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65816.js
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move common addressing functionality for absolute indexed y 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 16:56:57 -05:00
parent 19e50d4bf7
commit 1fd918801a
1 changed files with 33 additions and 139 deletions
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172
cpu.js
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@ -87,6 +87,22 @@ var cpu_lib = {
memory_location>>8]);
};
},
Absolute_indexed_y: function(absolute_instruction) {
this.bytes_required = function() {
return 3;
};
this.execute = function(cpu, bytes) {
var initial_location = (bytes[1]<<8)|bytes[0],
memory_location = initial_location+cpu.r.y;
if((memory_location&0xff00)!==(initial_location&0xff00))
cpu.cycle_count++;
absolute_instruction.execute(cpu, [memory_location&0xff,
memory_location>>8]);
};
},
Direct_page_indexed_x: function(direct_page_instruction) {
this.bytes_required = function() {
return 2;
@ -1409,20 +1425,8 @@ var EOR_direct_page_indirect_indexed_y = {
var EOR_absolute_indexed_x =
new cpu_lib.addressing.Absolute_indexed_x(EOR_absolute);
var EOR_absolute_indexed_y = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var original_location = (bytes[1]<<8)|bytes[0],
memory_location = original_location+cpu.r.y;
if((original_location&0xff00)!==(memory_location&0xff00))
cpu.cycle_count++;
EOR_absolute.execute(cpu, [memory_location&0x00ff, memory_location>>8]);
}
};
var EOR_absolute_indexed_y =
new cpu_lib.addressing.Absolute_indexed_y(EOR_absolute);
var EOR_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(EOR_direct_page);
@ -1707,20 +1711,8 @@ var ORA_direct_page_indirect_indexed_y = {
var ORA_absolute_indexed_x =
new cpu_lib.addressing.Absolute_indexed_x(ORA_absolute);
var ORA_absolute_indexed_y = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var original_location = (bytes[1]<<8)|bytes[0],
memory_location = original_location+cpu.r.y;
if((original_location&0xff00)!==(memory_location&0xff00))
cpu.cycle_count++;
ORA_absolute.execute(cpu, [memory_location&0xff, memory_location>>8]);
}
};
var ORA_absolute_indexed_y =
new cpu_lib.addressing.Absolute_indexed_y(ORA_absolute);
var ORA_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(ORA_direct_page);
@ -2007,20 +1999,8 @@ var AND_direct_page_indirect_indexed_y = {
var AND_absolute_indexed_x =
new cpu_lib.addressing.Absolute_indexed_x(AND_absolute);
var AND_absolute_indexed_y = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var original_location = (bytes[1]<<8)|bytes[0],
memory_location = original_location+cpu.r.y;
if((original_location&0xff00)!==(memory_location&0xff00))
cpu.cycle_count++;
AND_absolute.execute(cpu, [memory_location&0x00ff, memory_location>>8]);
}
};
var AND_absolute_indexed_y =
new cpu_lib.addressing.Absolute_indexed_y(AND_absolute);
var AND_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(AND_direct_page);
@ -2404,20 +2384,8 @@ var CMP_absolute_long_indexed_x = {
var CMP_absolute_indexed_x =
new cpu_lib.addressing.Absolute_indexed_x(CMP_absolute);
var CMP_absolute_indexed_y = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var original_location = (bytes[1]<<8)|bytes[0],
memory_location = original_location+cpu.r.y;
if((original_location&0xff00)!==(memory_location&0xff00))
cpu.cycle_count++;
CMP_absolute.execute(cpu, [memory_location&0x00ff, memory_location>>8]);
}
};
var CMP_absolute_indexed_y =
new cpu_lib.addressing.Absolute_indexed_y(CMP_absolute);
var CMP_stack_relative = new cpu_lib.addressing.Stack_relative(CMP_const);
@ -2771,20 +2739,8 @@ var SBC_direct_page_indirect_indexed_y = {
var SBC_absolute_indexed_x =
new cpu_lib.addressing.Absolute_indexed_x(SBC_absolute);
var SBC_absolute_indexed_y = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var original_location = (bytes[1]<<8)|bytes[0];
var memory_location = original_location+cpu.r.y;
if((original_location&0xff00)!==(memory_location&0xff00))
cpu.cycle_count++;
SBC_absolute.execute(cpu, [memory_location&0x00ff, memory_location>>8]);
}
};
var SBC_absolute_indexed_y =
new cpu_lib.addressing.Absolute_indexed_y(SBC_absolute);
var SBC_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(SBC_direct_page);
@ -3175,24 +3131,8 @@ var ADC_direct_page_indirect_indexed_y = {
var ADC_absolute_indexed_x =
new cpu_lib.addressing.Absolute_indexed_x(ADC_absolute);
var ADC_absolute_indexed_y = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var initial_location = (bytes[1]<<8)|bytes[0],
memory_location = initial_location+cpu.r.y;
// Add 1 cycle if page boundary crossed
if((memory_location&0xff00)!==(initial_location&0xff00))
cpu.cycle_count+=3;
else
cpu.cycle_count+=2;
ADC_absolute.execute(cpu, [memory_location & 0x00ff,
memory_location >> 8]);
}
};
var ADC_absolute_indexed_y =
new cpu_lib.addressing.Absolute_indexed_y(ADC_absolute);
var ADC_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(ADC_direct_page);
@ -4245,32 +4185,6 @@ var LDA_direct_page_indirect_indexed_y = {
}
};
var LDA_absolute_indexed_y = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=4;
var original_location = (bytes[1]<<8)|bytes[0],
memory_location = original_location+cpu.r.y;
if((original_location&0xff00)!==(memory_location&0xff00))
cpu.cycle_count++;
if(cpu.p.e||cpu.p.m) {
cpu.r.a = cpu.mmu.read_byte(memory_location);
cpu.p.n = cpu.r.a >> 7;
} else {
cpu.cycle_count++;
cpu.r.a = cpu.mmu.read_word(memory_location);
cpu.p.n = cpu.r.a >> 15;
}
cpu_lib.r.p.check_z(cpu, cpu.r.a);
}
};
var LDA_stack_relative_indirect_indexed_y = {
bytes_required:function() {
return 2;
@ -5177,33 +5091,13 @@ var LDA_absolute = new cpu_lib.addressing.Absolute(LDA_const);
var LDA_absolute_indexed_x =
new cpu_lib.addressing.Absolute_indexed_x(LDA_absolute);
var LDA_absolute_indexed_y =
new cpu_lib.addressing.Absolute_indexed_y(LDA_absolute);
var LDA_stack_relative = new cpu_lib.addressing.Stack_relative(LDA_const);
var LDX_absolute_indexed_y = {
bytes_required: function() {
return 3;
},
execute: function(cpu, bytes) {
cpu.cycle_count+=4;
var original_location = (bytes[1]<<8)|bytes[0],
memory_location = original_location+cpu.r.y;
if((original_location&0xff00)!==(memory_location&0xff00))
cpu.cycle_count++;
if(cpu.p.e||cpu.p.x) {
cpu.r.x = cpu.mmu.read_byte(memory_location);
cpu.p.n = cpu.r.x >> 7;
} else {
cpu.cycle_count++;
cpu.r.x = cpu.mmu.read_word(memory_location);
cpu.p.n = cpu.r.x >> 15;
}
cpu_lib.r.p.check_z(cpu, cpu.r.x);
}
};
var LDX_absolute_indexed_y =
new cpu_lib.addressing.Absolute_indexed_y(LDX_absolute);
var LDA_absolute_long = {
bytes_required: function() {