modbus rtu problem

[defela]

hello aldas, first of all, thank you, but I have a problem, I connected as modbus rtu, but I get the following package error, I make 10-15 queries, it gives as an array, then it is the same again, package parsing error, can you help?

RTU Binary received (in hex): 01030401a100d4aa �����
An exception occurred Packet crc (\xd4aa) does not match calculated crc (\x6caa)! #0 C:\xampp\htdocs\fc4.php(35): ModbusTcpClient\Packet\RtuConverter::fromRtu('\x01\x03\x04\x01\xA1\x00\xD4\xAA') #1 {main}

<?php

use ModbusTcpClient\Network\BinaryStreamConnection;
use ModbusTcpClient\Packet\ModbusFunction\ReadHoldingRegistersRequest;
use ModbusTcpClient\Packet\RtuConverter;
use ModbusTcpClient\Packet\ModbusFunction\ReadHoldingRegistersResponse;

require __DIR__ . '/vendor/autoload.php';
//require __DIR__ . '/logger.php';
$connection = BinaryStreamConnection::getBuilder()
    ->setPort(1001)
    ->setHost('10.20.0.74')
    ->setReadTimeoutSec(3) // increase read timeout to 3 seconds
    ->setIsCompleteCallback(function ($binaryData, $streamIndex) {
        // Do not check for complete TCP packet structure. Default implementation works only for Modbus TCP.
        // Modbus TCP has 7 byte header and this function checks for it and whole packet to be complete. RTU does
        // not have that.
        // Read about differences here: https://www.simplymodbus.ca/TCP.htm
        return true;
    })
   // ->setLogger(new EchoLogger())
    ->build();

$startAddress = 4;
$quantity = 2;
$slaveId = 1; // RTU packet slave id equivalent is Modbus TCP unitId

$tcpPacket = new ReadHoldingRegistersRequest($startAddress, $quantity, $slaveId);
$rtuPacket = RtuConverter::toRtu($tcpPacket);

try {
    $binaryData = $connection->connect()->sendAndReceive($rtuPacket);
    echo 'RTU Binary received (in hex):   ' . unpack('H*', $binaryData)[1] . PHP_EOL;

    $response = RtuConverter::fromRtu($binaryData);
    echo 'Parsed packet (in hex):     ' . $response->toHex() . PHP_EOL;
    echo 'Data parsed from packet (bytes):' . PHP_EOL;
    print_r($response->getData());

} catch (Exception $exception) {
    echo 'An exception occurred' . PHP_EOL;
    echo $exception->getMessage() . PHP_EOL;
    echo $exception->getTraceAsString() . PHP_EOL;
} finally {
    $connection->close();
}

[defela]

<?php

use ModbusTcpClient\Network\BinaryStreamConnection;
use ModbusTcpClient\Packet\ModbusFunction\ReadHoldingRegistersRequest;
use ModbusTcpClient\Packet\RtuConverter;
use ModbusTcpClient\Packet\ModbusFunction\ReadHoldingRegistersResponse;

require __DIR__ . '/vendor/autoload.php';
//require __DIR__ . '/logger.php';
$connection = BinaryStreamConnection::getBuilder()
    ->setPort(1001)
    ->setHost('10.20.0.74')
    ->setReadTimeoutSec(3) // increase read timeout to 3 seconds
    ->setIsCompleteCallback(function ($binaryData, $streamIndex) {
        // Do not check for complete TCP packet structure. Default implementation works only for Modbus TCP.
        // Modbus TCP has 7 byte header and this function checks for it and whole packet to be complete. RTU does
        // not have that.
        // Read about differences here: https://www.simplymodbus.ca/TCP.htm
        return true;
    })
   // ->setLogger(new EchoLogger())
    ->build();

$startAddress = 4;
$quantity = 2;
$slaveId = 1; // RTU packet slave id equivalent is Modbus TCP unitId

$tcpPacket = new ReadHoldingRegistersRequest($startAddress, $quantity, $slaveId);
$rtuPacket = RtuConverter::toRtu($tcpPacket);

try {
    $binaryData = $connection->connect()->sendAndReceive($rtuPacket);
    echo 'RTU Binary received (in hex):   ' . unpack('H*', $binaryData)[1] . PHP_EOL;

