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65816.js
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move common addressing functionality for direct page indirect 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 17:32:39 -05:00
parent 0f73c71a7e
commit 9398885bc2
1 changed files with 36 additions and 153 deletions
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189
cpu.js
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@ -49,6 +49,27 @@ var cpu_lib = {
}
};
},
Direct_page_indirect: function(instruction) {
this.bytes_required = function() {
return 2;
};
this.execute = function(cpu, bytes) {
cpu.cycle_count+=3;
if((cpu.r.d&0xff)!==0)
cpu.cycle_count++;
var memory_location = bytes[0] + cpu.r.d,
absolute_location = cpu.mmu.read_word(memory_location);
if(cpu.p.e||cpu.p.m) {
instruction.execute(cpu, [cpu.mmu.read_byte(absolute_location)]);
} else {
instruction.execute(cpu, [cpu.mmu.read_byte(absolute_location),
cpu.mmu.read_byte(absolute_location+1)]);
}
};
},
Absolute: function(instruction) {
this.bytes_required = function() {
return 3;
@ -1333,27 +1354,8 @@ var EOR_absolute_long_indexed_x = {
var EOR_direct_page = new cpu_lib.addressing.Direct_page(EOR_const);
var EOR_direct_page_indirect = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=3;
if((cpu.r.d&0xff)!==0)
cpu.cycle_count++;
var memory_location = bytes[0] + cpu.r.d,
absolute_location = cpu.mmu.read_word(memory_location);
if(cpu.p.e||cpu.p.m) {
EOR_const.execute(cpu, [cpu.mmu.read_byte(absolute_location)]);
} else {
var low_byte = cpu.mmu.read_byte(absolute_location),
high_byte = cpu.mmu.read_byte(absolute_location+1);
EOR_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var EOR_direct_page_indirect =
new cpu_lib.addressing.Direct_page_indirect(EOR_const);
var EOR_direct_page_indexed_x_indirect = {
bytes_required:function() {
@ -1568,27 +1570,8 @@ var ORA_absolute_long_indexed_x = {
var ORA_direct_page = new cpu_lib.addressing.Direct_page(ORA_const);
var ORA_direct_page_indirect = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=3;
if((cpu.r.d&0xff)!==0)
cpu.cycle_count++;
var memory_location = bytes[0] + cpu.r.d,
absolute_location = cpu.mmu.read_word(memory_location);
if(cpu.p.e||cpu.p.m) {
ORA_const.execute(cpu, [cpu.mmu.read_byte(absolute_location)]);
} else {
var low_byte = cpu.mmu.read_byte(absolute_location),
high_byte = cpu.mmu.read_byte(absolute_location+1);
ORA_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var ORA_direct_page_indirect =
new cpu_lib.addressing.Direct_page_indirect(ORA_const);
var ORA_direct_page_indexed_x_indirect = {
bytes_required:function() {
@ -1801,29 +1784,8 @@ var AND_absolute_long_indexed_x = {
var AND_direct_page = new cpu_lib.addressing.Direct_page(AND_const);
var AND_direct_page_indirect = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=3;
if((cpu.r.d&0xff)!==0)
cpu.cycle_count++;
var memory_location = bytes[0] + cpu.r.d,
low_byte_loc = cpu.mmu.read_byte(memory_location),
high_byte_loc = cpu.mmu.read_byte(memory_location+1),
absolute_location = (high_byte_loc<<8) | low_byte_loc;
if(cpu.p.e||cpu.p.m) {
AND_const.execute(cpu, [cpu.mmu.read_byte(absolute_location)]);
} else {
var low_byte = cpu.mmu.read_byte(absolute_location),
high_byte = cpu.mmu.read_byte(absolute_location+1);
AND_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var AND_direct_page_indirect =
