1534 lines
48 KiB
ArmAsm
1534 lines
48 KiB
ArmAsm
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.syntax unified
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.cpu cortex-m4
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.fpu softvfp
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.thumb
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.include "6502mac_gcc.S"
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.extern NES_RAM
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.extern NES_SRAM
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.extern spr_ram
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.extern debug_6502 // 无效操作码时调用这个函数
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.global cpunmi // cpu中断标志
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.global cpuirq // cpu中断标志
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.global clocks // apu要的cpu时钟
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.global cpu_data // 地址 cart.s
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.global NMI6502
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.global CPU_reset
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.global run6502
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.global op_table
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.equ IRQ_VECTOR, 0xfffe // IRQ / BRK中断向量地址
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.equ RES_VECTOR, 0xfffc // 复位中断向量地址
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.equ NMI_VECTOR, 0xfffa // NMI中断向量地址
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.section .text
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// BRK
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_00:
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ldr r0,[globalptr,#lastbank] // 6502PC从 ROM的最后偏移量
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sub r1,m6502_pc,r0
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add r0,r1,#1
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push16 // save PC
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encodeP (B+R) // save P
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ldr r12,=IRQ_VECTOR
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bl VecCont
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fetch 7
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@ LTORG // 把常量放在这里
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// ----------------------------------------------------------------------------
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_01:// ORA ($nn,X)
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// ----------------------------------------------------------------------------
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doIIX
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opORA
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fetch 6
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// ----------------------------------------------------------------------------
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_05:// ORA $nn
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// ----------------------------------------------------------------------------
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doZ
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opORA
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fetch 3
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// ----------------------------------------------------------------------------
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_06:// ASL $nn
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// ----------------------------------------------------------------------------
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doZ
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opASL
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fetch_c 5
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// ----------------------------------------------------------------------------
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_08:// PHP
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// ----------------------------------------------------------------------------
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encodeP (B+R)
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push8 r0
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fetch 3
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// ----------------------------------------------------------------------------
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_09:// ORA #$nn
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// ----------------------------------------------------------------------------
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doIMM
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opORA
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fetch 2
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// ----------------------------------------------------------------------------
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_0A:// ASL
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// ----------------------------------------------------------------------------
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adds m6502_a,m6502_a,m6502_a
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mov m6502_nz,m6502_a,asr#24 // NZ
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orr cycles,cycles,#CYC_C // Prepare C
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fetch_c 2 // also subs carry
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// ----------------------------------------------------------------------------
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_0D:// ORA $nnnn
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// ----------------------------------------------------------------------------
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doABS
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opORA
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fetch 4
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// ----------------------------------------------------------------------------
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_0E:// ASL $nnnn
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// ----------------------------------------------------------------------------
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doABS
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opASL
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fetch_c 6
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// ----------------------------------------------------------------------------
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_10:// BPL *
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// ----------------------------------------------------------------------------
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tst m6502_nz,#0x80000000
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ldrsb r0,[m6502_pc],#1
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IT EQ
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addeq m6502_pc,m6502_pc,r0
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IT EQ
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subeq cycles,cycles,#256
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fetch 2
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// ----------------------------------------------------------------------------
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_11:// ORA ($nn),Y
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// ----------------------------------------------------------------------------
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doIIY
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opORA
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fetch 5
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// ----------------------------------------------------------------------------
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_15:// ORA $nn,X
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// ----------------------------------------------------------------------------
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doZIXf
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opORA
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fetch 4
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// ----------------------------------------------------------------------------
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_16:// ASL $nn,X
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// ----------------------------------------------------------------------------
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doZIXf
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opASL
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fetch_c 6
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// ----------------------------------------------------------------------------
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_18:// CLC
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// ----------------------------------------------------------------------------
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bic cycles,cycles,#CYC_C
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fetch 2
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// ----------------------------------------------------------------------------
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_19:// ORA $nnnn,Y
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// ----------------------------------------------------------------------------
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doAIY
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opORA
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fetch 4
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// ----------------------------------------------------------------------------
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_1D:// ORA $nnnn,X
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// ----------------------------------------------------------------------------
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doAIX
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opORA
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fetch 4
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// ----------------------------------------------------------------------------
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_1E:// ASL $nnnn,X
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// ----------------------------------------------------------------------------
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doAIX
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opASL
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fetch_c 7
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// ----------------------------------------------------------------------------
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_20:// JSR $nnnn
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// ----------------------------------------------------------------------------
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ldrb r2,[m6502_pc],#1
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ldr r1,[globalptr,#lastbank]
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sub r0,m6502_pc,r1
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ldrb r1,[m6502_pc]
