modbus_ASCII
协议
2025-07-09
一个简单的modbus ASCII协议示例。 在ws 客户端 和 串口助手 上使用， 步骤（协议->下拉->配置->上传->选中目标JS文件）
// MODBUS LRC校验计算
function calculateLRC(data) {
let lrc = 0;
for (let i = 0; i < data.length; i++)
lrc += data[i];
return (~lrc + 1) & 0xff;
}
function hexToAscii(val, lowercase) {
if (val >= 0 && val <= 9)
{
return 0x30 + val;
}
else if (val >= 10 && val <= 15)
{
return (lowercase ? 0x61 : 0x41) + (val - 10);
}
return '\0'; // 非法值返回空字符
}
function byteToAscii(frame) {
const byte = new Uint8Array(frame.length * 2 + 3);
byte[0] = 0x3a;
for (let i = 0; i < frame.length; i++) {
byte[1 + 2*i] = hexToAscii((frame[i] &0xf0) >> 4, 0);
byte[2 + 2*i] = hexToAscii((frame[i] &0xf), 0);
}
byte[frame.length * 2 + 1] = 0x0d;
byte[frame.length * 2 + 2] = 0x0a;
return byte;
}
function serialize(str) {
// 尝试解析JSON格式
const modbusCmd = JSON.parse(str);
switch (modbusCmd.functionCode) {
case 1:
case 2:
case 5:
case 3:
case 4:
case 6:
// 创建MODBUS请求帧
if (1) {
const frame = new Uint8Array(7);
frame[0] = modbusCmd.slaveId; // 设备ID
frame[1] = modbusCmd.functionCode; // 功能码
frame[2] = (modbusCmd.address >> 8) & 0xFF; // 寄存器地址高字节
frame[3] = modbusCmd.address & 0xFF; // 寄存器地址低字节
frame[4] = (modbusCmd.number >> 8) & 0xFF; // 寄存器数量高字节
frame[5] = modbusCmd.number & 0xFF; // 寄存器数量低字节
frame[6] = calculateLRC(frame.slice(0, 6));
return byteToAscii(frame);
}
break;
case 15:
case 16:
if (1) {
const frame = new Uint8Array(8 + modbusCmd.bytes);
frame[0] = modbusCmd.slaveId; // 设备ID
frame[1] = modbusCmd.functionCode; // 功能码
frame[2] = (modbusCmd.address >> 8) & 0xFF; // 寄存器地址高字节
frame[3] = modbusCmd.address & 0xFF; // 寄存器地址低字节
frame[4] = (modbusCmd.number >> 8) & 0xFF; // 寄存器数量高字节
frame[5] = modbusCmd.number & 0xFF; // 寄存器数量低字节
frame[6] = modbusCmd.bytes; // 写入字节数
for (let i = 0; i < modbusCmd.bytes; i++)
frame[7 + i] = modbusCmd.data[i];
frame[7 + modbusCmd.bytes] = calculateLRC(frame.slice(0, 7 + modbusCmd.bytes));
return byteToAscii(frame);
// // 计算CRC
// const crc = calculateCRC16(frame.slice(0, 7 + modbusCmd.bytes));
// frame[7 + modbusCmd.bytes] = crc & 0xFF; // CRC低字节
// frame[8 + modbusCmd.bytes] = (crc >> 8) & 0xFF;// CRC高字节
// return frame;
}
break;
default:
break;
}
}
/**
* @param {Uint8Array} array 接收缓冲区数组
* @return {number} 缓冲区数组中，能正确解析完整一包的长度
*/
function deserialize(array) {
//检索协议\n的结束标识
let len = array.findIndex(item => item == 10);
len += len >= 0 ? 1 : 0;
return len > 0 ? len : array.length;
}
function log(array, str) {
let log = '';
// console.log(array, str);
// 创建一个新的Uint8Array来存储数据
const data = new Uint8Array(array.slice(0, array.length + 1));
try {
// 使用TextDecoder解码Uint8Array
log = new TextDecoder().decode(data);
} catch (error) {
console.error('解码错误:', error);
log = '';
}
if(str === '')
return log;
try {
let regex = new RegExp(str);
return regex.test(log)? log: '';
} catch (error) {
return log
}
}
async function test(transfer) {
for (let i = 0; i < 3; i++) {
transfer(JSON.stringify({ "slaveId": 0, "functionCode": 15, "address": 0, "number": 32, "bytes": 4, "data": [0xff, 0xff, 0xff, 0xff] }))
await new Promise(resolve => setTimeout(resolve, 300));
transfer(JSON.stringify({ "slaveId": 0, "functionCode": 15, "address": 0, "number": 32, "bytes": 4, "data": [0, 0, 0, 0] }))
await new Promise(resolve => setTimeout(resolve, 300));
}
}
function customJson() {
return [
{ name: "打开全部", str: JSON.stringify({ "slaveId": 0, "functionCode": 15, "address": 0, "number": 32, "bytes": 4, "data": [0xff, 0xff, 0xff, 0xff] }), },
{ name: "关闭全部", str: JSON.stringify({ "slaveId": 0, "functionCode": 15, "address": 0, "number": 32, "bytes": 4, "data": [0, 0, 0, 0] }) },
{ name: "获取所有输出", str: JSON.stringify({ "slaveId": 0, "functionCode": 1, "address": 0, "number": 32 }) },
{ name: "获取所有输入", str: JSON.stringify({ "slaveId": 0, "functionCode": 2, "address": 0, "number": 32 }) },
{ name: "老化测试", fun: "test" },
