visual6502/macros.js

296 lines
8.1 KiB
JavaScript

/*
Copyright (c) 2010 Brian Silverman, Barry Silverman
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
var memory = Array();
var code = [0xa9, 0x00, 0x20, 0x10, 0x00, 0x4c, 0x02, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xe8, 0x88, 0xe6, 0x40, 0x38, 0x69, 0x02, 0x60];
var cycle = 0;
var trace = Array();
var running = false;
function go(n){
for(var i=0;i<code.length;i++){
mWrite(i, code[i]);
setCellValue(i, code[i]);
}
mWrite(0xfffc, 0x00);
mWrite(0xfffd, 0x00);
steps();
}
function steps(){
if(running) {
step();
setTimeout(steps, 0); // schedule the next poll
}
}
function testNMI(n){
initChip();
mWrite(0x0000, 0x38); // set carry
mWrite(0x0001, 0x4c); // jump to test code
mWrite(0x0002, 0x06);
mWrite(0x0003, 0x23);
mWrite(0x22ff, 0x38); // set carry
mWrite(0x2300, 0xea);
mWrite(0x2301, 0xea);
mWrite(0x2302, 0xea);
mWrite(0x2303, 0xea);
mWrite(0x2304, 0xb0); // branch carry set to self
mWrite(0x2305, 0xfe);
mWrite(0x2306, 0xb0); // branch carry set to self
mWrite(0x2307, 0x01);
mWrite(0x2308, 0x00); // brk should be skipped
mWrite(0x2309, 0xa9); // anything
mWrite(0x230a, 0xde); // anything
mWrite(0x230b, 0xb0); // branch back with page crossing
mWrite(0x230c, 0xf2);
mWrite(0xc018, 0x40); // nmi handler
mWrite(0xfffa, 0x18); // nmi vector
mWrite(0xfffb, 0xc0);
mWrite(0xfffc, 0x00); // reset vector
mWrite(0xfffd, 0x00);
for(var i=0;i<n;i++){step();}
setLow('nmi');
chipStatus();
for(var i=0;i<8;i++){step();}
setHigh('nmi');
chipStatus();
for(var i=0;i<16;i++){step();}
}
function initChip(){
var start = now();
for(var nn in nodes) nodes[nn].state = 'fl';
nodes[ngnd].state = 'gnd';
nodes[npwr].state = 'vcc';
for(var tn in transistors) transistors[tn].on = false;
setLow('res');
setLow('clk0');
setHigh('rdy'); setLow('so');
setHigh('irq'); setHigh('nmi');
recalcNodeList(allNodes());
for(var i=0;i<8;i++){setHigh('clk0'), setLow('clk0');}
setHigh('res');
for(var i=0;i<18;i++){resetStep();}
refresh();
cycle = 0;
trace = Array();
chipStatus();
console.log('initChip done after', now()-start);
}
function step(){
trace[cycle]= {chip: stateString(), mem: getMem()};
halfStep();
cycle++;
chipStatus();
}
function halfStep(){
var clk = isNodeHigh(nodenames['clk0']);
if (clk) {setLow('clk0'); handleBusRead(); }
else {setHigh('clk0'); handleBusWrite();}
refresh();
}
function resetStep(){
var clk = isNodeHigh(nodenames['clk0']);
if (clk) {setLow('clk0'); handleBusRead(); }
else {setHigh('clk0'); handleBusWrite();}
}
function handleBusRead(){
if(isNodeHigh(nodenames['rw'])) writeDataBus(mRead(readAddressBus()));
}
function handleBusWrite(){
if(!isNodeHigh(nodenames['rw'])){
var a = readAddressBus();
var d = readDataBus();
mWrite(a,d);
if(a<0x200) setCellValue(a,d);
}
}
function readAddressBus(){return readBits('ab', 16);}
function readDataBus(){return readBits('db', 8);}
function readA(){return readBits('a', 8);}
function readY(){return readBits('y', 8);}
function readX(){return readBits('x', 8);}
function readP(){return readBits('p', 8);}
function readPstring(){
var result;
result = (isNodeHigh(nodenames['p7'])?'N':'n') +
(isNodeHigh(nodenames['p6'])?'V':'v') +
'-' +
(isNodeHigh(nodenames['p3'])?'B':'b') +
(isNodeHigh(nodenames['p3'])?'D':'d') +