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orr m6502_pc,r2,r1,lsl#8
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push16
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encodePC
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fetch 6
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// ----------------------------------------------------------------------------
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_21:// AND ($nn,X)
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// ----------------------------------------------------------------------------
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doIIX
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opAND
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fetch 6
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// ----------------------------------------------------------------------------
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_24:// BIT $nn
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// ----------------------------------------------------------------------------
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doZ
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opBIT
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fetch 3
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// ----------------------------------------------------------------------------
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_25:// AND $nn
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// ----------------------------------------------------------------------------
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doZ
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opAND
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fetch 3
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// ----------------------------------------------------------------------------
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_26:// ROL $nn
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// ----------------------------------------------------------------------------
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doZ
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opROL
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fetch 5
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// ----------------------------------------------------------------------------
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_28:// PLP
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// ----------------------------------------------------------------------------
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pop8 r0
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decodeP
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fetch 4
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// ----------------------------------------------------------------------------
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_29:// AND #$nn
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// ----------------------------------------------------------------------------
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doIMM
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opAND
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fetch 2
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// ----------------------------------------------------------------------------
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_2A:// ROL
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// ----------------------------------------------------------------------------
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movs cycles,cycles,lsr#1 // get C
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IT CS
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orrcs m6502_a,m6502_a,#0x00800000
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adds m6502_a,m6502_a,m6502_a
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mov m6502_nz,m6502_a,asr#24 // NZ
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adc cycles,cycles,cycles // Set C
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fetch 2
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// ----------------------------------------------------------------------------
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_2C:// BIT $nnnn
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// ----------------------------------------------------------------------------
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doABS
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opBIT
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fetch 4
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// ----------------------------------------------------------------------------
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_2D:// AND $nnnn
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// ----------------------------------------------------------------------------
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doABS
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opAND
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fetch 4
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// ----------------------------------------------------------------------------
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_2E:// ROL $nnnn
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// ----------------------------------------------------------------------------
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doABS
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opROL
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fetch 6
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// ----------------------------------------------------------------------------
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_30:// BMI *
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// ----------------------------------------------------------------------------
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tst m6502_nz,#0x80000000
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ldrsb r0,[m6502_pc],#1
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IT NE
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addne m6502_pc,m6502_pc,r0
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IT NE
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subne cycles,cycles,#256
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fetch 2
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// ----------------------------------------------------------------------------
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_31:// AND ($nn),Y
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// ----------------------------------------------------------------------------
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doIIY
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opAND
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fetch 5
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// ----------------------------------------------------------------------------
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_35:// AND $nn,X
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// ----------------------------------------------------------------------------
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doZIXf
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opAND
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fetch 4
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// ----------------------------------------------------------------------------
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_36:// ROL $nn,X
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// ----------------------------------------------------------------------------
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doZIXf
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opROL
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fetch 6
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// ----------------------------------------------------------------------------
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_38:// SEC
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// ----------------------------------------------------------------------------
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orr cycles,cycles,#CYC_C
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fetch 2
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// ----------------------------------------------------------------------------
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_39:// AND $nnnn,Y
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// ----------------------------------------------------------------------------
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doAIY
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opAND
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fetch 4
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// ----------------------------------------------------------------------------
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_3D:// AND $nnnn,X
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// ----------------------------------------------------------------------------
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doAIX
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opAND
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fetch 4
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// ----------------------------------------------------------------------------
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_3E:// ROL $nnnn,X
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// ----------------------------------------------------------------------------
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doAIX
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opROL
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fetch 7
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// ----------------------------------------------------------------------------
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_40:// RTI
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// ----------------------------------------------------------------------------
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pop8 r0 // pop 6502 flags and decode
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decodeP
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pop16 // pop the return address
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encodePC
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fetch 6
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// ----------------------------------------------------------------------------
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_41:// EOR ($nn,X)
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// ----------------------------------------------------------------------------
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doIIX
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opEOR
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fetch 6
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// ----------------------------------------------------------------------------
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_45:// EOR $nn
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// ----------------------------------------------------------------------------