{ name: "复位", str: JSON.stringify({"slaveId":0, "functionCode":6, "address":1, "number":1}), title: "保持寄存器修改后，需要重新上电或复位生效"},
{ name: "恢复出厂", str: JSON.stringify({"slaveId":0, "functionCode":6, "address":1, "number":2}), title: "保持寄存器修改后，需要重新上电或复位生效"},
{ name: "查询ID", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": 0, "number": 1 }) },
{ name: "查询配置", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": 2, "number": 1 }) },
{ name: "查询MAC", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": 3, "number": 3 }) },
{ name: "查询IP", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": 6, "number": 2 }) },
{ name: "查询掩码", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": 8, "number": 2 }) },
{ name: "查询网关", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": 10, "number": 2 }) },
{ name: "查询DNS", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": 12, "number": 2 }) },
{ name: "甬道0类型", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (0 * 22) + 0), "number": 1 }) },
{ name: "甬道0超时", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (0 * 22) + 1), "number": 1 }) },
{ name: "甬道0端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (0 * 22) + 2), "number": 1 }) },
{ name: "甬道0目标端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (0 * 22) + 3), "number": 1 }) },
{ name: "甬道0目标IP", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (0 * 22) + 4), "number": 2 }) },
{ name: "甬道0目标域名", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (0 * 22) + 6), "number": 16 }) },
{ name: "甬道1类型", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (1 * 22) + 0), "number": 1 }) },
{ name: "甬道1超时", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (1 * 22) + 1), "number": 1 }) },
{ name: "甬道1端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (1 * 22) + 2), "number": 1 }) },
{ name: "甬道1目标端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (1 * 22) + 3), "number": 1 }) },
{ name: "甬道1目标IP", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (1 * 22) + 4), "number": 2 }) },
{ name: "甬道1目标域名", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (1 * 22) + 6), "number": 16 }) },
{ name: "甬道2类型", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (2 * 22) + 0), "number": 1 }) },
{ name: "甬道2超时", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (2 * 22) + 1), "number": 1 }) },
{ name: "甬道2端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (2 * 22) + 2), "number": 1 }) },
{ name: "甬道2目标端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (2 * 22) + 3), "number": 1 }) },
{ name: "甬道2目标IP", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (2 * 22) + 4), "number": 2 }) },
{ name: "甬道2目标域名", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (2 * 22) + 6), "number": 16 }) },
{ name: "甬道3类型", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (3 * 22) + 0), "number": 1 }) },
{ name: "甬道3超时", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (3 * 22) + 1), "number": 1 }) },
{ name: "甬道3端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (3 * 22) + 2), "number": 1 }) },
{ name: "甬道3目标端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (3 * 22) + 3), "number": 1 }) },
{ name: "甬道3目标IP", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (3 * 22) + 4), "number": 2 }) },
{ name: "甬道3目标域名", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (3 * 22) + 6), "number": 16 }) },
{ name: "甬道4类型", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (4 * 22) + 0), "number": 1 }) },
{ name: "甬道4超时", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (4 * 22) + 1), "number": 1 }) },
{ name: "甬道4端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (4 * 22) + 2), "number": 1 }) },
{ name: "甬道4目标端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (4 * 22) + 3), "number": 1 }) },
{ name: "甬道4目标IP", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (4 * 22) + 4), "number": 2 }) },
