The 6502 Microprocessor Resource
http://forum.6502.org/
Code: Select all
65C02 Monitor v5.1.1 (12-02-12) Ready
By Lee Davison and Joshua Walker
(Press ? for help)
Current commands are :
Syntax = {} required, [] optional, HHHH hex address, DD hex data
[HHHH][ HHHH]{Return} - Hex dMPJSRLDALDXLDYLSRNOPORAPHAPHPPHXPHYPLAPLPPLXPLYROLRORRTIRTSSBCSECSEDSEISTASTXSTYSTZTAXTAYTRBTSBTSXTXATXSTYAWAISTPBBRBBSRMBSMB.DB.DW.DS???
Current commands are :
Syntax = {} required, [] optional, HHHH hex address, DD hex data
[HHHH][ HHHH]{Return} - Hex dMPJSRLDALDXLDYLSRNOPORAPHAPHPPHXPHYPLAPLPPLXPLYROLRORRTIRTSSBCSECSEDSEISTASTXSTYSTZTAXTAYTRBTSBTSXTXATXSTYAWAISTPBBRBBSRMBSMB.DB.DW.DS???
Current commands are :
Syntax = {} required, [] optional, HHHH hex address, DD hex data
[HHHH][ HHHH]{Return} - Hex dMPJSRLDALDXLDYLSRNOPORAPHAPHPPHXPHYPLAPLPPLXPLYROLRORRTIRTSSBCSECSEDSEISTASTXSTYSTZTAXTAYTRBTSBTSXTXATXSTYAWAISTPBBRBBSRMBSMB.DB.DW.DS???
Current commands are :
Syntax = {} required, [] optional, HHHH hex address, DD hex data
[HHHH][ HHHH]{Return} - Hex dMPJSRLDALDXLDYLSRNOPORAPHAPHPPHXPHYPLAPLPPLXPLYROLRORRTIRTSSBCSECSEDSEISTASTXSTYSTZTAXTAYTRBTSBTSXTXATXSTYAWAISTPBBRBBSRMBSMB.DB.DW.DS???
Current commands are :
Syntax = {} required, [] optional, HHHH hex address, DD hex data
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Help_Cmd: lda #<HelpTxt ; lower byte - Menu of Commands
sta AddrPtr ;
lda #>HelpTxt ; upper byte
sta AddrPtr+1 ;
bra Help_Cmd3 ;
Help_Cmd4: cmp #$7e ; "~"
beq Help_Cmd1 ;
jsr Output ;
bra Help_Cmd2 ;
Help_Cmd1: jsr Print_CR ;
Help_Cmd2: jsr Inc_AddrPtr ; <--- This is where it's breaking
Help_Cmd3: lda (AddrPtr) ;
bne Help_Cmd4 ;
rts ;
Inc_AddrPtr: INC AddrPtr ; increments AddrPtr
BNE Inc_addr1 ;
INC AddrPtr+1 ;
Inc_addr1: RTS
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.byte "JMP" ;1C
.byte "JSR" ;1D
.byte "LDA" ;1E
.byte "LDX" ;1F
.byte "LDY" ;20
.byte "LSR" ;21
.byte "NOP" ;22
.byte "ORA" ;23
.byte "PHA" ;24
.byte "PHP" ;25
.byte "PHX" ;26
.byte "PHY" ;27
.byte "PLA" ;28
.byte "PLP" ;29
.byte "PLX" ;2A
.byte "PLY" ;2B
.byte "ROL" ;2C
.byte "ROR" ;2D
.byte "RTI" ;2E
.byte "RTS" ;2F
.byte "SBC" ;30
.byte "SEC" ;31
.byte "SED" ;32
.byte "SEI" ;33
.byte "STA" ;34
.byte "STX" ;35
.byte "STY" ;36
.byte "STZ" ;37
.byte "TAX" ;38
.byte "TAY" ;39
.byte "TRB" ;3A
.byte "TSB" ;3B
.byte "TSX" ;3C
.byte "TXA" ;3D
.byte "TXS" ;3E
.byte "TYA" ;3F
.byte "WAI" ;40
.byte "STP" ;41
.byte "BBR" ;42 4Byte Opcodes
.byte "BBS" ;43
.byte "RMB" ;44
.byte "SMB" ;45
.byte ".DB" ;46 define 1 byte for assembler
.byte ".DW" ;47 define 1 word for assembler
.byte ".DS" ;48 define a string block for assembler
.byte "???" ;49 for invalid opcode
;
;
HelpTxt: .byte "~Current commands are :~"
.byte "Syntax = {} required, [] optional, HHHH hex address, DD hex data~"
.byte "~"
.byte "[HHHH][ HHHH]{Return} - Hex dump address(s)(up to 16 if no address entered)~"