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doZ
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opEOR
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fetch 3
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// ----------------------------------------------------------------------------
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_46:// LSR $nn
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// ----------------------------------------------------------------------------
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doZ
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opLSR
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fetch_c 5
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// ----------------------------------------------------------------------------
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_48:// PHA
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// ----------------------------------------------------------------------------
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mov r0,m6502_a,lsr#24
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push8 r0
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fetch 3
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// ----------------------------------------------------------------------------
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_49:// EOR #$nn
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// ----------------------------------------------------------------------------
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doIMM
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opEOR
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fetch 2
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// ----------------------------------------------------------------------------
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_4A:// LSR
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// ----------------------------------------------------------------------------
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movs m6502_nz,m6502_a,lsr#25 // Z, N=0
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mov m6502_a,m6502_nz,lsl#24 // result without garbage
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orr cycles,cycles,#CYC_C // Prepare C
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fetch_c 2
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// ----------------------------------------------------------------------------
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_4C:// JMP $nnnn
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// ----------------------------------------------------------------------------
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ldrb r0,[m6502_pc],#1
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ldrb r1,[m6502_pc]
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orr m6502_pc,r0,r1,lsl#8
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encodePC
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fetch 3
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// ----------------------------------------------------------------------------
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_4D:// EOR $nnnn
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// ----------------------------------------------------------------------------
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doABS
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opEOR
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fetch 4
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// ----------------------------------------------------------------------------
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_4E:// LSR $nnnn
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// ----------------------------------------------------------------------------
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doABS
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opLSR
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fetch_c 6
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// ----------------------------------------------------------------------------
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_50:// BVC *
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// ----------------------------------------------------------------------------
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tst cycles,#CYC_V
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ldrsb r0,[m6502_pc],#1
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IT EQ
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addeq m6502_pc,m6502_pc,r0
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IT EQ
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subeq cycles,cycles,#256
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fetch 2
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// ----------------------------------------------------------------------------
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_51:// EOR ($nn),Y
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// ----------------------------------------------------------------------------
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doIIY
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opEOR
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fetch 5
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// ----------------------------------------------------------------------------
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_55:// EOR $nn,X
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// ----------------------------------------------------------------------------
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doZIXf
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opEOR
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fetch 4
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// ----------------------------------------------------------------------------
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_56:// LSR $nn,X
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// ----------------------------------------------------------------------------
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doZIXf
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opLSR
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fetch_c 6
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// ----------------------------------------------------------------------------
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_58:// CLI
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// ----------------------------------------------------------------------------
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bic cycles,cycles,#CYC_I
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fetch 2
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// ----------------------------------------------------------------------------
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_59:// EOR $nnnn,Y
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// ----------------------------------------------------------------------------
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doAIY
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opEOR
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fetch 4
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// ----------------------------------------------------------------------------
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||
_5D:// EOR $nnnn,X
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// ----------------------------------------------------------------------------
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doAIX
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opEOR
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fetch 4
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// ----------------------------------------------------------------------------
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_5E:// LSR $nnnn,X
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// ----------------------------------------------------------------------------
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doAIX
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opLSR
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fetch_c 7
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// ----------------------------------------------------------------------------
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||
_60:// RTS
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// ----------------------------------------------------------------------------
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||
pop16
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add m6502_pc,m6502_pc,#1
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encodePC
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fetch 6
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// ----------------------------------------------------------------------------
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_61:// ADC ($nn,X)
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// ----------------------------------------------------------------------------
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doIIX
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opADC
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fetch_c 6
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// ----------------------------------------------------------------------------
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_65:// ADC $nn
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// ----------------------------------------------------------------------------
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doZ
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opADC
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fetch_c 3
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// ----------------------------------------------------------------------------
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_66:// ROR $nn
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// ----------------------------------------------------------------------------
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doZ
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opROR
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fetch 5
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// ----------------------------------------------------------------------------
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_68:// PLA
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// ----------------------------------------------------------------------------
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pop8 m6502_nz
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mov m6502_a,m6502_nz,lsl#24
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fetch 4
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// ----------------------------------------------------------------------------
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_69:// ADC #$nn
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// ----------------------------------------------------------------------------
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doIMM
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opADC
