vgm-conv/dist/converter/ay8910-clock-converter.js

Chip-type and clock converter for VGM.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.AY8910ClockConverter = void 0;
const vgm_converter_1 = require("./vgm-converter");
const vgm_parser_1 = require("vgm-parser");
class AY8910ClockConverter extends vgm_converter_1.VGMClockConverter {
    _ratio;
    _regs = new Uint8Array(16);
    _outRegs = new Int16Array(16);
    constructor(from, toClock, opts) {
        super(from, toClock, 3579545 / 2);
        this._ratio = this.to.clock / from.clock;
        for (let i = 0; i < this._outRegs.length; i++) {
            this._outRegs[i] = -1;
        }
    }
    convertWriteDataCommand(cmd) {
        const { addr, data } = cmd;
        if (this._ratio !== 1.0 && 0 <= addr && addr < 16) {
            this._regs[addr] = data;
            if (addr < 6) {
                // freq
                const ah = addr | 1;
                const al = addr & 6;
                const raw = ((this._regs[ah] & 0x0f) << 8) | this._regs[al];
                const adj = Math.min(0x0fff, Math.round(raw * this._ratio));
                return [cmd.copy({ addr: al, data: adj & 0xff }), cmd.copy({ addr: ah, data: adj >> 8 })];
            }
            else if (addr === 6) {
                // noise freq
                const raw = this._regs[6] & 0x1f;
                const adj = Math.min(0x1f, Math.round(raw * this._ratio));
                return [cmd.copy({ data: adj })];
            }
            else if (addr == 11 || addr == 12) {
                // envelope freq
                const ah = 12;
                const al = 11;
                const raw = (this._regs[ah] << 8) | this._regs[al];
                const adj = Math.min(0xffff, Math.round(raw * this._ratio));
                return [cmd.copy({ addr: al, data: adj & 0xff }), cmd.copy({ addr: ah, data: adj >> 8 })];
            }
        }
        return [cmd];
    }
    convertCommand(cmd) {
        if (cmd instanceof vgm_parser_1.VGMWriteDataCommand && cmd.chip === this.from.chip && cmd.index === this.from.index) {
            return this.convertWriteDataCommand(cmd);
        }
        return [cmd];
    }
}
exports.AY8910ClockConverter = AY8910ClockConverter;