.byte "[HHHH]{.HHHH}{Return} - Hex dump range of addresses (16 per line)~"
.byte "[HHHH]{:DD}[ DD]{Return} - Change data bytes~"
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#define UMASK 0xFF
#define C_FLAG 0b00000001
#define Z_FLAG 0b00000010
#define I_FLAG 0b00000100
#define D_FLAG 0b00001000
#define B_FLAG 0b00010000
#define X_FLAG 0b00100000
#define V_FLAG 0b01000000
#define N_FLAG 0b10000000
void INC(int addr)
{
int value;
value = memReadByte( addr );
++value;
memStoreByte( addr, value&UMASK ); //mask off the lower byte
setNVflags(value);
}
//set zero and negative processor flags based on result
void setNVflags(int val)
{
if( val )
{regP &= ~Z_FLAG;}
else
{regP |= Z_FLAG;}
if( val & N_FLAG )
{regP |= N_FLAG;}
else
{regP &= ~N_FLAG;}
}
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case 0xd0: // BNE
offset = popByte();
if (!zeroSet()) {jumpBranch(offset); }
break;
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int zeroSet() { return regP & Z_FLAG;}
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void setNVflags(int value)
{
if( value ) regP &= 0xfd; else regP |= 0x02;
if( value & 0x80 ) regP |= 0x80; else regP &= 0x7f;
}
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void INC(int addr)
{
int value;
value = memReadByte( addr );
dmplcd(value); /* substitute your lcd dump code here */
++value;
memStoreByte( addr, value&UMASK ); //mask off the lower byte
setNVflags(value);
value = memReadByte( addr );
dmplcd(value); /* substitute your lcd dump code here */
}
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private int setFlagsNZ(int i) {
status &= ~(ZERO_MASK + NEGATIVE_MASK);
if (i == 0) {
status |= ZERO_MASK;
}
if ((i & NEGATIVE_MASK) != 0) {
status |= NEGATIVE_MASK;
}
return i;
}
public void doInc(int addr, int value) {
int result = fetchByte(addr);
result = result + value;
if (result == -1) {
result = 255;
}
if (result == 256) {
result = 0;
}
setFlagsNZ(result);
putByte(addr, result);
}
public void INC(int addr) {
doInc(addr, 1);
}
public void DEC(int addr) {
doInc(addr, -1);
}
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65C02 Monitor v5.1.1 (12-02-12) Ready
By Lee Davison and Joshua Walker
(Press ? for help)
>R
PC=CD30 A=11 X=00 Y=BF S=6C P=FF (NVRBDIZC)=11111111 <----huh?
>E800L
E800- L 4C INX <----- Nope!
E801- LiL 4C E9 4C JMP $4CE9
E804- . 88 INX
E805- h E8 INX
E806- L9h 4C B9 E8 JMP $E8B9
E809- L6 4C B6 LDX $B6,Y
E80B- hL1 E8 4C B1 JMP $B14C
E80E- hL" E8 4C A2 JMP $A24C
E811- hL. E8 4C 99 JMP $994C
E814- hL. E8 4C 95 JMP $954C
E817- hL< E8 4C 3C JMP $3C4C
E81A- iLB E9 4C 42 JMP $424C
E81D- iL4 E9 4C 34 JMP $344C
E820- iL. E9 4C 2E JMP $2E4C
E823- iL8 E9 4C 38 JMP $384C
E826- iLA E9 4C C1 JMP $C14C
E829- hLE E8 4C C5 JMP $C54C
E82C- h P E8 20 50 JSR $5020
E82F- C= 43 3D 20 AND $203D,X
E832- A 20 41 EOR ($41,X)
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