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65816.js
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move common addressing functionality for stack relative to cpu_lib and use that as the basis for instructions that utilize that addressing mode

This commit is contained in:
Preston Skupinski 2011-12-31 15:52:45 -05:00
parent 539aaff3ce
commit 72508335ba
1 changed files with 27 additions and 156 deletions
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183
cpu.js
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@ -76,6 +76,25 @@ var cpu_lib = {
direct_page_instruction.execute(cpu, [bytes[0]+cpu.r.x]);
};
},
Stack_relative: function(instruction) {
this.bytes_required = function() {
return 2;
};
this.execute = function(cpu, bytes) {
cpu.cycle_count+=2;
var memory_location = cpu.r.s + bytes[0];
if(cpu.p.e) {
memory_location = 0x100 | (memory_location & 0xff);
} else if(cpu.p.m) {
instruction.execute(cpu, [cpu.mmu.read_byte(memory_location)]);
} else {
instruction.execute(cpu, [cpu.mmu.read_byte(memory_location),
cpu.mmu.read_byte(memory_location+1)]);
}
};
}
}
};
@ -1447,28 +1466,7 @@ var EOR_absolute_indexed_y = {
var EOR_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(EOR_direct_page);
var EOR_stack_relative = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=2;
if(cpu.p.e) {
var memory_location = 0x100 | ((cpu.r.s + bytes[0]) & 0xff);
EOR_const.execute(cpu, [cpu.mmu.read_byte(memory_location)]);
} else {
if(cpu.p.m) {
EOR_const.execute(cpu, [cpu.mmu.read_byte(cpu.r.s+bytes[0])]);
} else {
var memory_location = cpu.r.s + bytes[0],
low_byte = cpu.mmu.read_byte(memory_location),
high_byte = cpu.mmu.read_byte(memory_location+1);
EOR_const.execute(cpu, [low_byte, high_byte]);
}
}
}
};
var EOR_stack_relative = new cpu_lib.addressing.Stack_relative(EOR_const);
var EOR_stack_relative_indirect_indexed_y = {
bytes_required:function() {
@ -1780,28 +1778,7 @@ var ORA_absolute_indexed_y = {
var ORA_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(ORA_direct_page);
var ORA_stack_relative = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=2;
if(cpu.p.e) {
var memory_location = 0x100 | ((cpu.r.s + bytes[0]) & 0xff);
ORA_const.execute(cpu, [cpu.mmu.read_byte(memory_location)]);
} else {
if(cpu.p.m) {
ORA_const.execute(cpu, [cpu.mmu.read_byte(cpu.r.s+bytes[0])]);
} else {
var memory_location = cpu.r.s + bytes[0],
low_byte = cpu.mmu.read_byte(memory_location),
high_byte = cpu.mmu.read_byte(memory_location+1);
ORA_const.execute(cpu, [low_byte, high_byte]);
}
}
}
};
var ORA_stack_relative = new cpu_lib.addressing.Stack_relative(ORA_const);
var ORA_stack_relative_indirect_indexed_y = {
bytes_required:function() {
@ -2113,28 +2090,7 @@ var AND_absolute_indexed_y = {
var AND_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(AND_direct_page);
var AND_stack_relative = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=2;
if(cpu.p.e) {
var memory_location = 0x100 | ((cpu.r.s + bytes[0]) & 0xff);
AND_const.execute(cpu, [cpu.mmu.read_byte(memory_location)]);
} else {
if(cpu.p.m) {
AND_const.execute(cpu, [cpu.mmu.read_byte(cpu.r.s+bytes[0])]);
} else {
var memory_location = cpu.r.s + bytes[0],
low_byte = cpu.mmu.read_byte(memory_location),
high_byte = cpu.mmu.read_byte(memory_location+1);
AND_const.execute(cpu, [low_byte, high_byte]);
}
}
}
};