    $response = RtuConverter::fromRtu($binaryData);
    echo 'Parsed packet (in hex):     ' . $response->toHex() . PHP_EOL;
    echo 'Data parsed from packet (bytes):' . PHP_EOL;
    print_r($response->getData());

} catch (Exception $exception) {
    echo 'An exception occurred' . PHP_EOL;
    echo $exception->getMessage() . PHP_EOL;
    echo $exception->getTraceAsString() . PHP_EOL;
} finally {
    $connection->close();
}

[defela]

aldas sorry but i couldn't do it this is my code is it possible for you to compile and send it or can you help me if i give anydesk

[defela]

<?php

use ModbusTcpClient\Network\BinaryStreamConnection;
use ModbusTcpClient\Packet\ModbusFunction\ReadHoldingRegistersRequest;
use ModbusTcpClient\Packet\RtuConverter;
use ModbusTcpClient\Packet\ModbusFunction\ReadHoldingRegistersResponse;
use ModbusTcpClient\Packet\ResponseFactory;
use ModbusTcpClient\Packet\ErrorResponse;

require __DIR__ . '/vendor/autoload.php';
//require __DIR__ . '/logger.php';
$connection = BinaryStreamConnection::getBuilder()
    ->setPort(1001)
    ->setHost('10.20.0.74')
    ->setReadTimeoutSec(5) // increase read timeout to 3 seconds
    ->setIsCompleteCallback(function ($binaryData, $streamIndex) {
        // minimal RTU packet length is 5 bytes (1 byte unit id + 1 byte function code + 1 byte of error code or byte length + 2 bytes for CRC)
        $length = strlen($binaryData);
        if ($length < 5) {
            return false;
        }
        if ((ord($binaryData[1]) & ErrorResponse::EXCEPTION_BITMASK) > 0) { // seems to be error response
            return true;
        }
        // if it is not error response then 3rd byte contains data length in bytes

        // leading 3 bytes are = unit id + function code + data length in bytes
        // next is N bytes of data that should match 3rd byte value
        // and 2 bytes for CRC
        // so adding these number is what complete packet would be
        $expectedLength = 3 + ord($binaryData[2]) + 2;

        if ($length > $expectedLength) {
            throw new IOException('packet length more bytes than expected');
        }
        return $length === $expectedLength;
    })
   // ->setLogger(new EchoLogger())
    ->build();

$startAddress = 4;
$quantity = 2;
$slaveId = 1; // RTU packet slave id equivalent is Modbus TCP unitId

$tcpPacket = new ReadHoldingRegistersRequest($startAddress, $quantity, $slaveId);
$rtuPacket = RtuConverter::toRtu($tcpPacket);

try {
    $binaryData = $connection->connect()->sendAndReceive($rtuPacket);
    echo 'RTU Binary received (in hex):   ' . unpack('H*', $binaryData)[1] . PHP_EOL;

    $response = RtuConverter::fromRtu($binaryData);
    echo 'Parsed packet (in hex):     ' . $response->toHex() . PHP_EOL;
    echo 'Data parsed from packet (bytes):' . PHP_EOL;
    print_r($response->getData());

} catch (Exception $exception) {
    echo 'An exception occurred' . PHP_EOL;
    echo $exception->getMessage() . PHP_EOL;
    echo $exception->getTraceAsString() . PHP_EOL;
} finally {
    $connection->close();
}

[defela]

anydesk id : 337104046

[defela]

I would be very happy

[aldas]

Hi, I have release new version 3.1.0 with some RTU related improvements. And added new example with RTU over TCP https:/aldas/modbus-tcp-client/blob/master/examples/rtu_over_tcp_with_higherlevel_api.php which should work. At least when I tested with https://www.modbusdriver.com/diagslave.html it worked

[defela]

aldas thanks a lot i read it but do you have any idea about this problem multiple connections at the same time

[defela]

thank you very much

[defela]

aldas hello unfortunately, modbus rtu creates problems in more than one query, can we read from serial ports on windows machine instead? serial ports are connected to windows machine as com1 com2