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||
fetch_c 2
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||
// ----------------------------------------------------------------------------
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||
_6A:// ROR
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||
// ----------------------------------------------------------------------------
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movs cycles,cycles,lsr#1 // get C
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mov m6502_a,m6502_a,rrx
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||
movs m6502_nz,m6502_a,asr#24 // NZ
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and m6502_a,m6502_a,#0xff000000
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adc cycles,cycles,cycles // Set C
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||
fetch 2
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||
// ----------------------------------------------------------------------------
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||
_6C:// JMP ($nnnn) JMP ($data16) 间接寻址 *********************************
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||
// ----------------------------------------------------------------------------
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doABS
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ldr r1, =memmap_tbl
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add r1, globalptr
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and r2,addy,#0xE000 //
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// ldr r1,[r1,r2,lsr#11] // >>11 addr&0x7FF
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lsr r0,r2,#11
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ldr r1,[r1,r0] // 在数据传送之前,将偏移量加到Rn 中,其结果作为传送数据的存储地址
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||
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ldrb m6502_pc,[r1,addy] // //若使用后缀"!",则结果写回到Rn中
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add r1,r1,addy
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||
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ldrb r0,[r1,#1]
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orr m6502_pc,m6502_pc,r0,lsl#8 // m6502_pc=r9使用ORR 指令将近R9的高8 位数据移入到R0低8位
|
||
encodePC
|
||
fetch 5
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||
// ----------------------------------------------------------------------------
|
||
_6D:// ADC $nnnn
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||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opADC
|
||
fetch_c 4
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||
// ----------------------------------------------------------------------------
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||
_6E:// ROR $nnnn
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||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opROR
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_70:// BVS *
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||
// ----------------------------------------------------------------------------
|
||
tst cycles,#CYC_V
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||
ldrsb r0,[m6502_pc],#1
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||
IT NE
|
||
addne m6502_pc,m6502_pc,r0
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||
IT NE
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||
subne cycles,cycles,#256
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||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_71:// ADC ($nn),Y
|
||
// ----------------------------------------------------------------------------
|
||
doIIY
|
||
opADC
|
||
fetch_c 5
|
||
// ----------------------------------------------------------------------------
|
||
_75:// ADC $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIXf
|
||
opADC
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_76:// ROR $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIXf
|
||
opROR
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_78:// SEI
|
||
// ----------------------------------------------------------------------------
|
||
orr cycles,cycles,#CYC_I
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_79:// ADC $nnnn,Y
|
||
// ----------------------------------------------------------------------------
|
||
doAIY
|
||
opADC
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_7D:// ADC $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opADC
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_7E:// ROR $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opROR
|
||
fetch 7
|
||
// ----------------------------------------------------------------------------
|
||
_81:// STA ($nn,X)
|
||
// ----------------------------------------------------------------------------
|
||
doIIX
|
||
opSTORE m6502_a
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_84:// STY $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opSTORE m6502_y
|
||
fetch 3
|
||
// ----------------------------------------------------------------------------
|
||
_85:// STA $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opSTORE m6502_a
|
||
fetch 3
|
||
// ----------------------------------------------------------------------------
|
||
_86:// STX $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opSTORE m6502_x
|
||
fetch 3
|
||
// ----------------------------------------------------------------------------
|
||
_88:// DEY
|
||
// ----------------------------------------------------------------------------
|
||
sub m6502_y,m6502_y,#0x01000000
|
||
mov m6502_nz,m6502_y,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_8A:// TXA
|
||
// ----------------------------------------------------------------------------
|
||
mov m6502_a,m6502_x
|
||
mov m6502_nz,m6502_x,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_8C:// STY $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opSTORE m6502_y
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_8D:// STA $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opSTORE m6502_a
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_8E:// STX $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opSTORE m6502_x
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_90:// BCC *
|
||
// ----------------------------------------------------------------------------
|
||
tst cycles,#CYC_C // Test Carry
|
||
ldrsb r0,[m6502_pc],#1
|
||
IT EQ
|
||
addeq m6502_pc,m6502_pc,r0
|
||
IT EQ
|
||
subeq cycles,cycles,#256
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_91:// STA ($nn),Y
|
||
// ----------------------------------------------------------------------------
|
||
doIIY
|
||
opSTORE m6502_a
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_94:// STY $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIXf
|
||
opSTORE m6502_y
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_95:// STA $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIXf
|
||
opSTORE m6502_a
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_96:// STX $nn,Y
|
||
// ----------------------------------------------------------------------------
|
||
doZIYf
|
||
opSTORE m6502_x
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_98:// TYA
|
||
// ----------------------------------------------------------------------------
|
||
mov m6502_a,m6502_y
|
||
mov m6502_nz,m6502_y,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_99:// STA $nnnn,Y
|
||
// ----------------------------------------------------------------------------
|
||
doAIY
|
||
opSTORE m6502_a
|
||
fetch 5
|
||
// ----------------------------------------------------------------------------
|
||
_9A:// TXS
|
||
// ----------------------------------------------------------------------------
|
||
mov r0,m6502_x,lsr#24
|
||
strb r0,[globalptr,#m6502_s]
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_9D:// STA $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opSTORE m6502_a
|
||
fetch 5
|
||
// ----------------------------------------------------------------------------
|
||
_A0:// LDY #$nn
|
||
// ----------------------------------------------------------------------------
|
||
doIMM
|
||
opLOAD m6502_y
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_A1:// LDA ($nn,X)
|
||
// ----------------------------------------------------------------------------
|
||
doIIX
|
||
opLOAD m6502_a
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_A2:// LDX #$nn
|
||
// ----------------------------------------------------------------------------
|
||
doIMM
|
||
opLOAD m6502_x
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_A4:// LDY $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opLOAD m6502_y
|
||
fetch 3
|
||
// ----------------------------------------------------------------------------
|
||
_A5:// LDA $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opLOAD m6502_a
|
||
fetch 3
|
||
// ----------------------------------------------------------------------------
|
||
_A6:// LDX $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opLOAD m6502_x
|
||
fetch 3
|
||
// ----------------------------------------------------------------------------
|
||
_A8:// TAY
|
||
// ----------------------------------------------------------------------------
|
||
mov m6502_y,m6502_a
|
||
mov m6502_nz,m6502_y,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_A9:// LDA #$nn
|
||
// ----------------------------------------------------------------------------
|
||
doIMM
|
||
opLOAD m6502_a
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_AA:// TAX
|
||
// ----------------------------------------------------------------------------
|
||
mov m6502_x,m6502_a
|
||
mov m6502_nz,m6502_x,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_AC:// LDY $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opLOAD m6502_y
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_AD:// LDA $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opLOAD m6502_a
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_AE:// LDX $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opLOAD m6502_x
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_B0:// BCS *
|
||
// ----------------------------------------------------------------------------
|
||
tst cycles,#CYC_C // Test Carry
|
||
ldrsb r0,[m6502_pc],#1
|
||
IT NE
|
||
addne m6502_pc,m6502_pc,r0
|
||
IT NE
|
||
subne cycles,cycles,#256
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_B1:// LDA ($nn),Y
|
||
// ----------------------------------------------------------------------------
|
||
doIIY
|
||
opLOAD m6502_a
|
||
fetch 5
|
||
// ----------------------------------------------------------------------------
|
||
_B4:// LDY $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIX
|
||
opLOAD m6502_y
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_B5:// LDA $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIX
|
||
opLOAD m6502_a
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_B6:// LDX $nn,Y
|
||
// ----------------------------------------------------------------------------
|
||
doZIY
|
||
opLOAD m6502_x
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_B8:// CLV
|
||
// ----------------------------------------------------------------------------
|
||
bic cycles,cycles,#CYC_V
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_B9:// LDA $nnnn,Y
|
||
// ----------------------------------------------------------------------------
|
||
doAIY
|
||
opLOAD m6502_a
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_BA:// TSX
|
||
// ----------------------------------------------------------------------------
|
||
