (undocumented)
case 0x50: BVC( rel_addr() ); return 3; // BVC rel
case 0x51: EOR( src_ind_Y() ); return 5; // EOR ind,Y
// case 0x52: KIL
// case 0x53: SRE izy 8
// case 0x54: NOP zpx 4
case 0x52: KIL(); return 0; // KIL - Hangs the CPU
case 0x53: SRE( addr_ind_Y() ); return 8; // SRE* izy 8 (undocumented)
case 0x54: NOP2( src_zp_X() ); return 4; // NOP* zpx 4 (undocumented)
case 0x55: EOR( src_zp_X() ); return 4; // AND zpg,X
case 0x56: LSR( addr_zp_X() ); return 6; // LSR zpg,X
// case 0x57: SRE zpx 6
case 0x57: SRE( addr_ind_X() ); return 6; // SRE* zpx 6 (undocumented)
case 0x58: CLI(); return 2; // CLI
case 0x59: EOR( src_abs_Y() ); return 4; // EOR abs,Y
// case 0x5A: NOP 2
// case 0x5B: SRE aby 7
// case 0x5C: NOP abx 4
case 0x5A: NOP(); return 2; // NOP* 2 (undocumented)
case 0x5B: SRE( addr_abs_Y() ); return 7; // SRE* aby 7 (undocumented)
case 0x5C: NOP2( src_abs_X() ); return 4; // NOP* abx 4 (undocumented)
case 0x5D: EOR( src_abs_X() ); return 4; // EOR abs,X
case 0x5E: LSR( addr_abs_X() ); return 7; // LSR abs,X
// case 0x5F: SRE abx 7
case 0x5F: SRE( addr_abs_X() ); return 7; // SRE* abx 7 (undocumented)
case 0x60: RTS(); return 6; // RTS
case 0x61: ADC( src_X_ind() ); return 6; // ADC X,ind
// case 0x62: KIL
case 0x62: KIL(); return 0; // KIL - Hangs the CPU
// case 0x63: RRA izx 8
// case 0x64: NOP zp 3
case 0x64: NOP(); return 3; // NOP* zp 3 (undocumented)
case 0x65: ADC( src_zp() ); return 3; // ADC zpg
case 0x66: ROR( addr_zp() ); return 5; // ROR zpg
// case 0x67: RRA zp 5
@ -532,7 +532,7 @@ INLINE int m6502_Step() {
case 0x7E: ROR( addr_abs_X() ); return 7; // ROR abs,X
// case 0x7F:
// case 0x80:
case 0x81: STA( addr_X_ind() ) ; return 6; // STA X,ind
case 0x81: STA( addr_ind_X() ) ; return 6; // STA X,ind
// case 0x82:
// case 0x83:
case 0x84: STY( addr_zp() ); return 3; // STY zpg

4
src/cpu/6502_vanilla.c
View File

@ -41,6 +41,8 @@ unsigned long long MHz_6502 = default_MHz_6502;
unsigned long long clk_6502_per_frm = default_MHz_6502 / fps;
unsigned long long clk_6502_per_frm_set = default_MHz_6502 / fps;
unsigned long long clk_6502_per_frm_max = 0;
unsigned long long clk_6502_per_frm_max_sound = 4 * default_MHz_6502 / fps;
unsigned long long tick_per_sec = G;
@ -531,7 +533,7 @@ INLINE int m6502_Step() {
case 0x7E: ROR( addr_abs_X() ); return 7; // ROR abs,X
// case 0x7F:
// case 0x80:
case 0x81: STA( addr_X_ind() ) ; return 6; // STA X,ind
case 0x81: STA( addr_ind_X() ) ; return 6; // STA X,ind
// case 0x82:
// case 0x83:
case 0x84: STY( addr_zp() ); return 3; // STY zpg

39
src/cpu/instructions/6502_instr_arithmetic.h
View File

@ -29,15 +29,12 @@
(indirect,X) ADC (oper,X) 61 2 6
(indirect),Y ADC (oper),Y 71 2 5*
**/
INLINE void ADC( uint8_t src ) {
dbgPrintf("ADC(%02X) ", src);
disPrintf(disassembly.inst, "ADC");
INLINE void _ADC( uint8_t src ) {
uint16_t tmp;
// V = C7 != C6
m6502.V = ((m6502.A & 0x7F) + (src & 0x7F) + (m6502.C != 0)) > 0x7F;
if ( m6502.D ) {
if ( (tmp = (m6502.A & 0x0F) + (src & 0x0F) + (m6502.C != 0)) > 0x09 ) {
tmp += 0x06;
@ -53,19 +50,25 @@ INLINE void ADC( uint8_t src ) {
set_flags_NZ( m6502.A = tmp );
m6502.C = tmp > 0xFF;
m6502.V ^= m6502.C;
// // this is good but slow:
// uint16_t tmp = (uint16_t)m6502.A + src + m6502.C;
// m6502.V = ( !((m6502.A ^ src) & 0x80)) && ( (m6502.A ^ tmp) & 0x80);
// m6502.C = tmp > 0xFF;
// set_flags_NZ( m6502.A = tmp );
// // this is good but slow:
// uint16_t tmp = (uint16_t)m6502.A + src + m6502.C;
// m6502.V = ( ((m6502.A ^ src) ^ (m6502.A ^ tmp)) & 0x80 ) != 0;
// m6502.C = tmp > 0xFF;
// set_flags_NZ( m6502.A = tmp );
// // this is good but slow:
// uint16_t tmp = (uint16_t)m6502.A + src + m6502.C;
// m6502.V = ( !((m6502.A ^ src) & 0x80)) && ( (m6502.A ^ tmp) & 0x80);
// m6502.C = tmp > 0xFF;
// set_flags_NZ( m6502.A = tmp );
// // this is good but slow:
// uint16_t tmp = (uint16_t)m6502.A + src + m6502.C;
// m6502.V = ( ((m6502.A ^ src) ^ (m6502.A ^ tmp)) & 0x80 ) != 0;
// m6502.C = tmp > 0xFF;
// set_flags_NZ( m6502.A = tmp );
}
INLINE void ADC( uint8_t src ) {
dbgPrintf("ADC(%02X) ", src);
disPrintf(disassembly.inst, "ADC");
_ADC(src);
}
/**

