一、Modbus含义
Modbus是一种单主站的主/从通信模式，它定义了一种通讯规范，用于在工业自动化系统中实现设备之间的数据交换。Modbus网络上只能有一个主站存在，主站在Modbus网络上没有地址，而从站的地址范围为0-247，其中0为广播地址，从站的实际地址范围为1-247。
Modbus通信协议可以通过多种传输方式传播，如RS232C、RS485、光纤和无线电等。它具有两种串行传输模式，即ASCII和RTU，它们定义了数据如何打包和解码的方式。一般来说，支持Modbus协议的设备都会支持RTU格式，通信双方必须同时支持这两种模式中的一种。
总结来说，Modbus是一种用于工业自动化系统的通信协议，它定义了通信格式和规范，可以通过不同的传输方式进行数据交换
二、Java如何对接Modbus
1、读取数据
public class Modbus4jUtils {
/**
* 工厂。
*/
static ModbusFactory modbusFactory;
static {
if (modbusFactory == null) {
modbusFactory = new ModbusFactory();
}
}
/**
* 获取master
*
* @return
* @throws ModbusInitException
*/
public static ModbusMaster getMaster() throws ModbusInitException {
IpParameters params = new IpParameters();
params.setHost("你的硬件ip");
params.setPort("端口号");
//
// modbusFactory.createRtuMaster(wapper); //RTU 协议
// modbusFactory.createUdpMaster(params);//UDP 协议
// modbusFactory.createAsciiMaster(wrapper);//ASCII 协议
ModbusMaster master = modbusFactory.createTcpMaster(params, false);// TCP 协议
master.init();
return master;
}
/**
* 读取[01 Coil Status 0x]类型 开关数据
*
* @param slaveId
* slaveId
* @param offset
* 位置
* @return 读取值
* @throws ModbusTransportException
* 异常
* @throws ErrorResponseException
* 异常
* @throws ModbusInitException
* 异常
*/
public static Boolean readCoilStatus(int slaveId, int offset)
throws ModbusTransportException, ErrorResponseException, ModbusInitException {
// 01 Coil Status
BaseLocator loc = BaseLocator.coilStatus(slaveId, offset);
Boolean value = getMaster().getValue(loc);
return value;
}
/**
* 读取[02 Input Status 1x]类型 开关数据
*
* @param slaveId
* @param offset
* @return
* @throws ModbusTransportException
* @throws ErrorResponseException
* @throws ModbusInitException
*/
public static Boolean readInputStatus(int slaveId, int offset)
throws ModbusTransportException, ErrorResponseException, ModbusInitException {
// 02 Input Status
BaseLocator loc = BaseLocator.inputStatus(slaveId, offset);
Boolean value = getMaster().getValue(loc);
return value;
}
/**
* 读取[03 Holding Register类型 2x]模拟量数据
*
* @param slaveId
* slave Id
* @param offset
* 位置
* @param dataType
* 数据类型,来自com.serotonin.modbus4j.code.DataType
* @return
* @throws ModbusTransportException
* 异常
* @throws ErrorResponseException
* 异常
* @throws ModbusInitException
* 异常
*/
public static Number readHoldingRegister(int slaveId, int offset, int dataType)
throws ModbusTransportException, ErrorResponseException, ModbusInitException {
// 03 Holding Register类型数据读取
BaseLocator loc = BaseLocator.holdingRegister(slaveId, offset, dataType);
Number value = getMaster().getValue(loc);
return value;
}
/**
* 读取[04 Input Registers 3x]类型 模拟量数据
*
* @param slaveId
* slaveId
* @param offset
* 位置
* @param dataType
* 数据类型,来自com.serotonin.modbus4j.code.DataType
* @return 返回结果
* @throws ModbusTransportException
* 异常
* @throws ErrorResponseException
* 异常
* @throws ModbusInitException
* 异常
*/
public static Number readInputRegisters(int slaveId, int offset, int dataType)
throws ModbusTransportException, ErrorResponseException, ModbusInitException {
// 04 Input Registers类型数据读取
BaseLocator loc = BaseLocator.inputRegister(slaveId, offset, dataType);
Number value = getMaster().getValue(loc);
return value;
}
} 2.写入数据
public class Modbus4jWriteUtils {
static Log log = LogFactory.getLog(Modbus4jWriteUtils.class);
/**
* 工厂。
*/
static ModbusFactory modbusFactory;
static {
if (modbusFactory == null) {
modbusFactory = new ModbusFactory();
}
}
/**
* 获取tcpMaster
*
* @return
* @throws ModbusInitException
*/
public static ModbusMaster getMaster() throws ModbusInitException {
