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65816.js
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added ROL and all of its addressing modes

This commit is contained in:
Preston Skupinski 2011-05-08 17:03:23 -04:00
parent b1c6249169
commit b3488669a8
1 changed files with 134 additions and 1 deletions
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135
cpu.js
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@ -116,7 +116,10 @@ function CPU_65816() {
0x56 : LSR_direct_page_indexed_x, 0x0a : ASL_accumulator,
0x0e : ASL_absolute, 0x06 : ASL_direct_page,
0x1e : ASL_absolute_indexed_x,
0x16 : ASL_direct_page_indexed_x };
0x16 : ASL_direct_page_indexed_x, 0x2a : ROL_accumulator,
0x2e : ROL_absolute, 0x26 : ROL_direct_page,
0x3e : ROL_absolute_indexed_x,
0x36 : ROL_direct_page_indexed_x };
/**
* Take a raw hex string representing the program and execute it.
@ -195,6 +198,136 @@ var MMU = {
}
};
var ROL_accumulator = {
bytes_required:function() {
return 1;
},
execute:function(cpu) {
if(cpu.p.m) {
var old_c = cpu.p.c;
cpu.p.c = cpu.r.a >> 7;
cpu.r.a = cpu.r.a << 1;
cpu.r.a &= 0xfe;
cpu.r.a |= old_c;
cpu.p.n = cpu.r.a >> 7;
} else {
var old_c = cpu.p.c;
cpu.p.c = cpu.r.a >> 15;
cpu.r.a = cpu.r.a << 1;
cpu.r.a &= 0xfffe;
cpu.r.a |= old_c;
cpu.p.n = cpu.r.a >> 15;
}
if(cpu.r.a===0) {
cpu.p.z = 1;
} else {
cpu.p.z = 0;
}
}
};
var ROL_absolute = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var location = (bytes[1]<<8)|bytes[0];
var shiftee;
if(cpu.p.m) {
shiftee = cpu.mmu.read_byte(location);
var old_c = cpu.p.c;
cpu.p.c = shiftee >> 7;
shiftee = shiftee << 1;
shiftee &= 0xfe;
shiftee |= old_c;
cpu.p.n = shiftee >> 7;
cpu.mmu.store_byte(location, shiftee);
} else {
var low_byte = cpu.mmu.read_byte(location);
var high_byte = cpu.mmu.read_byte(location+1);
shiftee = (high_byte<<8)|low_byte;
var old_c = cpu.p.c;
cpu.p.c = shiftee >> 15;
shiftee = shiftee << 1;
shiftee &= 0xfffe;
shiftee |= old_c;
cpu.p.n = shiftee >> 15;
low_byte = shiftee & 0x00ff;
high_byte = shiftee >> 8;
cpu.mmu.store_byte(location, low_byte);
cpu.mmu.store_byte(location+1, high_byte);
}
if(shiftee===0) {
cpu.p.z = 1;
} else {
cpu.p.z = 0;
}
}
};
var ROL_direct_page = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
var location = bytes[0]+cpu.r.d;
var shiftee;
if(cpu.p.m) {
shiftee = cpu.mmu.read_byte(location);
var old_c = cpu.p.c;
cpu.p.c = shiftee >> 7;
shiftee = shiftee << 1;
shiftee &= 0xfe;
shiftee |= old_c;
cpu.p.n = shiftee >> 7;
cpu.mmu.store_byte(location, shiftee);
} else {
var low_byte = cpu.mmu.read_byte(location);
var high_byte = cpu.mmu.read_byte(location+1);
shiftee = (high_byte<<8)|low_byte;
var old_c = cpu.p.c;
cpu.p.c = shiftee >> 15;
shiftee = shiftee << 1;
shiftee &= 0xfffe;
shiftee |= old_c;
cpu.p.n = shiftee >> 15;
low_byte = shiftee & 0x00ff;
high_byte = shiftee >> 8;
cpu.mmu.store_byte(location, low_byte);
cpu.mmu.store_byte(location+1, high_byte);
}
if(shiftee===0) {
cpu.p.z = 1;
} else {
cpu.p.z = 0;
}
}
};
var ROL_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 >> 8;
var location_low_byte = location & 0x00ff;
ROL_absolute.execute(cpu, [location_low_byte, location_high_byte]);
}
};
var ROL_direct_page_indexed_x = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
ROL_direct_page.execute(cpu, [bytes[0]+cpu.r.x]);
}
};
var ASL_accumulator = {
bytes_required:function() {
return 1;