ldrb m6502_x,[globalptr,#m6502_s]
|
||
mov m6502_x,m6502_x,lsl#24
|
||
mov m6502_nz,m6502_x,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_BC:// LDY $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opLOAD m6502_y
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_BD:// LDA $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opLOAD m6502_a
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_BE:// LDX $nnnn,Y
|
||
// ----------------------------------------------------------------------------
|
||
doAIY
|
||
opLOAD m6502_x
|
||
fetch 4
|
||
// ----------------------------------------------------------------------------
|
||
_C0:// CPY #$nn
|
||
// ----------------------------------------------------------------------------
|
||
doIMM
|
||
opCOMP m6502_y
|
||
fetch_c 2
|
||
// ----------------------------------------------------------------------------
|
||
_C1:// CMP ($nn,X)
|
||
// ----------------------------------------------------------------------------
|
||
doIIX
|
||
opCOMP m6502_a
|
||
fetch_c 6
|
||
// ----------------------------------------------------------------------------
|
||
_C4:// CPY $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opCOMP m6502_y
|
||
fetch_c 3
|
||
// ----------------------------------------------------------------------------
|
||
_C5:// CMP $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opCOMP m6502_a
|
||
fetch_c 3
|
||
// ----------------------------------------------------------------------------
|
||
_C6:// DEC $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opDEC
|
||
fetch 5
|
||
// ----------------------------------------------------------------------------
|
||
_C8:// INY
|
||
// ----------------------------------------------------------------------------
|
||
add m6502_y,m6502_y,#0x01000000
|
||
mov m6502_nz,m6502_y,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_C9:// CMP #$nn
|
||
// ----------------------------------------------------------------------------
|
||
doIMM
|
||
opCOMP m6502_a
|
||
fetch_c 2
|
||
// ----------------------------------------------------------------------------
|
||
_CA:// DEX
|
||
// ----------------------------------------------------------------------------
|
||
sub m6502_x,m6502_x,#0x01000000
|
||
mov m6502_nz,m6502_x,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_CC:// CPY $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opCOMP m6502_y
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_CD:// CMP $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opCOMP m6502_a
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_CE:// DEC $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opDEC
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_D0:// BNE *
|
||
// ----------------------------------------------------------------------------
|
||
tst m6502_nz,#0xff
|
||
ldrsb r0,[m6502_pc],#1
|
||
IT NE
|
||
addne m6502_pc,m6502_pc,r0
|
||
IT NE
|
||
subne cycles,cycles,#256
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_D1:// CMP ($nn),Y
|
||
// ----------------------------------------------------------------------------
|
||
doIIY
|
||
opCOMP m6502_a
|
||
fetch_c 5
|
||
// ----------------------------------------------------------------------------
|
||
_D5:// CMP $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIXf
|
||
opCOMP m6502_a
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_D6:// DEC $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIXf
|
||
opDEC
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_D8:// CLD
|
||
// ----------------------------------------------------------------------------
|
||
bic cycles,cycles,#CYC_D
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_D9:// CMP $nnnn,Y
|
||
// ----------------------------------------------------------------------------
|
||
doAIY
|
||
opCOMP m6502_a
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_DD:// CMP $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opCOMP m6502_a
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_DE:// DEC $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opDEC
|
||
fetch 7
|
||
// ----------------------------------------------------------------------------
|
||
_E0:// CPX #$nn
|
||
// ----------------------------------------------------------------------------
|
||
doIMM
|
||
opCOMP m6502_x
|
||
fetch_c 2
|
||
// ----------------------------------------------------------------------------
|
||
_E1:// SBC ($nn,X)
|
||
// ----------------------------------------------------------------------------
|
||
doIIX
|
||
opSBC
|
||
fetch_c 6
|
||
// ----------------------------------------------------------------------------
|
||
_E4:// CPX $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opCOMP m6502_x
|
||
fetch_c 3
|
||
// ----------------------------------------------------------------------------
|
||
_E5:// SBC $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opSBC
|
||
fetch_c 3
|
||
// ----------------------------------------------------------------------------
|
||
_E6:// INC $nn
|
||
// ----------------------------------------------------------------------------
|
||
doZ
|
||
opINC
|
||
fetch 5
|
||
// ----------------------------------------------------------------------------
|
||
_E8:// INX
|
||
// ----------------------------------------------------------------------------
|
||
add m6502_x,m6502_x,#0x01000000
|
||
mov m6502_nz,m6502_x,asr#24
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_E9:// SBC #$nn
|
||
// ----------------------------------------------------------------------------
|
||
doIMM
|
||
opSBC
|
||
fetch_c 2
|
||
// ----------------------------------------------------------------------------
|
||
_EA:// NOP
|
||
// ----------------------------------------------------------------------------
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_EC:// CPX $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opCOMP m6502_x
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_ED:// SBC $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opSBC
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_EE:// INC $nnnn
|
||
// ----------------------------------------------------------------------------
|
||
doABS
|
||
opINC
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_F0:// BEQ *
|
||
// ----------------------------------------------------------------------------
|
||
tst m6502_nz,#0xff
|
||
ldrsb r0,[m6502_pc],#1
|
||
IT EQ
|
||
addeq m6502_pc,m6502_pc,r0
|
||
IT EQ
|
||
subeq cycles,cycles,#256
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_F1:// SBC ($nn),Y
|
||
// ----------------------------------------------------------------------------
|
||
doIIY
|
||
opSBC
|
||
fetch_c 5
|
||
// ----------------------------------------------------------------------------
|
||
_F5:// SBC $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIXf
|
||
opSBC
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_F6:// INC $nn,X
|
||
// ----------------------------------------------------------------------------
|
||
doZIXf
|
||
opINC
|
||
fetch 6
|
||
// ----------------------------------------------------------------------------
|
||
_F8:// SED
|
||
// ----------------------------------------------------------------------------
|
||
orr cycles,cycles,#CYC_D
|
||
fetch 2
|
||
// ----------------------------------------------------------------------------
|
||
_F9:// SBC $nnnn,Y
|
||
// ----------------------------------------------------------------------------
|
||
doAIY
|
||
opSBC
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_FD:// SBC $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opSBC
|
||
fetch_c 4
|
||
// ----------------------------------------------------------------------------
|
||
_FE:// INC $nnnn,X
|
||
// ----------------------------------------------------------------------------
|
||
doAIX
|
||
opINC
|
||
fetch 7
|
||
// ***********************************************************以下指令是一些HACK游戏需要******************
|
||
_FF:// ISB $????,X 加的，不确定正确 激龟忍者传2无敌HACK需要
|
||
// -------------------------------------------------------------------
|
||
doAIX // MR_AX()//
|
||
opSBC // ISB()//
|
||
// MW_EA()// #define MW_EA() WR6502(EA,DT) // EA .... EFFECTIVE ADDRESS
|
||
fetch 5 // ADD_CYCLE(5)// // DT .... DATA
|
||
// ------------------------------------------------------------------------
|
||
_FB:// ISB $????,X 加的，不确定正确 激龟忍者传2无敌HACK需要
|
||
// -------------------------------------------------------------------
|
||
doAIY // MR_AY()//
|
||
opSBC // ISB()//
|
||
// MW_EA()//
|
||
fetch 5 // ADD_CYCLE(5)//
|
||
// ------------------------------------------------------------------------
|
||
_14:// 加的，不确定正确 激龟忍者传2无敌HACK需要
|
||
// -------------------------------------------------------------------
|
||
add m6502_pc,m6502_pc,#1 // R.PC++//
|
||
fetch 4 // ADD_CYCLE(4)//
|
||
// -------------------------------------------------------------------
|
||
_67:// // RRA $?? 帝国战机无敌HACK需要
|
||
// -------------------------------------------------------------------
|
||
doZ // MR_ZP()//
|
||
opADC // RRA()//
|
||
// MW_ZP()//
|
||
fetch 5 // ADD_CYCLE(5)//
|
||
// --------------------------------------------------------------------
|
||
_03:// // SLO ($??,X) 帝国战机无敌HACK需要
|
||
// -------------------------------------------------------------------
|
||
doIIX // MR_IX()//
|
||
// SLO()//
|
||
// MW_EA()//
|
||
fetch 8// // ADD_CYCLE(8)//
|
||
// -----------------------------------------------------------------
|
||
_07:// // SLO $??
|
||
// ------------------------------------------------------------------
|
||
doZ // MR_ZP()//
|
||
// SLO()//
|
||
// MW_ZP()//
|
||
fetch 5 // ADD_CYCLE(5)//
|
||
|
||
// ----------------------------------------------------------------------------
|
||
_xx:// ??? // invalid opcode 无效的操作码
|
||
// ----------------------------------------------------------------------------
|
||
mov r1,#1 // 不用debug可以直接注译这两行
|
||
bl debug_6502
|
||
|
||
fetch 2
|
||
|
||
|
||
|
||
|
||
|
||
@ .thumb_func
|
||
run6502:
|
||
stmfd sp!,{r4-r11,lr} // 将这几个寄存器中的值保存到堆栈中
|
||
|
||
ldr globalptr,=cpu_data // r10 wram_globals: 读取地址
|
||
ldr cpu_zpage,=NES_RAM // r11
|
||
ldr cpu_zpage,[cpu_zpage] // NES_RAM用了指针
|
||
|
||
ldr r1, =cpuregs
|
||
add r1, globalptr
|
||
ldmia r1,{m6502_nz-m6502_pc} // restore 6502 state恢复6502状态 r3-r9
|
||
add cycles,cycles,r0
|
||
|
||
ldrb r0,[globalptr,#cpuirqf] // cpu中断标志
|
||
cmp r0,#0x01
|
||
beq CheckI // EQ 相等(EQual) irq6502;
|
||
fetch 0 // 提取操作码并运行
|
||
|
||
exit_run:
|
||
ldrb r0,[globalptr,#cpunmif] // cpu中断标志
|
||
cmp r0,#0x01;
|
||
beq NMI6502 // EQ 相等(EQual)
|
||
exit_nmi:
|
||
ldr r0, =cpuregs
|
||
add r0, globalptr
|
||
stmia r0,{m6502_nz-m6502_pc} // 保存6502状态 r3-r9
|
||
ldmfd sp!,{r4-r11,pc} // exit
|
||
@ .end
|
||
|
||
|
||
@ .thumb_func
|
||
NMI6502:
|
||
mov r0,#0
|
||
str r0,[globalptr,#cpunmif] // 清除cpu中断标志
|
||
ldr r12,=NMI_VECTOR // NMI? addy
|
||
bl Vec6502
|
||
sub cycles,cycles,#7*256 // CYCLE=256 6502的中断潜伏期为七 (7) 个周
|
||
// 期; 这也就是说需要需要七 (7) 个周期来移入和移出一个中断
|
||
b exit_nmi // return
|
||
@ .end
|
||
|
||
|
||
default_scanlinehook:
|
||
fetch 0
|
||
|
||
|
||
CheckI:
|
||
// Check Interrupt Disable 检查中断禁用
|
||
tst cycles,#CYC_I
|
||
bne default_scanlinehook // we dont want no stinkin irqs 我们不需要没有讨厌的IRQ
|
||
|
||
irq6502:
|
||
mov r0,#0
|
||
str r0,[globalptr,#cpuirqf] // 清除cpu中断标志
|
||
ldr r12,=IRQ_VECTOR
|
||
bl Vec6502
|
||
fetch 7
|
||
|
||
Vec6502:
|
||
ldr r0,[globalptr,lastbank]
|
||
sub r0,m6502_pc,r0
|
||
push16 // save PC
|
||
encodeP (R) // save P
|
||
|
||
VecCont:
|
||
push8 r0
|
||
orr cycles,cycles,#CYC_I // disable IRQ 禁用IRQ
|
||
ldr r0,[globalptr,#memmap_tbl+28] // 7*4
|
||
// ldrb m6502_pc,[r0,r12]!
