1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
|
import The65c02, { BitField, Pin } from "./65c02.ts";
import matrix from "./opcode_matrix.json" with { type: "json" };
import { parseArgs } from "jsr:@std/cli/parse-args";
// the thing used for ram
const ram = new Uint8Array(2**16);
// initiate the emulator
const cpu = new The65c02(function (this: The65c02) {
// since this is controlled by the user it's easy
// to map things into address space
this.io.data.set(ram[this.io.address.num()] ?? 0)
}, function (this: The65c02) {
// write
ram[this.io.address.num()] = this.io.data.num()
})
await cpu.loadInstructions()
const args = parseArgs(Deno.args)
const binStart = parseInt(args.b ?? args.binStart ?? '8000', 16)
if (Number.isNaN(binStart))
throw 'binStart is NaN!'
// mem address $0000
ram[0xFFFC] = binStart & 0x00FF
ram[0xFFFD] = binStart & 0xFF00
// read code from file
const code = Deno.readFileSync(args._.toString() || 'msbasic/tmp/eater.bin')
// write code to ram before execution
for (let offset = 0; offset < code.length; offset++) {
const byte = code[offset];
ram[binStart + offset] = byte;
}
// pull RESB low to reset the 65c02
cpu.io.reset.LO()
cpu.cycle()
//the cpu reset, pull RESB high and start execution!
cpu.io.reset.HI()
function inspect() {
console.log('IO status:')
console.log(Object.entries(cpu.io)
.map(([name, io]) => {
if (io instanceof Pin) {
return ` ${name}: ${' '.repeat(20 - name.length)}${io.high ? "HI" : "LO"}`
} else if (io instanceof BitField) {
return ` ${name}: ${' '.repeat(20 - name.length)}${io.bits.map(k=>+k).join('')} (0x${io.num().toString(16)})`
}
}).join('\n'));
console.log('\nregisters:')
console.log(` A: ${cpu.regA.bits.map(k=>+k).join('')} (0x${cpu.regA.num().toString(16)})`)
console.log(` X: ${cpu.regX.bits.map(k=>+k).join('')} (0x${cpu.regX.num().toString(16)})`)
console.log(` Y: ${cpu.regY.bits.map(k=>+k).join('')} (0x${cpu.regY.num().toString(16)})`)
console.log(` SP: ${cpu.stackPointer.bits.map(k=>+k).join('')} (0x${cpu.stackPointer.num().toString(16)})`)
console.log(` PC: ${cpu.programCounter.bits.map(k=>+k).join('')} (0x${cpu.programCounter.num().toString(16)})`)
}
const debug = Deno.args.includes('-d')
let skip = 0;
let breakpoints: number[] = []
let instBreakpoints: string[] = []
// repeat until the cpu requests an interrupt
while (!cpu.io.interruptRequest.high) {
const instId = ram[cpu.programCounter.num()]
.toString(16)
.padStart(2, '0');
const goog = (matrix as Record<string, { mnemonic: string, mode: string }>)[instId];
if (!goog) {
console.log('uh', instId, 'unknown')
break;
}
const instr = goog;
console.debug(cpu.programCounter.num().toString(16).padStart(4, '0'),instr.mnemonic, instr.mode)
cpu.cycle();
// debug step-by-step mode
dbg: if (debug) {
if (instBreakpoints.includes(instr.mnemonic)) {
instBreakpoints = instBreakpoints.filter(k => k != instr.mnemonic)
skip = 0;
console.log('hit instruction breakpoint on', cpu.programCounter.num().toString(16))
}
if (breakpoints.includes(cpu.programCounter.num())) {
breakpoints = breakpoints.filter(k => k != cpu.programCounter.num())
skip = 0;
console.log('hit breakpoint on', cpu.programCounter.num().toString(16))
}
if (skip > 0) {
skip--
break dbg;
}
const i = new Uint8Array(8);
Deno.stdout.write(Uint8Array.from(['.'.charCodeAt(0)]))
await Deno.stdin.read(i);
if (i[0] == 'b'.charCodeAt(0)) {
console.log('BREAK!!')
break;
} else if (i[0] == 'i'.charCodeAt(0)) {
inspect()
} else if (i[0] == 's'.charCodeAt(0)) {
console.log('stack:')
for (let i = 0; i < cpu.stackPointer.num(); i++) {
console.log(` ${i.toString(16).padStart(2, '0')} ${ram[0x01FF - i].toString(2).padStart(8, '0')} (0x${ram[0x01FF - i].toString(16).padStart(4, '0')} ${ram[0x01FF - i].toString().padStart(3)})`)
}
} else if (i[0] == 'k'.charCodeAt(0)) {
const num = +(new TextDecoder().decode(i.slice(1, 7)).replaceAll('\0', ''));
if (Number.isNaN(num)) {
console.log('NaN')
break dbg;
}
skip = num;
console.log(`skipping ${num} cycles`)
} else if (i[0] == 'r'.charCodeAt(0)) {
const num = i[2] ? parseInt(new TextDecoder().decode(i.slice(1, 7)).replace('\n', '').replaceAll('\0', ''), 16) : cpu.programCounter.num();
console.log(`set breakpoint on`, num.toString(16))
breakpoints.push(num)
} else if (i[0] == '?'.charCodeAt(0)) {
console.log(`b - break, exit
i - inspect
s - inspect stack
k[NUM] - skip
r[ADR] - breakpoint
g[ADR] - goto, change PC
I[INS] - breakpoint instruction`);
} else if (i[0] == 'g'.charCodeAt(0)) {
const num = i[2] ? parseInt(new TextDecoder().decode(i.slice(1, 7)).replace('\n', '').replaceAll('\0', ''), 16) : cpu.programCounter.num();
console.log(`PC set to`, num.toString(16))
cpu.programCounter.set(num)
} else if (i[0] == 'I'.charCodeAt(0)) {
const instr = new TextDecoder().decode(i.slice(1, 7)).replace('\n', '').replaceAll('\0', '')
console.log(`instruction breakpoint set on`, instr)
instBreakpoints.push(instr)
}
}
}
console.log('end of execution\n\n')
inspect()
// console.debug('\nRAM:')
Deno.writeFileSync('ram.bin', ram)
// new Deno.Command('hexdump', {
// args: ['-C', 'ram.bin']
// }).spawn()
|
