蓝牙通讯初步调通

utils/w13Packet.js

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+// W13 BLE 协议公共组包模块
+// 导出通用的组包构造与CRC16计算（支持 CCITT-FALSE 与 MODBUS）
+
+const DEFAULT_HEAD = [0xCC, 0xC0];
+const MAX_LEN = 548; // 文档声明的最大总长度（含包头与CRC）
+
+export const COMMANDS = {
+  READ_VERSION: 0x01,
+  SET_CONDITION_1: 0x08,
+  SET_CONDITION_2: 0x09,
+  OTA_START: 0x0B,
+  ENABLE_BLE_LOG: 0x0C,
+  RADAR_STATUS: 0x11,
+  TEST_KEYS: 0x13,
+};
+
+function toUint16LE(v) {
+  const x = v & 0xFFFF;
+  return [x & 0xFF, (x >>> 8) & 0xFF];
+}
+
+function ensureUint8Array(data) {
+  if (!data) return new Uint8Array(0);
+  if (data instanceof Uint8Array) return data;
+  if (Array.isArray(data)) return Uint8Array.from(data.map(x => x & 0xFF));
+  if (typeof data === 'string') {
+    // 默认按ASCII编码；如需GBK请先外部转换后传入字节数组
+    const arr = new Uint8Array(data.length);
+    for (let i = 0; i < data.length; i++) arr[i] = data.charCodeAt(i) & 0xFF;
+    return arr;
+  }
+  throw new TypeError('Unsupported payload type');
+}
+
+// CRC-16/CCITT-FALSE: poly=0x1021, init=0xFFFF, refin=false, refout=false, xorout=0x0000
+export function crc16Ccitt(bytes, start = 0, end = bytes.length) {
+  let crc = 0xFFFF;
+  for (let i = start; i < end; i++) {
+    crc ^= (bytes[i] << 8);
+    for (let j = 0; j < 8; j++) {
+      if (crc & 0x8000) crc = (crc << 1) ^ 0x1021; else crc <<= 1;
+      crc &= 0xFFFF;
+    }
+  }
+  return crc & 0xFFFF;
+}
+
+// CRC-16/MODBUS: poly=0xA001, init=0xFFFF, refin=true, refout=true, xorout=0x0000
+export function crc16Modbus(bytes, start = 0, end = bytes.length) {
+  let crc = 0xFFFF;
+  for (let i = start; i < end; i++) {
+    crc ^= bytes[i];
+    for (let j = 0; j < 8; j++) {
+      const lsb = crc & 0x0001;
+      crc >>= 1;
+      if (lsb) crc ^= 0xA001;
+    }
+  }
+  return crc & 0xFFFF;
+}
+
+function computeCrc(bytes, type, range) {
+  const [start, end] = range || [0, bytes.length];
+  if (type === 'MODBUS') return crc16Modbus(bytes, start, end);
+  return crc16Ccitt(bytes, start, end);
+}
+
+/**
+ * 构造W13协议数据帧
+ * 字段：Head(2) + Len(2) + CRC(2) + Frame(2) + FramNum(2) + Frame_Type(1) + Parameters(N)
+ * Len为整包总长度（含Head与CRC），小端；CRC16默认CCITT-FALSE，计算范围为整包除CRC字段自身。
+ *
+ * @param {Object} opts
+ * @param {number} opts.frame 帧号(0~65535)
+ * @param {number} opts.framNum 帧总数(0~65535)
+ * @param {number} opts.type 命令字(0~255)
+ * @param {Uint8Array|number[]|string} [opts.params] 参数字节或ASCII字符串
+ * @param {('CCITT'|'MODBUS')} [opts.crcType] CRC算法选择，默认CCITT
+ * @param {number[]} [opts.head] 包头，默认[0xCC,0xC0]
+ * @returns {Uint8Array}
+ */
+export function buildPacket(opts) {
+  const head = (opts && opts.head) || DEFAULT_HEAD;
+  const frame = (opts && opts.frame) != null ? (opts.frame >>> 0) : 1;
+  const framNum = (opts && opts.framNum) != null ? (opts.framNum >>> 0) : 1;
+  const type = (opts && opts.type) != null ? (opts.type & 0xFF) : 0x00;
+  const params = ensureUint8Array(opts && opts.params);
+  const crcType = (opts && opts.crcType) === 'MODBUS' ? 'MODBUS' : 'CCITT';
+
+  // 预分配：固定头(2) + 长度(2) + CRC(2) + Frame(2) + FramNum(2) + Type(1) + 参数
+  const fixedLen = 2 + 2 + 2 + 2 + 2 + 1;
+  const totalLen = fixedLen + params.length;
+  if (totalLen > MAX_LEN) throw new RangeError(`Packet too long: ${totalLen} > ${MAX_LEN}`);
+
+  const buf = new Uint8Array(totalLen);
+  let off = 0;
+
+  // Head
+  buf[off++] = head[0] & 0xFF;
+  buf[off++] = head[1] & 0xFF;
+
+  // Len (占位后写入)
+  const lenLE = toUint16LE(totalLen);
+  buf[off++] = lenLE[0];
+  buf[off++] = lenLE[1];
+
+  // CRC (占位，稍后计算写入)
+  const crcPos = off;
+  buf[off++] = 0x00;
+  buf[off++] = 0x00;
+
+  // Frame
+  const frameLE = toUint16LE(frame);
+  buf[off++] = frameLE[0];
+  buf[off++] = frameLE[1];
+
+  // FramNum
+  const framNumLE = toUint16LE(framNum);
+  buf[off++] = framNumLE[0];
+  buf[off++] = framNumLE[1];
+
+  // Frame_Type
+  buf[off++] = type;
+
+  // Parameters
+  buf.set(params, off);
+
+  // 计算CRC：整包除CRC字段自身
+  // 为避免实现差异，计算时将CRC位置的两个字节视为0
+  buf[crcPos] = 0x00;
+  buf[crcPos + 1] = 0x00;
+  const crc = computeCrc(buf, crcType, [0, buf.length]);
+  const crcLE = toUint16LE(crc);
+  buf[crcPos] = crcLE[0];
+  buf[crcPos + 1] = crcLE[1];
+
+  return buf;
+}
+
+/**
+ * 便捷构造：使用命令常量与简易参数数组
+ * @param {number} cmd COMMANDS中的命令字
+ * @param {number[]|Uint8Array|string} payload 参数
+ * @param {{frame?:number, framNum?:number, crcType?:('CCITT'|'MODBUS'), head?:number[]}} [options]
+ */
+export function buildCommand(cmd, payload, options = {}) {
+  return buildPacket({
+    frame: options.frame != null ? options.frame : 1,
+    framNum: options.framNum != null ? options.framNum : 1,
+    type: cmd & 0xFF,
+    params: payload,
+    crcType: options.crcType === 'MODBUS' ? 'MODBUS' : 'CCITT',
+    head: options.head || DEFAULT_HEAD,
+  });
+}
+
+/**
+ * 示例：构造“读版本号”命令帧 (Frame_Type=0x01, P0=0x00)
+ * @returns {Uint8Array}
+ */
+export function buildReadVersion() {
+  return buildCommand(COMMANDS.READ_VERSION, [0x00]);
+}