IpParameters params = new IpParameters();
params.setHost("你的硬件地址");
params.setPort("端口号");
ModbusMaster tcpMaster = modbusFactory.createTcpMaster(params, false);
tcpMaster.init();
return tcpMaster;
}
/**
* 写 [01 Coil Status(0x)]写一个 function ID = 5
*
* @param slaveId
* slave的ID
* @param writeOffset
* 位置
* @param writeValue
* 值
* @return 是否写入成功
* @throws ModbusTransportException
* @throws ModbusInitException
*/
public static boolean writeCoil(int slaveId, int writeOffset, boolean writeValue)
throws ModbusTransportException, ModbusInitException {
// 获取master
ModbusMaster tcpMaster = getMaster();
// 创建请求
WriteCoilRequest request = new WriteCoilRequest(slaveId, writeOffset, writeValue);
// 发送请求并获取响应对象
WriteCoilResponse response = (WriteCoilResponse) tcpMaster.send(request);
if (response.isException()) {
return false;
} else {
return true;
}
}
/**
* 写[01 Coil Status(0x)] 写多个 function ID = 15
*
* @param slaveId
* slaveId
* @param startOffset
* 开始位置
* @param bdata
* 写入的数据
* @return 是否写入成功
* @throws ModbusTransportException
* @throws ModbusInitException
*/
public static boolean writeCoils(int slaveId, int startOffset, boolean[] bdata)
throws ModbusTransportException, ModbusInitException {
// 获取master
ModbusMaster tcpMaster = getMaster();
// 创建请求
WriteCoilsRequest request = new WriteCoilsRequest(slaveId, startOffset, bdata);
// 发送请求并获取响应对象
WriteCoilsResponse response = (WriteCoilsResponse) tcpMaster.send(request);
if (response.isException()) {
return false;
} else {
return true;
}
}
/***
* 写[03 Holding Register(4x)] 写一个 function ID = 6
*
* @param slaveId
* @param writeOffset
* @param writeValue
* @return
* @throws ModbusTransportException
* @throws ModbusInitException
*/
public static boolean writeRegister(int slaveId, int writeOffset, short writeValue)
throws ModbusTransportException, ModbusInitException {
// 获取master
ModbusMaster tcpMaster = getMaster();
// 创建请求对象
WriteRegisterRequest request = new WriteRegisterRequest(slaveId, writeOffset, writeValue);
WriteRegisterResponse response = (WriteRegisterResponse) tcpMaster.send(request);
if (response.isException()) {
log.error(response.getExceptionMessage());
return false;
} else {
return true;
}
}
/**
*
* 写入[03 Holding Register(4x)]写多个 function ID=16
*
* @param slaveId
* modbus的slaveID
* @param startOffset
* 起始位置偏移量值
* @param sdata
* 写入的数据
* @return 返回是否写入成功
* @throws ModbusTransportException
* @throws ModbusInitException
*/
public static boolean writeRegisters(int slaveId, int startOffset, short[] sdata)
throws ModbusTransportException, ModbusInitException {
// 获取master
ModbusMaster tcpMaster = getMaster();
// 创建请求对象
WriteRegistersRequest request = new WriteRegistersRequest(slaveId, startOffset, sdata);
// 发送请求并获取响应对象
ModbusResponse response = tcpMaster.send(request);
if (response.isException()) {
log.error(response.getExceptionMessage());
return false;
} else {
return true;
}
}
/**
* 写入数字类型的模拟量（如:写入Float类型的模拟量、Double类型模拟量、整数类型Short、Integer、Long）
*
* @param slaveId
* @param offset
* @param value
* 写入值,Number的子类,例如写入Float浮点类型,Double双精度类型,以及整型short,int,long
* @param registerCount
* ,com.serotonin.modbus4j.code.DataType
* @throws ModbusTransportException
* @throws ErrorResponseException
* @throws ModbusInitException
*/
public static void writeHoldingRegister(int slaveId, int offset, Number value, int dataType)
throws ModbusTransportException, ErrorResponseException, ModbusInitException {
// 获取master
ModbusMaster tcpMaster = getMaster();
// 类型
BaseLocator locator = BaseLocator.holdingRegister(slaveId, offset, dataType);
tcpMaster.setValue(locator, value);
}
}