|
||
ldrb m6502_pc,[r0,r12] // 在数据传送之前,将偏移量加到Rn 中,其结果作为传送数据的存储地址
|
||
// 若使用后缀"!",则结果写回到Rn中
|
||
add r0,r0,r12 // R12=0xfffc 复位中断向量地址
|
||
ldrb r2,[r0,#1]
|
||
orr m6502_pc,m6502_pc,r2,lsl#8
|
||
encodePC // get IRQ vector得到6502 PC ROM的偏移量
|
||
bx lr
|
||
|
||
@ .thumb_func
|
||
CPU_reset: // called by loadcart (r0-r9 are free to use)
|
||
str lr,[sp,#-4]!
|
||
mov m6502_a,#0
|
||
mov m6502_x,#0
|
||
mov m6502_y,#0
|
||
mov m6502_nz,#0
|
||
ldr m6502_rmem, =readmem_tbl
|
||
add m6502_rmem, globalptr // 把readmem_tbl的地址加载到m6502_rmem
|
||
|
||
// ldr r0,=NES_RAM+0x100 // 256
|
||
ldr r0,=NES_RAM // NES_RAM用了指针
|
||
ldr r0,[r0]
|
||
add r0,#0x100
|
||
|
||
str r0,[globalptr,#m6502_s] // S=0xFD (0x100-3) 把一个寄存器按字存储到存储器中
|
||
mov r0,#0
|
||
str r0,[globalptr,#cpunmif] // 清除cpu中断标志
|
||
str r0,[globalptr,#cpuirqf] // 清除cpu中断标志
|
||
mov cycles,#0 // D=0, C=0, V=0, I=1 disable IRQ.
|
||
|
||
ldr r12,=RES_VECTOR // 复位中断向量地址
|
||
bl Vec6502
|
||
|
||
ldr r0, =cpuregs
|
||
add r0, globalptr // 读取地址
|
||
stmia r0,{m6502_nz-m6502_pc} // 保存6502状态
|
||
|
||
ldr r1,=exit_run
|
||
str r1,[globalptr,#nexttimeout] // 保存指令执行完后下一步的PC地址
|
||
|
||
ldr pc,[sp],#4
|
||
@ .end
|
||
|
||
|
||
|
||
empty_R: // 读地址不正确read bad address (error)
|
||
mov r0,r12
|
||
mov r1,#2
|
||
bl debug_6502
|
||
mov r0,#0
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
@ .thumb_func
|
||
void: // - - - - - - - - -空函数
|
||
mov r0,#0
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
@ .end
|
||
|
||
|
||
ram_R: // ram read ($0000-$1FFF)
|
||
bic addy,addy,#0x1f800 // only 0x07FF is RAM
|
||
ldrb r0,[cpu_zpage,addy]
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
ram_W: // ram write ($0000-$1FFF)
|
||
bic addy,addy,#0x1f800 // only 0x07FF is RAM
|
||
strb r0,[cpu_zpage,addy] // cpu_zpage RN r11 ;=CPU_RAM
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
sram_R: // sram read ($6000-$7FFF)
|
||
sub r1,addy,#0x6000
|
||
ldr r2,[globalptr,#memmap_tbl+12]
|
||
ldrb r0,[r2,r1]
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
sram_W: // sram write ($6000-$7FFF)
|
||
sub addy,addy,#0x6000
|
||
ldr r1,[globalptr,#memmap_tbl+12]
|
||
strb r0,[r1,addy]
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
rom_R60: // rom read ($6000-$7FFF)
|
||
ldr r1,[globalptr,#memmap_tbl+12]
|
||
ldrb r0,[r1,addy]
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
rom_R80: // rom read ($8000-$9FFF)
|
||
ldr r1,[globalptr,#memmap_tbl+16]
|
||
ldrb r0,[r1,addy]
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
rom_RA0: // rom read ($A000-$BFFF)
|
||
ldr r1,[globalptr,#memmap_tbl+20]
|
||
ldrb r0,[r1,addy]
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
rom_RC0: // rom read ($C000-$DFFF)
|
||
ldr r1,[globalptr,#memmap_tbl+24]
|
||
ldrb r0,[r1,addy]
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
rom_RE0: // ;rom read ($E000-$FFFF)
|
||
ldr r1,[globalptr,#memmap_tbl+28]
|
||
ldrb r0,[r1,addy]
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
IO_R: // I/O read
|
||
mov r2,#0x4018 // $4018-$6000
|
||
cmp r12,r2
|
||
bhi Read_Low // HI 无符号数大于 C==1 && Z==0
|
||
|
||
sub r1,r12,#0x4000 // addy=r12
|
||
subs r1,r1,#0x15
|
||
bmi empty_R // 读地址不正确 MI 负数(MInus) N==1
|
||
cmp r1,#3
|
||
ldr r2,=io_read_tbl // 改过，加3行
|
||
add r2,r2,r1,lsl#2 // <<2
|
||
IT MI
|
||
ldrmi pc,[r2]
|
||
|
||
b empty_R // 读地址不正确
|
||
|
||
|
||
io_read_tbl:
|
||
.word apu_4015R // void_4015r ;4015 (sound)
|
||
.word joy0_R // 4016: controller 1
|
||
.word joy1_R // 4017: controller 2
|
||
|
||
IO_W: // I/O write
|
||
mov r2,#0x4018 // $4018-$6000
|
||
cmp r12,r2
|
||
bhi Write_Low // HI 无符号数大于 C==1 && Z==0
|
||
sub r1,r12,#0x4000 // addy=r12
|
||
cmp r1,#0x18
|
||
ldr r2,=io_write_tbl // 改过，加3行
|
||
