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65816.js
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added AND and many addressing modes for it

This commit is contained in:
Preston Skupinski 2011-05-08 00:41:57 -04:00
parent c716e6e2f0
commit 4bac875b5c
1 changed files with 134 additions and 7 deletions
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141
cpu.js
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@ -94,7 +94,12 @@ function CPU_65816() {
0xcd : CMP_absolute, 0xe0 : CPX_const,
0xec : CPX_absolute, 0xe4 : CPX_direct_page,
0xc0 : CPY_const, 0xcc : CPY_absolute,
0xc4 : CPY_direct_page };
0xc4 : CPY_direct_page, 0x29 : AND_const,
0x2d : AND_absolute, 0x25 : AND_direct_page,
0x32 : AND_direct_page_indirect,
0x3d : AND_absolute_indexed_x,
0x39 : AND_absolute_indexed_y,
0x35 : AND_direct_page_indexed_x };
/**
* Take a raw hex string representing the program and execute it.
@ -173,6 +178,116 @@ var MMU = {
}
};
var AND_const = {
bytes_required:function(cpu) {
if(cpu.p.m) {
return 2;
} else {
return 3;
}
},
execute:function(cpu, bytes) {
if(cpu.p.m) {
cpu.r.a &= bytes[0];
cpu.p.n = cpu.r.a >> 7;
} else {
cpu.r.a &= (bytes[1]<<8)|bytes[0];
cpu.p.n = cpu.r.a >> 15;
}
if(cpu.r.a===0) {
cpu.p.z = 1;
} else {
cpu.p.z = 0;
}
}
};
var AND_absolute = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var location = (bytes[1]<<8)|bytes[0];
if(cpu.p.m) {
AND_const.execute(cpu, [cpu.mmu.read_byte(location)]);
} else {
var low_byte = cpu.mmu.read_byte(location);
var high_byte = cpu.mmu.read_byte(location+1);
AND_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var AND_direct_page = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
var location = bytes[0] + cpu.r.d;
if(cpu.p.m) {
AND_const.execute(cpu, cpu.mmu.read_byte(location));
} else {
var low_byte = cpu.mmu.read_byte(location);
var high_byte = cpu.mmu.read_byte(location+1);
AND_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var AND_direct_page_indirect = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
var location = bytes[0] + cpu.r.d;
var low_byte_loc = cpu.mmu.read_byte(location);
var high_byte_loc = cpu.mmu.read_byte(location+1);
var absolute_location = (high_byte_loc<<8) | low_byte_loc;
if(cpu.p.m) {
AND_const.execute(cpu, [cpu.mmu.read_byte(absolute_location)]);
} else {
var low_byte = cpu.mmu.read_byte(absolute_location);
var high_byte = cpu.mmu.read_byte(absolute_location+1);
AND_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var AND_absolute_indexed_x = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var location = ((bytes[1]<<8)|bytes[0])+cpu.r.x;
var location_high_byte = (location & 0xff00)>>8;
var location_low_byte = location & 0x00ff;
AND_absolute.execute(cpu, [location_low_byte, location_high_byte]);
}
};
var AND_absolute_indexed_y = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var location = ((bytes[1]<<8)|bytes[0])+cpu.r.y;
var location_high_byte = (location & 0xff00)>>8;
var location_low_byte = location & 0x00ff;
AND_absolute.execute(cpu, [location_low_byte, location_high_byte]);
}
};
var AND_direct_page_indexed_x = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
AND_direct_page.execute(cpu, [bytes[0]+cpu.r.x]);
}
};
var CPX_const = {
bytes_required:function(cpu) {
if(cpu.p.x) {
@ -496,7 +611,10 @@ var SBC_absolute_indexed_x = {
return 3;
},
execute:function(cpu, bytes) {
SBC_absolute.execute(cpu, ((bytes[1]<<8)|bytes[0])+cpu.r.x);
var location = ((bytes[1]<<8)|bytes[0])+cpu.r.x;
var location_high_byte = (location & 0xff00)>>8;
var location_low_byte = location & 0x00ff;
SBC_absolute.execute(cpu, [location_low_byte, location_high_byte]);
}
};
@ -505,7 +623,10 @@ var SBC_absolute_indexed_y = {
return 3;
},
execute:function(cpu, bytes) {
SBC_absolute.execute(cpu, ((bytes[1]<<8)|bytes[0])+cpu.r.y);
var location = ((bytes[1]<<8)|bytes[0])+cpu.r.y;
var location_high_byte = (location & 0xff00)>>8;
var location_low_byte = location & 0x00ff;
SBC_absolute.execute(cpu, [location_low_byte, location_high_byte]);
}
};
@ -514,7 +635,7 @@ var SBC_direct_page_indexed_x = {
return 2;
},
execute:function(cpu, bytes) {
SBC_direct_page.execute(cpu, bytes[0]+cpu.r.x);
SBC_direct_page.execute(cpu, [bytes[0]+cpu.r.x]);
}
};
@ -651,7 +772,10 @@ var ADC_absolute_indexed_x = {
return 3;
},
execute:function(cpu, bytes) {
ADC_absolute.execute(cpu, ((bytes[1]<<8)|bytes[0])+cpu.r.x);
var location = ((bytes[1]<<8)|bytes[0])+cpu.r.x;
var location_high_byte = (location & 0xff00)>>8;
var location_low_byte = location & 0x00ff;
ADC_absolute.execute(cpu, [location_low_byte, location_high_byte]);
}
};
@ -660,7 +784,10 @@ var ADC_absolute_indexed_y = {
return 3;
},
execute:function(cpu, bytes) {
ADC_absolute.execute(cpu, ((bytes[1]<<8)|bytes[0])+cpu.r.y);
var location = ((bytes[1]<<8)|bytes[0])+cpu.r.y;
var location_high_byte = (location & 0xff00)>>8;
var location_low_byte = location & 0x00ff;
ADC_absolute.execute(cpu, [location_low_byte, location_high_byte]);
}
};
@ -669,7 +796,7 @@ var ADC_direct_page_indexed_x = {
return 2;
},
execute:function(cpu, bytes) {
ADC_direct_page.execute(cpu, bytes[0]+cpu.r.x);
ADC_direct_page.execute(cpu, [bytes[0]+cpu.r.x]);
}
};