We Keep Coding

EasyModBus modbusClient.ReadHoldingRegisters() returning unexpected 0

Background:
We have been using the Schneider M251 PLC with the TM3AI8, TM3DQ8R and TM3DI8 modules for some time now and I have noticed that we are getting unexpected values being sent over Modbus tcp.
Most of the time, the signal we receive over the Modbus protocol is in the 4mA range at the lower portion of our expected signal. However, we are seeing an intermittent 0 that is infrequently sent to our java software over modbus tcp using the easy modbus tcp library
Library: http://easymodbustcp.net/en/
Specifically, when we call:
val = modbusClient.ReadHoldingRegisters(3005, 1)[0];
We are seeing an intermittent infrequent val = 0 appearing but only infrequently. When I check the PLC software called soMachine, it does not appear to ever show a zero value. Has anyone encountered this kind of issue before? I set up a POU using structure text to count the number of times the IO reading is 0 and apparently it never is. So I think it has something to do with the modbus library.
I have provided a system.out.println(val) below showing the issue:
VAL IS THIS NOW: 3995
VAL IS THIS NOW: 3989
VAL IS THIS NOW: 3995
VAL IS THIS NOW: 3995
VAL IS THIS NOW: 3986
VAL IS THIS NOW: 3998
VAL IS THIS NOW: 3992
VAL IS THIS NOW: 3989
VAL IS THIS NOW: 3998
VAL IS THIS NOW: 3995
VAL IS THIS NOW: 0 <- Random intermittent 0
VAL IS THIS NOW: 3986
VAL IS THIS NOW: 3998
VAL IS THIS NOW: 3992
VAL IS THIS NOW: 3989
VAL IS THIS NOW: 3995
VAL IS THIS NOW: 3989
VAL IS THIS NOW: 3989
The I/O config on the plc is 0-20mA extended and the sensor is A 4-20mA sensor. A zero reading on our unit scale represents -2500units which poses an issue for our system given it represents a large discrepancy in our measurement. We are using the diagnostic bits which are available on the Schneider card as well as well to detect sensor faults. However, the sensor does not appear to be faulty and is working fine.
As you can see, the signal off the IO card is a bit noisy as well. A multimeter does not fluctuate when reading the voltage for this sensor and it is really stable on our multimeters at the 3.989mV range.
When we see the intermittent 0's printed to the console, we do not see the 0's in soMachine. Further, the method polling for the values is being called every 250ms.
We have resorted to the following "filter" but it is not an ideal solution to the issue.
static int pt05ErrorCount = 0, pt05lastVal;
private static double readRegister3005() throws IOException{
try {
int val;
if(PLC.isConnected()) {
val = modbusClient.ReadHoldingRegisters(3005, 1)[0];
if(val > 0) {
pt05ErrorCount = 0;
pt05lastVal = val;
}
}else {
val = -1000;
}
System.out.println("VAL IS THIS NOW: "+val);
if(val > 0) {
return (double) (10000-0)/(20-4)*((double) val/1000-4)+0; //convert mA to psig
}else {
if(pt05ErrorCount > maxErrorCount) {
pt05ErrorCount++;
return (double) (10000-0)/(20-4)*((double) val/1000-4)+0;
}else {
return (double) (10000-0)/(20-4)*((double) pt05lastVal/1000-4)+0;
}
}
} catch(Exception e) {
System.out.println(e);
throw new IOException(Globals.getSystemCalendarDateandTime() + " PLC.java > readRegister3005(): ERROR reading PLC address 3005.");
}
}
Please let me know if you require more information about the issue.
