6502
/
65816.js
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added TSB and both addressing modes for it

This commit is contained in:
Preston Skupinski 2011-05-30 19:55:59 -04:00
parent c9d491411b
commit 48c6fe5cf9
2 changed files with 66 additions and 3 deletions
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2
TODO
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@ -8,8 +8,6 @@ Testing:
- Tests needed for interrupt support
- Tests needed for the numerous other operations added
Operations Not Yet Implemented:
- 0x04 : TSB direct page
- 0x0c : TSB absolute
- 0x14 : TRB direct page
- 0x1c : TRB absolute
- 0x42 : WDM

67
cpu.js
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@ -208,7 +208,8 @@ function CPU_65816() {
0x02 : COP, 0x89 : BIT_const, 0x2c : BIT_absolute,
0x24 : BIT_direct_page,
0x3c : BIT_absolute_indexed_x,
0x34 : BIT_direct_page_indexed_x };
0x34 : BIT_direct_page_indexed_x,
0x0c : TSB_absolute, 0x04 : TSB_direct_page };
/**
* Take a raw hex string representing the program and execute it.
@ -424,6 +425,70 @@ var MMU = {
}
};
var TSB_absolute = {
bytes_required:function() {
return 3;
},
execute:function(cpu, bytes) {
var location = (bytes[1]<<8)|bytes[0];
if(cpu.p.e|cpu.p.m) {
var data = cpu.mmu.read_byte(location);
if((data & cpu.r.a) === 0) {
cpu.p.z = 1;
} else {
cpu.p.z = 0;
}
cpu.mmu.store_byte(location, (cpu.r.a | data));
} else {
var low_byte = cpu.mmu.read_byte(location);
var high_byte = cpu.mmu.read_byte((location+1)&0xffff);
var data = (high_byte<<8) | low_byte;
if((data & cpu.r.a) === 0) {
cpu.p.z = 1;
} else {
cpu.p.z = 0;
}
data |= cpu.r.a;
high_byte = data >> 8;
low_byte = data & 0xff;
cpu.mmu.store_byte(location, low_byte);
cpu.mmu.store_byte((location+1)&0xffff, high_byte);
}
}
};
var TSB_direct_page = {
bytes_required:function() {
return 2;
},
execute:function(cpu, bytes) {
var location = bytes[0] + cpu.r.d;
if(cpu.p.e|cpu.p.m) {
var data = cpu.mmu.read_byte(location&0xffff);
if((data & cpu.r.a) === 0) {
cpu.p.z = 1;
} else {
cpu.p.z = 0;
}
cpu.mmu.store_byte(location&0xffff, (cpu.r.a | data));
} else {
var low_byte = cpu.mmu.read_byte(location&0xffff);
var high_byte = cpu.mmu.read_byte((location+1)&0xffff);
var data = (high_byte<<8) | low_byte;
if((data & cpu.r.a) === 0) {
cpu.p.z = 1;
} else {
cpu.p.z = 0;
}
data |= cpu.r.a;
high_byte = data >> 8;
low_byte = data & 0xff;
cpu.mmu.store_byte(location&0xffff, low_byte);
cpu.mmu.store_byte((location+1)&0xffff, high_byte);
}
}
};
var BIT_const = {
bytes_required:function(cpu) {
if(cpu.p.e|cpu.p.m)