add r2,r2,r1,lsl#2 // <<2
|
||
IT MI
|
||
ldrmi pc,[r2] // 直接操作pc太他妈危险了
|
||
b empty_R // 读地址不正确
|
||
|
||
|
||
io_write_tbl:
|
||
.word apu_w // void_4000w
|
||
.word apu_w // _4001w
|
||
.word apu_w // _4002w
|
||
.word apu_w // _4003w
|
||
.word apu_w // _4004w
|
||
.word apu_w // _4005w
|
||
.word apu_w // _4006w
|
||
.word apu_w // _4007w
|
||
.word apu_w // _4008w
|
||
.word apu_w // void
|
||
.word apu_w // _400aw
|
||
.word apu_w // void_400bw
|
||
.word apu_w // void_400cw
|
||
.word apu_w // void
|
||
.word apu_w // void_400ew
|
||
.word apu_w // void_400fw
|
||
.word apu_w // void_4010w
|
||
.word apu_w // void_4011w
|
||
.word apu_w // void_4012w
|
||
.word apu_w // void_4013w
|
||
.word dma_W // $4014: Sprite DMA transfer
|
||
.word apu_4015w // void_4015w 声音通道切换
|
||
.word joy0_W // $4016: Joypad 0 write joypad_write_ptr
|
||
.word void // joy1_W $4017:
|
||
|
||
|
||
.extern asm_Mapper_ReadLow
|
||
|
||
@ .thumb_func
|
||
Read_Low: // $5000-$6000 mapper->MemoryReadLow(addr);
|
||
stmfd sp!,{r3,lr} // LR 寄存器放栈
|
||
mov r0,r12
|
||
bl asm_Mapper_ReadLow
|
||
ldmfd sp!,{r3,lr}
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
@ .end
|
||
|
||
|
||
.extern asm_Mapper_WriteLow
|
||
|
||
@ .thumb_func
|
||
Write_Low: // $5000-$6000 mapper->MemoryWriteLow( data, addr);
|
||
stmfd sp!,{r3,lr} // LR 寄存器放栈
|
||
mov r1,r12
|
||
bl asm_Mapper_WriteLow
|
||
ldmfd sp!,{r3,lr}
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
@ .end
|
||
|
||
|
||
.extern Apu_Write
|
||
.extern Apu_Write4015
|
||
|
||
apu_w: // 0x4000--0x4013
|
||
stmfd sp!,{r3,lr} // LR 寄存器放栈
|
||
bl Apu_Write
|
||
ldmfd sp!,{r3,lr}
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
apu_4015w:
|
||
stmfd sp!,{r3,lr}
|
||
bl Apu_Write4015
|
||
ldmfd sp!,{r3,lr}
|
||
orr lr,#0x01
|
||
bx lr
|
||
|
||
|
||
.extern Apu_Read4015
|
||
|
||
apu_4015R:
|
||
stmfd sp!,{r3,lr}
|
||
add r0,r1,#0x15
|
||
bl Apu_Read4015
|
||
ldmfd sp!,{r3,lr}
|
||
orr lr,#0x01
|
||
bx lr
|
||
|
||
|
||
dma_W: // (4014) sprite DMA transfer 精灵DMA传输 DMA访问精灵RAM：
|
||
// 通过写一个值xx到这个端口，引起CPU内存地址为$xx00－$xxFF的区域传送到精灵内存
|
||
sub cycles,cycles,#512*256
|
||
stmfd sp!,{r3,lr}
|
||
and r1,r0,#0xe0
|
||
ldr r2, =memmap_tbl
|
||
add r2, globalptr
|
||
lsr r1,r1,#3
|
||
ldr r2,[r2,r1]
|
||
and r0,r0,#0xff
|
||
add r2,r2,r0,lsl#8 // addy r2=DMA source 源
|
||
ldr r1,=spr_ram // r1 DMA的 目的地 ppu.c
|
||
ldr r1,[r1] // spr_ram用了指针
|
||
mov r0,#64 // 256/4/8
|
||
copy_:
|
||
subs r0,r0,#1 // -1
|
||
ldr r3,[r2,r0,lsl#2]
|
||
str r3,[r1,r0,lsl#2] // <<2 *4
|
||
bne copy_
|
||
ldmfd sp!,{r3,lr}
|
||
orr lr,#0x01
|
||
bx lr
|
||
|
||
|
||
.extern PADdata
|
||
.extern PADdata1
|
||
|
||
joy0_W: // 4016 手柄1键值 [7:0]右7 左6 下5 上4 Start3 Select2 B1 A0 )
|
||
tst r0,#1 // 0＝写，1＝读
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
IT NE
|
||
bxne lr // NE 不等（NotEqual）
|
||
ldr r1,=PADdata; // 手柄1键值
|
||
ldr r1,[r1]
|
||
str r1,[globalptr,#joy0data]
|
||
ldr r1,=PADdata1; // 手柄1键值
|
||
ldr r1,[r1]
|
||
str r1,[globalptr,#joy1data]
|
||
bx lr
|
||
|
||
|
||
// 在手柄0里面把手柄1的数据一起读取了，所以这个函数不需要了
|
||
joy1_W: // 4017 手柄1键值 [7:0]右7 左6 下5 上4 Start3 Select2 B1 A0 )
|
||
// tst r0,#1 ; 0＝??，1＝读
|
||
// orr lr,#0x01 ;lr最低位置1防止进入arm状态
|
||
// bxne lr ;NE 不等（NotEqual）
|
||
bx lr
|
||
|
||
joy0_R:
|
||
// 4016
|
||
ldr r0,[globalptr,#joy0data] // 串行数据 当前读取位;joy0data是键值
|
||
mov r1,r0,lsr#1 // >>1
|
||
str r1,[globalptr,#joy0data]
|
||
and r0,r0,#1 // &1
|
||
orr r0,r0,#0x40 // |0x40
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
joy1_R:
|
||
// 4017
|
||
ldr r0,[globalptr,#joy1data] // 串行数据 当前读取位;joy0data是键值
|
||
mov r1,r0,lsr#1 // >>1
|
||
str r1,[globalptr,#joy1data]
|
||
and r0,r0,#1 // &1
|
||
orr r0,r0,#0x40 // |0x80？ 0xf8?
