@springfield/radio-module-baofeng/dist/shared/codecs/baofeng-decoder.js

Radio module for Baofeng UV-5R series ham radios

import { Frequency, RadioToneType } from "@springfield/ham-radio-api";
import { dcsValues } from "./baofeng-dcs-tones.js";
export class BaofengDecoder {
    config;
    logger;
    constructor(config, logger) {
        this.config = config;
        this.logger = logger;
    }
    decode(memory) {
        const radioProgram = {
            channels: [],
            settings: {},
        };
        for (let channelNumber = 0; channelNumber < this.config.numberChannels; channelNumber += 1) {
            this.logger.debug(`Decoding channel: ${channelNumber}`);
            const channelAddress = this.getChannelAddress(channelNumber);
            if (memory.contents[channelAddress] !== 0xFF) {
                const channel = this.decodeChannel(memory, channelAddress, channelNumber);
                radioProgram.channels.push(channel);
            }
        }
        return radioProgram;
    }
    getChannelAddress(channelNumber) {
        return channelNumber * this.config.channelSize;
    }
    decodeChannel(memory, channelAddress, channelNumber) {
        const transmitPower = this.decodePower(memory.contents[channelAddress + this.config.powerOffset]);
        const name = this.decodeChannelName(channelNumber, memory);
        const receiveFrequency = this.decodeFrequency(memory.contents, channelAddress, this.config.receiveFrequencyOffset);
        const transmitFrequency = this.decodeFrequency(memory.contents, channelAddress, this.config.transmitFrequencyOffset);
        const receiveTone = this.decodeTone(memory.contents, channelAddress, this.config.receiveToneOffset);
        const transmitTone = this.decodeTone(memory.contents, channelAddress, this.config.transmitToneOffset);
        const radioChannel = { name, receiveFrequency, receiveTone, transmitFrequency, transmitTone };
        const radioSpecificChannelSettings = { transmitPower };
        return { channelNumber, radioChannel, settings: radioSpecificChannelSettings };
    }
    decodePower(power) {
        return power === 0x0 ? 5 : 1;
    }
    decodeChannelName(channelNumber, memory) {
        // Channel names start at 0x1000 and each name is 16 bytes apart (0x10 offset)
        const channelNameAddress = 0x1000 + (channelNumber * 0x10);
        let channelName = "";
        // Read 7 characters (8th byte should be 0xFF terminator)
        for (let index = 0; index < 7; index += 1) {
            const value = memory.contents[channelNameAddress + index];
            if (value !== 0xFF && value !== 0x00) {
                channelName += String.fromCodePoint(value);
            }
        }
        return channelName.trim();
    }
    decodeFrequency(memoryData, channelOffset, valueOffset) {
        let value = 0;
        for (let index = 0; index < 4; index += 1) {
            value |= memoryData[channelOffset + valueOffset + index] << (8 * index);
        }
        return Frequency(Number.parseInt(value.toString(16), 10) * 10);
    }
    decodeTone(memoryData, channelOffset, valueOffset) {
        // DCS: 1 byte index, CTCSS: 2 bytes value
        const dcsIndex = memoryData[channelOffset + valueOffset];
        const ctcssValue = (memoryData[channelOffset + valueOffset] & 0xFF) | (memoryData[channelOffset + valueOffset + 1] << 8);
        // Heuristic: if the second byte is 0, treat as DCS (index), else CTCSS
        if (memoryData[channelOffset + valueOffset + 1] === 0) {
            const dcs = dcsValues[dcsIndex] ?? 0;
            return { tone: dcs, type: RadioToneType.DCS };
        }
        return { tone: ctcssValue, type: RadioToneType.CTCSS };
    }
}