{ name: "甬道4目标域名", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (4 * 22) + 6), "number": 16 }) },
{ name: "甬道5类型", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (5 * 22) + 0), "number": 1 }) },
{ name: "甬道5超时", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (5 * 22) + 1), "number": 1 }) },
{ name: "甬道5端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (5 * 22) + 2), "number": 1 }) },
{ name: "甬道5目标端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (5 * 22) + 3), "number": 1 }) },
{ name: "甬道5目标IP", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (5 * 22) + 4), "number": 2 }) },
{ name: "甬道5目标域名", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (5 * 22) + 6), "number": 16 }) },
{ name: "甬道6类型", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (6 * 22) + 0), "number": 1 }) },
{ name: "甬道6超时", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (6 * 22) + 1), "number": 1 }) },
{ name: "甬道6端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (6 * 22) + 2), "number": 1 }) },
{ name: "甬道6目标端口", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (6 * 22) + 3), "number": 1 }) },
{ name: "甬道6目标IP", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (6 * 22) + 4), "number": 2 }) },
{ name: "甬道6目标域名", str: JSON.stringify({ "slaveId": 0, "functionCode": 3, "address": (14 + (6 * 22) + 6), "number": 16 }) },
{ name: "设置ip", str: JSON.stringify({ "slaveId": 0, "functionCode": 16, "address": 6, "number": 2, "bytes": 4, "data": [192, 168, 1, 50] }), title: "设置ip为 192.168.1.50" },
{ name: "设置ID=3", str: JSON.stringify({ "slaveId": 0, "functionCode": 6, "address": 0, "number": 3 }) },
{ name: "设置ID=17", str: JSON.stringify({ "slaveId": 0, "functionCode": 6, "address": 0, "number": 17 }) },
// { name: "获取ip", str: JSON.stringify({"slaveId":0, "functionCode":3, "address":8, "number":4})},
// { name: "获取gw", str: JSON.stringify({"slaveId":0, "functionCode":3, "address":12, "number":4})},
// { name: "获取mask", str: JSON.stringify({"slaveId":0, "functionCode":3, "address":16, "number":4})},
// { name: "获取mac", str: JSON.stringify({"slaveId":0, "functionCode":3, "address":20, "number":6})},
// { name: "获取udp端口", str: JSON.stringify({"slaveId":0, "functionCode":3, "address":26, "number":1})},
// { name: "获取tcp服务器端口", str: JSON.stringify({"slaveId":0, "functionCode":3, "address":27, "number":1})},
{ name: "打开1", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":0, "number":0xff00})},
{ name: "打开2", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":1, "number":0xff00})},
{ name: "打开3", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":2, "number":0xff00})},
{ name: "打开4", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":3, "number":0xff00})},
{ name: "打开5", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":4, "number":0xff00})},
{ name: "打开6", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":5, "number":0xff00})},
{ name: "打开7", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":6, "number":0xff00})},
{ name: "打开8", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":7, "number":0xff00})},
{ name: "关闭1", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":0, "number":0})},
{ name: "关闭2", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":1, "number":0})},
{ name: "关闭3", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":2, "number":0})},
{ name: "关闭4", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":3, "number":0})},
{ name: "关闭5", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":4, "number":0})},
{ name: "关闭6", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":5, "number":0})},
{ name: "关闭7", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":6, "number":0})},
{ name: "关闭8", str: JSON.stringify({"slaveId":0, "functionCode":5, "address":7, "number":0})},
// { name: "获取模拟量", str: JSON.stringify({"slaveId":17, "functionCode":4, "address":0, "number":0x0002})},
];
}