|
||
orr lr,#0x01 // lr最低位置1防止进入arm状态
|
||
bx lr
|
||
|
||
.global K6502_Read
|
||
@ .thumb_func
|
||
K6502_Read:
|
||
// apu Rendering DPCM channel #5 r0=APU->ApuC5Address不确定正确*
|
||
stmfd sp!,{lr}
|
||
mov r1,r0,lsr#13 // >>13= & 0xe000
|
||
ldr r2,=CPU_RAM // 存储器映象 ram+rom
|
||
ldr r1,[r2,r1,lsl#2] // lookup rom ptr..查找ptr
|
||
bic r0,r0,#0xe000 // and r0,#0x1fff &0x1fff
|
||
ldrb r0,[r1,r0]
|
||
ldmfd sp!,{lr}
|
||
bx lr
|
||
@ .end
|
||
|
||
.extern PPU_WriteToPort
|
||
.extern PPU_ReadFromPort
|
||
|
||
|
||
PPU_W:
|
||
stmfd sp!,{r3,lr}
|
||
mov r1,r12
|
||
bl PPU_WriteToPort
|
||
ldmfd sp!,{r3,lr}
|
||
orr lr,#0x01
|
||
bx lr
|
||
|
||
PPU_R:
|
||
stmfd sp!,{r3,lr}
|
||
mov r0,r12
|
||
bl PPU_ReadFromPort
|
||
ldmfd sp!,{r3,lr}
|
||
orr lr,#0x01
|
||
bx lr
|
||
|
||
|
||
op_table:
|
||
.word _00,_01,_xx,_03,_xx,_05,_06,_07,_08,_09,_0A,_xx,_xx,_0D,_0E,_xx
|
||
.word _10,_11,_xx,_xx,_14,_15,_16,_xx,_18,_19,_xx,_xx,_xx,_1D,_1E,_xx
|
||
.word _20,_21,_xx,_xx,_24,_25,_26,_xx,_28,_29,_2A,_xx,_2C,_2D,_2E,_xx
|
||
.word _30,_31,_xx,_xx,_xx,_35,_36,_xx,_38,_39,_xx,_xx,_xx,_3D,_3E,_xx
|
||
.word _40,_41,_xx,_xx,_xx,_45,_46,_xx,_48,_49,_4A,_xx,_4C,_4D,_4E,_xx
|
||
.word _50,_51,_xx,_xx,_xx,_55,_56,_xx,_58,_59,_xx,_xx,_xx,_5D,_5E,_xx
|
||
.word _60,_61,_xx,_xx,_xx,_65,_66,_67,_68,_69,_6A,_xx,_6C,_6D,_6E,_xx
|
||
.word _70,_71,_xx,_xx,_xx,_75,_76,_xx,_78,_79,_xx,_xx,_xx,_7D,_7E,_xx
|
||
.word _xx,_81,_xx,_xx,_84,_85,_86,_xx,_88,_xx,_8A,_xx,_8C,_8D,_8E,_xx
|
||
.word _90,_91,_xx,_xx,_94,_95,_96,_xx,_98,_99,_9A,_xx,_xx,_9D,_xx,_xx
|
||
.word _A0,_A1,_A2,_xx,_A4,_A5,_A6,_xx,_A8,_A9,_AA,_xx,_AC,_AD,_AE,_xx
|
||
.word _B0,_B1,_xx,_xx,_B4,_B5,_B6,_xx,_B8,_B9,_BA,_xx,_BC,_BD,_BE,_xx
|
||
.word _C0,_C1,_xx,_xx,_C4,_C5,_C6,_xx,_C8,_C9,_CA,_xx,_CC,_CD,_CE,_xx
|
||
.word _D0,_D1,_xx,_xx,_xx,_D5,_D6,_xx,_D8,_D9,_xx,_xx,_xx,_DD,_DE,_xx
|
||
.word _E0,_E1,_xx,_xx,_E4,_E5,_E6,_xx,_E8,_E9,_EA,_xx,_EC,_ED,_EE,_xx
|
||
.word _F0,_F1,_xx,_xx,_xx,_F5,_F6,_xx,_F8,_F9,_xx,_FB,_xx,_FD,_FE,_FF
|
||
|
||
|
||
.section .data
|
||
.type cpu_data, %object
|
||
cpu_data:
|
||
.word 0 // opz # 4 代码表地址
|
||
// readmem_tbl
|
||
.word ram_R // $0000
|
||
.word PPU_R // $2000
|
||
.word IO_R // $4000
|
||
.word sram_R // $6000
|
||
.word rom_R80 // $8000
|
||
.word rom_RA0 // $A000
|
||
.word rom_RC0 // $C000
|
||
.word rom_RE0 // $E000
|
||
// writemem_tbl
|
||
.word ram_W // $0000
|
||
.word PPU_W // $2000 r0传参数
|
||
.word IO_W // $4000
|
||
.word sram_W // $6000
|
||
.word void // $8000
|
||
.word void // $A000
|
||
.word void // $C000
|
||
.word void // $E000
|
||
CPU_RAM: // memmap_tbl 存储器映象
|
||
.word NES_RAM // $0000 0000-7fff keep $400 byte aligned for 6502 stack shit
|
||
.word NES_RAM // $2000 should 保持1024字节对齐
|
||
.word NES_RAM // $4000 never
|
||
.word NES_SRAM // NES_RAM-0x5800 ;$6000 change改变
|
||
rommap:
|
||
.space 4*4 // $8000-FFFF memmap_tbl+16
|
||
cpustate:
|
||
// group these together for save/loadstate
|
||
.space 7*4 // cpuregs (nz,c,a,x,y,cycles,pc)
|
||
.word 0 // m6502_s:
|
||
.word 0 // lastbank: 最后MEMMAP添加到PC （用于计算当前的PC ）
|
||
.word 0 // nexttimeout: jump here when cycles runs out 跳到下一个时钟周期运行
|
||
.word 0 // rombase # 4 ;//ROM开始地址
|
||
.word 0 // romnumber # 4 ;//
|
||
.word 0 // rommask # 4 ;//ROM掩膜 rommask=romsize-1
|
||
.word 0 // joy0data # 4 ;//手柄1串行数据
|
||
.word 0 // joy1data # 4 ;//手柄2串行数据
|
||
clocks:
|
||
.word 0 // clocksh # 4 ;//执行的时钟数 apu用
|
||
cpunmi:
|
||
.word 0 // cpunmif # 4 ;cpu中断标志
|
||
cpuirq:
|
||
.word 0 // cpuirqf # 4 ;cpu中断标志
|
||
|
||
|
||
|