Vector-06c

Embedding

The core is svofski/vector06js, an original JavaScript Vector-06c emulator, running on Alexander Demin's i8080.js CPU. It is a set of plain constructors — Memory, IO, I8080, Vector06c — with no wasm heap, so everything the debugger needs is a field or method on a live object.

Boot. Wire the machine exactly like the vendored main.js, but instead of the core's self-scheduling oneFrame() loop, own a requestAnimationFrame loop that calls oneInterrupt() — one TV field (one interrupt period) per call — then displayFrame():

var memory = new Memory();
var io  = new IO(keyboard, timer, memory, ay, floppy, tape);
var cpu = new I8080(memory, io);
var v06c = new Vector06c(cpu, memory, io, ay, tape);
memory.attach_boot(bootRom);          // 2K on-board boot loader at $0000
blkSbr(true, false);                 // reset: pc=0, init the i8253, boot
(function loop(){
  v06c.oneInterrupt(true);            // run one field, or until a breakpoint
  v06c.displayFrame();
  requestAnimationFrame(loop);
})();

A .rom image loads at 00 and is entered via a NOP-slide from $0000 (sp = $C300), the way the machine's own loader launches programs.

Debugger integration

The plug-in (vector06c-debug.js) describes the machine to the shared debugger; the controllable loop lives in vector06c-machine.js:

• Registers are read live from the 8080 core each refresh (A, B, C, D, E, H, L, SP, PC, IFF and the S Z H P C flags) and written straight back through set_reg and the flag fields.
• Disassembly uses the shared z80 decoder: the Z80 is a superset of the 8080, so it renders KR580VM80A code correctly, mnemonics and all.
• Memory is the full 64 KB CPU view plus the 2 KB boot-ROM overlay, read side-effect-free.
• Single step is one cpu.instruction(). Breakpoints reuse the core's own once-per-instruction hook (v06c.dbg.check_breakpoint()) against a PC set. Write watchpoints wrap Memory.write — the one path every CPU store passes through — and pause on a store to a watched address.

Architecture

The Vector-06c (Вектор-06Ц, 1987) is a Soviet home computer designed by Donat Temirazov and Alexander Sokolov. Its CPU is the KR580VM80A (КР580ВМ80А), a Soviet clone of the Intel 8080 running at 3 MHz.

• Video — a bit-plane framebuffer (four 8 KB planes) shifted through a 16-entry palette selected from 256 colours, with hardware vertical scroll and a coloured border. The palette and border can be rewritten mid-scanline, which the pixel filler models cycle-accurately.
• I/O — two KR580VV55 (Intel 8255) parallel interfaces drive the keyboard matrix, border, video mode and palette latch; a KR580VI53 (Intel 8253) timer feeds the sound; an AY-3-8910-style chip and a Covox add audio; a KR1818VG93 (FD1793) handles floppy disks.
• Memory — 64 KB RAM with a bank-switched extension (the "quasi-disk"), overlaid at reset by a 2 KB boot ROM. This build boots to Vektor BASIC by default, with the on-ROM "boots" loader and a set of raster/palette test programs as extra configurations.

Sound

The vendored core already carries a complete audio path: sound.js's Soundnik owns its own AudioContext and mixes every source of the machine — the AY-3-8910 (ay.js), the KR580VI53 (i8253) timer beeper, the Covox, and the WAV/tape player — down to a single gainNode that feeds the audio destination, driven each TV field by oneInterrupt()'s soundStep(). So there is nothing to emulate or re-route; the finished mix is already correct.

To fit the shared Sound button we simply gate that whole mix rather than any single voice. vector06c-machine.js holds a muted flag (true at boot) and an applyMute() that opens or closes the core's own gainNode and suspends/resumes its AudioContext, then exposes isMuted/setMute on the transport. It starts silent (browsers block audio before a gesture) and unmutes from the button's real click. The shared /debugger/src/audio.js sink is not loaded — the core drives its own output.

var muted = true;                       // start silent, needs a gesture
function applyMute() {
  var snd = v06c.soundnik;             // the vendored mixer
  snd.mute(muted);                    // gainNode.gain = muted ? 0 : 1 (the whole mix)
  var ac = snd.audioContext;
  muted ? ac.suspend() : ac.resume();  // gate the core's OWN context
}
transport.isMuted = function () { return muted; };
transport.setMute = function (m) { muted = !!m; applyMute(); };