[defela]

`<?php

use ModbusTcpClient\Packet\ModbusFunction\ReadInputRegistersRequest;
use ModbusTcpClient\Packet\ModbusFunction\ReadInputRegistersResponse;
use ModbusTcpClient\Packet\RtuConverter;

require DIR . '/../vendor/autoload.php';

if (stripos(PHP_OS, 'WIN') === 0) {
echo 'This example can not be run in Windows!' . PHP_EOL;
exit(0);
}

$startAddress = 1;
$quantity = 2;
$slaveId = 1; // RTU packet slave id equivalent is Modbus TCP unitId

$tcpPacket = new ReadInputRegistersRequest($startAddress, $quantity, $slaveId);
$rtuPacket = RtuConverter::toRtu($tcpPacket);

try {
$device = '/dev/ttyUSB0';
$fd = fopen($device, 'w+b');

$sttyModes = implode(' ', [
    'cs8', // enable character size 8 bits
    '9600', // enable baud rate 9600
    '-icanon', // disable enable special characters: erase, kill, werase, rprnt
    'min 0', // with -icanon, set N characters minimum for a completed read
    'ignbrk', // enable ignore break characters
    '-brkint', // disable breaks cause an interrupt signal
    '-icrnl', // disable translate carriage return to newline
    '-imaxbel', // disable beep and do not flush a full input buffer on a character
    '-opost', // disable postprocess output
    '-onlcr', // disable translate newline to carriage return-newline
    '-isig', // disable interrupt, quit, and suspend special characters
    '-iexten', // disable non-POSIX special characters
    '-echo', // disable echo input characters
    '-echoe', // disable echo erase characters as backspace-space-backspace
    '-echok', // disable echo a newline after a kill character
    '-echoctl', // disable same as [-]ctlecho
    '-echoke', // disable kill all line by obeying the echoprt and echoe settings
    '-noflsh', // disable flushing after interrupt and quit special characters
    '-ixon', // disable XON/XOFF flow control
    '-crtscts', // disable RTS/CTS handshaking
]);
$sttyResult = exec("stty -F ${device} ${sttyModes}");
if ($sttyResult === false) {
    echo 'stty command failed' . PHP_EOL;
    exit(1);
}

echo 'RTU Binary to sent (in hex):   ' . unpack('H*', $rtuPacket)[1] . PHP_EOL;
fwrite($fd, $rtuPacket);
fflush($fd);

$binaryData = '';
$start = microtime(true);

do {
    // give sensor (5ms) some time to respond. SHT20 modbus minimal response time seems to be 20ms and more
    usleep(5000);
    $binaryData = fread($fd, 255);
} while ($binaryData === '');

$end = (microtime(true) - $start) * 1000;
echo 'Response in: ' . $end . ' ms' . PHP_EOL;

echo 'RTU Binary received (in hex):   ' . unpack('H*', $binaryData)[1] . PHP_EOL;

/** @var ReadInputRegistersResponse $response */
$response = RtuConverter::fromRtu($binaryData)->withStartAddress($startAddress);
echo 'Parsed packet (in hex):     ' . $response->toHex() . PHP_EOL;

echo PHP_EOL;
echo 'Temperature: ' . ($response->getWordAt(1)->getInt16() / 10) . PHP_EOL;
echo 'Humidity: ' . ($response->getWordAt(2)->getInt16() / 10) . PHP_EOL;

} catch (Exception $exception) {
echo 'An exception occurred' . PHP_EOL;
echo $exception->getMessage() . PHP_EOL;
echo $exception->getTraceAsString() . PHP_EOL;
} finally {
fclose($fd);
}`

[defela]

Here you said that if it is not a windows machine, how should I connect to the coms of the windows machine?

[aldas]

Maybe https://stackoverflow.com/a/1074273/2514290 ? I really no not know as I use Windows only for gaming and these days it is quite rare occasion.

$output = exec("mode COM2: BAUD=115200 PARITY=N data=8 stop=1 XON=off TO=on dtr=off odsr=off octs=off rts=on idsr=off");
$fp = fopen("COM2", "r+");