new cpu_lib.addressing.Direct_page_indirect(AND_const);
var AND_direct_page_indexed_x_indirect = {
bytes_required:function() {
@ -2088,27 +2050,8 @@ var CMP_direct_page = new cpu_lib.addressing.Direct_page(CMP_const);
var CMP_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(CMP_direct_page);
var CMP_direct_page_indirect = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=3;
if((cpu.r.d&0xff)!==0)
cpu.cycle_count++;
var memory_location = bytes[0] + cpu.r.d,
absolute_location = cpu.mmu.read_word(memory_location);
if(cpu.p.e||cpu.p.m) {
CMP_const.execute(cpu, [cpu.mmu.read_byte(absolute_location)]);
} else {
var low_byte = cpu.mmu.read_byte(absolute_location),
high_byte = cpu.mmu.read_byte(absolute_location+1);
CMP_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var CMP_direct_page_indirect =
new cpu_lib.addressing.Direct_page_indirect(CMP_const);
var CMP_direct_page_indexed_x_indirect = {
bytes_required:function() {
@ -2594,27 +2537,8 @@ var SBC_absolute_indexed_y =
var SBC_direct_page_indexed_x =
new cpu_lib.addressing.Direct_page_indexed_x(SBC_direct_page);
var SBC_direct_page_indirect = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=3;
if((cpu.r.d&0xff)!==0)
cpu.cycle_count++;
var memory_location = bytes[0] + cpu.r.d,
absolute_location = cpu.mmu.read_word(memory_location);
if(cpu.p.e||cpu.p.m) {
SBC_const.execute(cpu, [cpu.mmu.read_byte(absolute_location)]);
} else {
var low_byte = cpu.mmu.read_byte(absolute_location),
high_byte = cpu.mmu.read_byte(absolute_location+1);
SBC_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var SBC_direct_page_indirect =
new cpu_lib.addressing.Direct_page_indirect(SBC_const);
var SBC_stack_relative = new cpu_lib.addressing.Stack_relative(SBC_const);
@ -2780,27 +2704,8 @@ var ADC_absolute_long_indexed_x = {
var ADC_direct_page = new cpu_lib.addressing.Direct_page(ADC_const);
var ADC_direct_page_indirect = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
if((cpu.r.d&0x00ff)!==0)
cpu.cycle_count+=4;
else
cpu.cycle_count+=3;
var memory_location = bytes[0] + cpu.r.d,
absolute_location = cpu.mmu.read_word(memory_location);
if(cpu.p.e||cpu.p.m) {
ADC_const.execute(cpu, [cpu.mmu.read_byte(absolute_location)]);
} else {
var low_byte = cpu.mmu.read_byte(absolute_location),
high_byte = cpu.mmu.read_byte(absolute_location+1);
ADC_const.execute(cpu, [low_byte, high_byte]);
}
}
};
var ADC_direct_page_indirect =
new cpu_lib.addressing.Direct_page_indirect(ADC_const);
var ADC_direct_page_indexed_x_indirect = {
bytes_required:function() {
@ -3768,31 +3673,6 @@ var STA_stack_relative_indirect_indexed_y = {
}
};
var LDA_direct_page_indirect = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
cpu.cycle_count+=5;
if((cpu.r.d&0xff)!==0)
cpu.cycle_count++;
var memory_location = bytes[0] + cpu.r.d,
absolute_location = cpu.mmu.read_word(memory_location);
if(cpu.p.e||cpu.p.m) {
cpu.r.a = cpu.mmu.read_byte(absolute_location);
cpu.p.n = cpu.r.a >> 7;
} else {
cpu.cycle_count++;
cpu.r.a = cpu.mmu.read_word(absolute_location);
cpu.p.n = cpu.r.a >> 15;
}
cpu_lib.r.p.check_z(cpu, cpu.r.a);
}
};
var LDA_direct_page_indexed_x_indirect = {
bytes_required:function() {
return 2;
@ -4777,6 +4657,9 @@ 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_direct_page_indirect =
new cpu_lib.addressing.Direct_page_indirect(LDA_const);
var LDA_absolute = new cpu_lib.addressing.Absolute(LDA_const);
var LDA_absolute_indexed_x =