readWriteMultipleRegisters()

Posted by On 02 / 01 / 2019 0 Comment

Description

Sends a packet command to read and write the holding registers of a slave node.

Syntax

node1.readWriteMultipleRegisters(read_address, read_size, write_address, write_size) node2.readWriteMultipleRegisters(read_address, read_size) - Different parameter function and usage. See Example for details.

Parameters

node1/node2: ModbusMasterNode object.

read_address: Starting address of the holding register to read.

read_size: Size of holding register to read.

write_address: Starting address of holding register to write.

write_size: Size of holding register to write.

Return Value

int: Returns MODBUS_SUCCESS on success, EXCEPTION_CODE otherwise.

Example

 

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#include <Arduino.h>

#include <Modbus86.h>

 

ModbusMaster bus1;

ModbusMasterNode node2;

 

uint8_t reg[2];

uint8_t result;

uint32_t receiveData;

 

void setup()

{

    while(!Serial);

    bus1.begin(MODBUS_RTU,Serial1);

    node2.attach(16, bus1);

 

    reg[0] = 0x1234;

    reg[1] = 0xabcd;

    node2.beginTransmission(10);

    node2.send(reg[0]);

    node2.send(reg[1]);

    result = node2.readWriteMultipleRegisters(5, 2);

 

    if (result != MODBUS_SUCCESS) {

        Serial.print("readWriteMultipleRegisters => ErrorCode: ");

        Serial.println(result);

    } else {

        Serial.print("From Holding Register receiveData: ");

        receiveData = node2.getResponseBuffer(0)

                    | (node2.getResponseBuffer(1) << 16);

        Serial.println(receiveData);

    }

}

 

void loop()

{

}

See Also

setTransmitBuffer()
beginTransmission()
send()
getResponseBuffer()

Library Reference

The text of the 86Duino reference is licensed under a Creative Commons Attribution-ShareAlike 3.0 License. Code samples in the reference are released into the public domain.