(isNodeHigh(nodenames['p2'])?'I':'i') +
(isNodeHigh(nodenames['p1'])?'Z':'z') +
(isNodeHigh(nodenames['p0'])?'C':'c');
return result;
}
function readSP(){return readBits('s', 8);}
function readPC(){return (readBits('pch', 8)<<8) + readBits('pcl', 8);}
function readPCL(){return readBits('pcl', 8);}
function readPCH(){return readBits('pch', 8);}
function readBit(name){
return isNodeHigh(nodenames[name])?1:0;
}
function readBits(name, n){
var res = 0;
for(var i=0;i<n;i++){
var nn = nodenames[name+i];
res+=((isNodeHigh(nn))?1:0)<<i;
}
return res;
}
function writeDataBus(x){
var recalcs = Array();
for(var i=0;i<8;i++){
var nn = nodenames['db'+i];
var n = nodes[nn];
if((x%2)==0) {n.pulldown=true; n.pullup=false;}
else {n.pulldown=false; n.pullup=true;}
recalcs.push(nn);
x>>=1;
}
recalcNodeList(recalcs);
}
function mRead(a){
if(memory[a]==undefined) return 0;
else return memory[a];
}
function mWrite(a, d){memory[a]=d;}
function clkNodes(){
var res = Array();
res.push(943);
for(var i in nodes[943].gates){
var t = transistors[nodes[943].gates[i]];
if(t.c1==npwr) res.push(t.c2);
if(t.c2==npwr) res.push(t.c1);
}
hiliteNode(res);
}
function runChip(){
var start = document.getElementById('start');
var stop = document.getElementById('stop');
start.style.visibility = 'hidden';
stop.style.visibility = 'visible';
running = true;
steps();
}
function stopChip(){
var start = document.getElementById('start');
var stop = document.getElementById('stop');
start.style.visibility = 'visible';
stop.style.visibility = 'hidden';
running = false;
}
function resetChip(){
stopChip();
setStatus('resetting 6502...');
setTimeout(initChip,0);
}
function stepForward(){
stopChip();
step();
}
function stepBack(){
if(cycle==0) return;
showState(trace[--cycle].chip);
setMem(trace[cycle].mem);
var clk = isNodeHigh(nodenames['clk0']);
if(!clk) writeDataBus(mRead(readAddressBus()));
chipStatus();
}
function chipStatus(){
var ab = readAddressBus();
var machine1 =
' halfcyc:' + cycle +
' phi0:' + readBit('clk0') +
' AB:' + hexWord(ab) +
' D:' + hexByte(readDataBus()) +
' RnW:' + readBit('rw');
var machine2 =
' PC:' + hexWord(readPC()) +
' A:' + hexByte(readA()) +
' X:' + hexByte(readX()) +
' Y:' + hexByte(readY()) +
' SP:' + hexByte(readSP()) +
' ' + readPstring();
var machine3 =
' Sync:' + readBit('sync')
' IRQ:' + readBit('irq') +
' NMI:' + readBit('nmi');
var machine4 =
' IR:' + hexByte(255 - readBits('notir', 8)) +
' idl:' + hexByte(255 - readBits('idl', 8)) +
' alu:' + hexByte(255 - readBits('alu', 8)) +
' TCstate:' + readBit('clock1') + readBit('clock2') +
readBit('t2') + readBit('t3') + readBit('t4') + readBit('t5');
var machine5 =
' notRdy0:' + readBit('notRdy0') +
' fetch:' + readBit('fetch') +
' clearIR:' + readBit('clearIR') +
' D1x1:' + readBit('D1x1');
setStatus(machine1 + "<br>" + machine2);
if (loglevel>2) {
console.log(machine1 + " " + machine2 + " " + machine3 + " " + machine4 + " " + machine5);
}
selectCell(ab);
}
function getMem(){
var res = Array();
for(var i=0;i<0x200;i++) res.push(mRead(i));
return res;
}
function setMem(arr){
for(var i=0;i<0x200;i++){mWrite(i, arr[i]); setCellValue(i, arr[i]);}
}
function hexWord(n){return (0x10000+n).toString(16).substring(1)}
function hexByte(n){return (0x100+n).toString(16).substring(1)}