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vic20: added cart support, fixed bugs

This commit is contained in:
Steven Hugg 2022-09-06 13:53:45 -05:00
parent 30342d2618
commit 3853f9a86a
6 changed files with 62 additions and 31 deletions
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16
presets/vic20/hellocart.dasm Normal file
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@ -0,0 +1,16 @@
processor 6502
org $a000-2 ; so we can write the ...
.word $a000 ; cartridge 2-byte header
.word Start ; start vector
.word Start ; RESTORE vector
.byte $41, $30, $c3, $c2, $cd ; "A0CBM"
Start:
lda $9004
WaitLine;
cmp $9004
beq WaitLine
sta $900f
jmp Start

1
presets/vic20/siegegame.c
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@ -205,6 +205,7 @@ void declare_winner(byte winner) {
void play_round() {
reset_players();
clrscr();
bgcolor(COLOR_BLUE);
textcolor(COLOR_WHITE);
draw_playfield();
while (1) {

BIN
res/c64.wasm
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BIN
res/vic20.wasm
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67
src/machine/vic20.ts
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@ -1,6 +1,10 @@
//// WASM Machine
// http://www.zimmers.net/anonftp/pub/cbm/documents/chipdata/VIC-I.txt
// http://www.zimmers.net/anonftp/pub/cbm/maps/Vic20.MemoryMap.txt
// http://sleepingelephant.com/denial/wiki/index.php/Autostart
import { Machine } from "../common/baseplatform";
import { Probeable, TrapCondition } from "../common/devices";
import { KeyFlags } from "../common/emu";
@ -10,7 +14,7 @@ import { BaseWASMMachine } from "../common/wasmplatform";
export class VIC20_WASMMachine extends BaseWASMMachine implements Machine, Probeable {
numTotalScanlines = 312;
cpuCyclesPerLine = 63;
cpuCyclesPerLine = 71;
videoOffsetBytes = -24 * 4;
prgstart : number;
@ -30,42 +34,47 @@ export class VIC20_WASMMachine extends BaseWASMMachine implements Machine, Probe
}
// load rom
if (this.romptr && this.romlen) {
let rom = this.romarr;
this.exports.machine_load_rom(this.sys, this.romptr, this.romlen);
this.prgstart = this.romarr[0] + (this.romarr[1]<<8); // get load address
// look for BASIC program start
if (this.prgstart == 0x1001) {
this.prgstart = this.romarr[2] + (this.romarr[3]<<8) + 2; // point to after BASIC program
console.log("prgstart", hex(this.prgstart));
}
// is program loaded into RAM?
if (this.prgstart < 0x8000) {
// advance BIOS a few frames
this.exports.machine_exec(this.sys, 400000);
// type in command (SYS 2061)
var cmd = "SYS "+this.prgstart+"\r";
console.log(cmd);
for (var i=0; i<cmd.length; i++) {
var key = cmd.charCodeAt(i);
this.exports.machine_exec(this.sys, 20000);
this.exports.machine_exec(this.sys, 20000);
this.exports.machine_key_down(this.sys, key);
this.exports.machine_exec(this.sys, 20000);
this.exports.machine_exec(this.sys, 20000);
this.exports.machine_key_up(this.sys, key);
let iscart = rom[4+2]==0x41 && rom[5+2]==0x30 && rom[6+2]==0xC3 && rom[7+2]==0xC2 && rom[8+2]==0xCD;
if (!iscart) {
this.prgstart = rom[0] + (rom[1]<<8); // get load address
// look for BASIC program start
if (this.prgstart == 0x1001) {
this.prgstart = rom[2] + (rom[3]<<8) + 2; // point to after BASIC program
console.log("prgstart", hex(this.prgstart));
}
// advance clock until program starts
for (var i=0; i<10000 && this.getPC() != this.prgstart; i++) {
//this.exports.machine_tick(this.sys);
// is program loaded into RAM?
if (this.prgstart < 0x8000) {
// advance BIOS a few frames
this.exports.machine_exec(this.sys, 500000);
// type in command (SYS 2061)
var cmd = "SYS "+this.prgstart+"\r";
console.log(cmd);
for (var i=0; i<cmd.length; i++) {
var key = cmd.charCodeAt(i);
this.exports.machine_exec(this.sys, 10000);
this.exports.machine_exec(this.sys, 10000);
this.exports.machine_key_down(this.sys, key);
this.exports.machine_exec(this.sys, 10000);
this.exports.machine_exec(this.sys, 10000);
this.exports.machine_key_up(this.sys, key);
}
// advance clock until program starts
for (var i=0; i<10000 && this.getPC() != this.prgstart; i++) {
this.exports.machine_tick(this.sys);
}
}
} else {
// get out of reset
this.exports.machine_exec(this.sys, 100);
//this.exports.machine_exec(this.sys, 100);
// wait until cartridge start
// TODO: detect ROM cartridge
var warmstart = this.romarr[0x4] + this.romarr[0x5]*256;
for (var i=0; i<150000 && this.getPC() != warmstart; i++) {
var warmstart = this.romarr[0x2+2] + this.romarr[0x3+2]*256;
for (var i=0; i<10000 && this.getPC() != warmstart; i++) {
this.exports.machine_tick(this.sys);
}
console.log('cart', i, hex(warmstart));
}
// TODO: shouldn't we return here @ start of frame?
// and stop probing
@ -74,7 +83,7 @@ export class VIC20_WASMMachine extends BaseWASMMachine implements Machine, Probe
advanceFrame(trap: TrapCondition) : number {
// TODO: does this sync with VSYNC?
var scanline = this.getRasterY();
var clocks = Math.floor((this.numTotalScanlines - scanline) * 19656 / this.numTotalScanlines);
var clocks = Math.floor((this.numTotalScanlines - scanline) * 22152 / this.numTotalScanlines);
var probing = this.probe != null;
if (probing) this.exports.machine_reset_probe_buffer();
clocks = super.advanceFrameClock(trap, clocks);

9
src/platform/vic20.ts
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@ -6,18 +6,23 @@ import { BaseMAME6502Platform } from "../common/mameplatform";
const VIC20_PRESETS = [
{id:'hello.dasm', name:'Hello World (ASM)'},
{id:'hellocart.dasm', name:'Hello Cartridge (ASM)'},
{id:'siegegame.c', name:'Siege Game (C)'},
];
const VIC20_MEMORY_MAP = { main:[
{name:'RAM', start:0x0000,size:0x0400,type:'ram'},
{name:'RAM', start:0x1000,size:0x1000,type:'ram'},
{name:'Cartridge ROM',start:0x8000,size:0x2000,type:'rom'},
{name:'BASIC ROM', start:0xc000,size:0x2000,type:'rom'},
{name:'BLK1 Cart ROM',start:0x2000,size:0x2000,type:'rom'},
{name:'BLK2 Cart ROM',start:0x4000,size:0x2000,type:'rom'},
{name:'BLK3 Cart ROM',start:0x6000,size:0x2000,type:'rom'},
{name:'Character ROM',start:0x8000,size:0x1000,type:'rom'},
{name:'I/O 1', start:0x9000,size:0x0400,type:'io'},
{name:'Color RAM', start:0x9400,size:0x0400,type:'io'},
{name:'I/O 2', start:0x9800,size:0x0400,type:'io'},
{name:'I/O 3', start:0x9c00,size:0x0400,type:'io'},
{name:'BLK5 Autostart',start:0xa000,size:0x2000,type:'rom'},
{name:'BASIC ROM', start:0xc000,size:0x2000,type:'rom'},
{name:'KERNAL ROM', start:0xe000,size:0x2000,type:'rom'},
] }