16
src/cpu/instructions/6502_instr_misc.h
View File

@ -33,6 +33,22 @@ INLINE int BRK() {
return 7;
}
/**
KIL Kills the CPU - Well, it hangs it untill the next power cycle
**/
INLINE int KIL() {
dbgPrintf("KIL ");
disPrintf(disassembly.inst, "KIL");
PUSH_addr(m6502.PC -1); // PC, however, fetch already incremented it by 1
// B flag should be set before pushing flags onto the stack
m6502.B = 1;
PUSH( getFlags().SR );
m6502.I = 1;
m6502.PC = memread16(IRQ_VECTOR);
return 7;
}
/**
NOP No Operation

9
src/cpu/instructions/6502_instr_shift_rotate.h
View File

@ -109,14 +109,17 @@ INLINE void ROLA() {
absolute ROR oper 6E 3 6
absolute,X ROR oper,X 7E 3 7
**/
INLINE void ROR( uint16_t addr ) {
dbgPrintf("ROR ");
disPrintf(disassembly.inst, "ROR");
INLINE void _ROR( uint16_t addr ) {
uint8_t C = m6502.C != 0;
m6502.C = WRLOMEM[addr] & 1;
WRLOMEM[addr] >>= 1;
set_flags_NZ( WRLOMEM[addr] |= C << 7 );
}
INLINE void ROR( uint16_t addr ) {
dbgPrintf("ROR ");
disPrintf(disassembly.inst, "ROR");
_ROR(addr);
}
INLINE void RORA() {
dbgPrintf("ROR ");
disPrintf(disassembly.inst, "ROR");

142
src/cpu/instructions/6502_instr_undoc.h Normal file
View File

@ -0,0 +1,142 @@
//
// main.c
// 6502
//
// Created by Tamas Rudnai on 7/14/19.
// Copyright © 2019 GameAlloy. All rights reserved.
//
#ifndef __6502_INSTR_UNDOC_H__
#define __6502_INSTR_UNDOC_H__
/**
ANC - "AND" Memory with Accumulator
THEN Copy Bit 7 of Result into Carry
(M "AND" A) -> A
THEN msb(A) -> C
**/
INLINE void ANC ( uint8_t src ) {
disPrintf(disassembly.inst, "ANC");
set_flags_NZ( m6502.A &= src );
m6502.C = m6502.A >> 7;
}
/**
ASR - "AND" Memory with Accumulator
THEN Shift Accumulator One Bit Right
(M "AND" A) -> A
THEN LSR A
**/
INLINE void ASR ( uint8_t src ) {
disPrintf(disassembly.inst, "ASR");
// AND
m6502.A &= src;
// LSR A
m6502.C = m6502.A & 1;
set_flags_NZ( m6502.A >>= 1 );
}
/**
NOP No Operation
--- N Z C I D V
- - - - - -
addressing assembler opc bytes cyles
--------------------------------------------
implied NOP EA ? ?
**/
INLINE void NOP2( uint8_t src ) {
disPrintf(disassembly.inst, "NOP2");
}
/**
RLA - Rotate Memory One Bit Left
THEN "AND" Memory with Accumulator
ROL M
AND M
**/
INLINE void RLA ( uint16_t addr ) {
disPrintf(disassembly.inst, "RLA");
// ROL M
uint8_t C = m6502.C != 0;
m6502.C = WRLOMEM[addr] & 0x80;
WRLOMEM[addr] <<= 1;
WRLOMEM[addr] |= C;
// AND M
set_flags_NZ( m6502.A &= WRLOMEM[addr] );
}
/**
RRA - Rotate Memory One Bit Right
THEN Add Memory to Accumulator with Carry
ROR M
ADC M
**/
INLINE void RRA ( uint16_t addr ) {
disPrintf(disassembly.inst, "RRA");
_ROR(addr);
_ADC(WRLOMEM[addr]);
}
/**
SLO - Shift Memory One Bit Left
THEN "OR" Memory with Accumulator
into Accumulator and Memory
ASL M
ORA M
-> A,M
**/
INLINE void SLO ( uint16_t addr ) {
disPrintf(disassembly.inst, "SLO");
m6502.C = WRLOMEM[addr] & 0x80;
WRLOMEM[addr] <<= 1; // ASL M -> M
m6502.A ^= WRLOMEM[addr]; // EOR M -> A
set_flags_NZ( WRLOMEM[addr] = m6502.A ); // A -> M
}
/**
SRE - Shift Memory One Bit Right
THEN "OR" Memory with Accumulator
LSR M
ORA M
**/
INLINE void SRE ( uint16_t addr ) {
disPrintf(disassembly.inst, "SRE");
// LSR
m6502.C = WRLOMEM[addr] & 1;
set_flags_NZ( WRLOMEM[addr] >>= 1 );
// EOR M
set_flags_NZ( m6502.A |= WRLOMEM[addr] );
}
#endif // __6502_INSTR_UNDOC_H__

1
src/cpu/instructions/6502_instructions.h
View File

@ -22,6 +22,7 @@
#include "6502_instr_call_ret_jump.h"
#include "6502_instr_set_clr.h"
#include "6502_instr_misc.h"
#include "6502_instr_undoc.h"
#endif // __6502_INSTRUCTIONS_H__