readHoldingRegisters()

Posted by On 02 / 01 / 2019 0 Comment

Description

Sends a packet command to the Slave node to read the Holding Registers register.

Syntax

node1.readHoldingRegisters(read_address, read_size)

Parameters

node1: ModbusMasterNode object.

read_address: The starting address of the Holding Registers register to be read.

read_size: The size of the Holding Registers register to be read.

Return

int: If successful, return MODBUS_SUCCESS, otherwise return EXCEPTION_CODE .

Example

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#include <Modbus86.h>

  

ModbusMaster bus1;

ModbusMasterNode node1;

 

uint8_t result;

uint32_t receiveData;

 

void setup()

{

    while(!Serial);

    Serial1.begin(115200);

    bus1.begin(MODBUS_RTU, Serial1);

    node1.attach(16, bus1);

     

    result = node1.readHoldingRegisters(5, 2);

     

    if (result != MODBUS_SUCCESS) {

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

        Serial.println(result);

    } else {

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

        receiveData = node1.getResponseBuffer(0)

                 | (node1.getResponseBuffer(1) << 16);

 

        Serial.println(receiveData);

    }

}

  

void loop()

{

}

 

See Also

－ getResponseBuffer()

Library Reference

The text in the 86Duino reference is modified from the Arduino reference and is licensed under the Creative Commons Attribution-Share Alike 3.0 License  . The code examples in the reference have been released into the public domain.