var AND_stack_relative = new cpu_lib.addressing.Stack_relative(AND_const);
var AND_stack_relative_indirect_indexed_y = {
bytes_required:function() {
@ -2540,28 +2496,7 @@ var CMP_absolute_indexed_y = {
}
};
var CMP_stack_relative = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cyle_count+=2;
if(cpu.p.e) {
var memory_location = 0x100 | ((cpu.r.s + bytes[0]) & 0xff);
CMP_const.execute(cpu, [cpu.mmu.read_byte(memory_location)]);
} else {
if(cpu.p.m) {
CMP_const.execute(cpu, [cpu.mmu.read_byte(cpu.r.s+bytes[0])]);
} else {
var memory_location = cpu.r.s + bytes[0],
low_byte = cpu.mmu.read_byte(memory_location),
high_byte = cpu.mmu.read_byte(memory_location+1);
CMP_const.execute(cpu, [low_byte, high_byte]);
}
}
}
};
var CMP_stack_relative = new cpu_lib.addressing.Stack_relative(CMP_const);
var CMP_stack_relative_indirect_indexed_y = {
bytes_required:function() {
@ -2965,28 +2900,7 @@ var SBC_direct_page_indirect = {
}
};
var SBC_stack_relative = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=2;
if(cpu.p.e) {
var memory_location = 0x100 | ((cpu.r.s + bytes[0]) & 0xff);
SBC_const.execute(cpu, [cpu.mmu.read_byte(memory_location)]);
} else {
if(cpu.p.m) {
SBC_const.execute(cpu, [cpu.mmu.read_byte(cpu.r.s+bytes[0])]);
} else {
var memory_location = cpu.r.s + bytes[0],
low_byte = cpu.mmu.read_byte(memory_location),
high_byte = cpu.mmu.read_byte(memory_location+1);
SBC_const.execute(cpu, [low_byte, high_byte]);
}
}
}
};
var SBC_stack_relative = new cpu_lib.addressing.Stack_relative(SBC_const);
var SBC_stack_relative_indirect_indexed_y = {
bytes_required:function() {
@ -3387,28 +3301,7 @@ var ADC_absolute_indexed_y = {
var ADC_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(ADC_direct_page);
var ADC_stack_relative = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=2;
if(cpu.p.e) {
var memory_location = 0x100 | ((cpu.r.s + bytes[0]) & 0xff);
ADC_const.execute(cpu, [cpu.mmu.read_byte(memory_location)]);
} else {
if(cpu.p.m) {
ADC_const.execute(cpu, [cpu.mmu.read_byte(cpu.r.s+bytes[0])]);
} else {
var memory_location = cpu.r.s + bytes[0],
low_byte = cpu.mmu.read_byte(memory_location),
high_byte = cpu.mmu.read_byte(memory_location+1);
ADC_const.execute(cpu, [low_byte, high_byte]);
}
}
}
};
var ADC_stack_relative = new cpu_lib.addressing.Stack_relative(ADC_const);
var ADC_stack_relative_indirect_indexed_y = {
bytes_required:function() {
@ -4508,30 +4401,6 @@ var LDA_absolute_indexed_x = {
}
};
var LDA_stack_relative = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=4;
if(cpu.p.e) {
var memory_location = 0x100 | ((cpu.r.s + bytes[0]) & 0xff);
LDA_const.execute(cpu, [cpu.mmu.read_byte(memory_location)]);
} else {
if(cpu.p.m) {
LDA_const.execute(cpu, [cpu.mmu.read_byte(cpu.r.s+bytes[0])]);
} else {
cpu.cycle_count++;
var memory_location = cpu.r.s + bytes[0],
low_byte = cpu.mmu.read_byte(memory_location),
high_byte = cpu.mmu.read_byte(memory_location+1);
LDA_const.execute(cpu, [low_byte, high_byte]);
}
}
}
};
var LDA_stack_relative_indirect_indexed_y = {
bytes_required:function() {
return 2;
@ -5433,6 +5302,8 @@ var LDA_direct_page = new cpu_lib.addressing.Direct_page(LDA_const);
var LDA_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(LDA_direct_page);
var LDA_stack_relative = new cpu_lib.addressing.Stack_relative(LDA_const);
var LDX_absolute_indexed_y = {
bytes_required: function() {
return 3;