The ReadHoldingRegisters method is as follows:
/**
* Read Holding Registers from Server
* #param startingAddress Fist Address to read; Shifted by -1
* #param quantity Number of Inputs to read
* #return Holding Registers from Server
* #throws de.re.easymodbus.exceptions.ModbusException
* #throws UnknownHostException
* #throws SocketException
* #throws SerialPortTimeoutException
* #throws SerialPortException
*/
public int[] ReadHoldingRegisters(int startingAddress, int quantity) throws de.re.easymodbus.exceptions.ModbusException,
UnknownHostException, SocketException, IOException, SerialPortException, SerialPortTimeoutException
{
if (tcpClientSocket == null)
throw new de.re.easymodbus.exceptions.ConnectionException("connection Error");
if (startingAddress > 65535 | quantity > 125)
throw new IllegalArgumentException("Starting adress must be 0 - 65535; quantity must be 0 - 125");
int[] response = new int[quantity];
this.transactionIdentifier = toByteArray(0x0001);
this.protocolIdentifier = toByteArray(0x0000);
this.length = toByteArray(0x0006);
//serialdata = this.unitIdentifier;
this.functionCode = 0x03;
this.startingAddress = toByteArray(startingAddress);
this.quantity = toByteArray(quantity);
byte[] data = new byte[]
{
this.transactionIdentifier[1],
this.transactionIdentifier[0],
this.protocolIdentifier[1],
this.protocolIdentifier[0],
this.length[1],
this.length[0],
this.unitIdentifier,
this.functionCode,
this.startingAddress[1],
this.startingAddress[0],
this.quantity[1],
this.quantity[0],
this.crc[0],
this.crc[1]
};
if (this.serialflag)
{
crc = calculateCRC(data, 6, 6);
data[data.length -2] = crc[0];
data[data.length -1] = crc[1];
}
byte[] serialdata = null;
if (serialflag)
{
serialdata = new byte[8];
java.lang.System.arraycopy(data, 6,serialdata,0,8);
serialPort.purgePort(SerialPort.PURGE_RXCLEAR);
serialPort.writeBytes(serialdata);
if (debug) StoreLogData.getInstance().Store("Send Serial-Data: "+ Arrays.toString(serialdata));
long dateTimeSend = DateTime.getDateTimeTicks();
byte receivedUnitIdentifier = (byte)0xFF;
serialdata = new byte[256];
int expectedlength = 5+2*quantity;
while (receivedUnitIdentifier != this.unitIdentifier & !((DateTime.getDateTimeTicks() - dateTimeSend) > 10000 * this.connectTimeout))
{
serialdata = serialPort.readBytes(expectedlength, this.connectTimeout);
receivedUnitIdentifier = serialdata[0];
}
if (receivedUnitIdentifier != this.unitIdentifier)
{
data = new byte[256];
}
if (serialdata != null)
{
data = new byte[262];
System.arraycopy(serialdata, 0, data, 6, serialdata.length);
if (debug) StoreLogData.getInstance().Store("Receive ModbusRTU-Data: " + Arrays.toString(data));
}
for (int i = 0; i < quantity; i++)
{
byte[] bytes = new byte[2];
bytes[0] = data[3+i*2];
bytes[1] = data[3+i*2+1];
ByteBuffer byteBuffer = ByteBuffer.wrap(bytes);
response[i] = byteBuffer.getShort();
}
}
if (tcpClientSocket.isConnected() | udpFlag)
{
if (udpFlag)
{
InetAddress ipAddress = InetAddress.getByName(this.ipAddress);
DatagramPacket sendPacket = new DatagramPacket(data, data.length, ipAddress, this.port);
DatagramSocket clientSocket = new DatagramSocket();
clientSocket.setSoTimeout(500);
clientSocket.send(sendPacket);
data = new byte[2100];
DatagramPacket receivePacket = new DatagramPacket(data, data.length);
clientSocket.receive(receivePacket);
clientSocket.close();
data = receivePacket.getData();
}
else
{
outStream.write(data, 0, data.length-2);
if (debug) StoreLogData.getInstance().Store("Send ModbusTCP-Data: "+Arrays.toString(data));
if (sendDataChangedListener.size() > 0)
{
sendData = new byte[data.length-2];
System.arraycopy(data, 0, sendData, 0, data.length-2);
for (SendDataChangedListener hl : sendDataChangedListener)
hl.SendDataChanged();
}
data = new byte[2100];
int numberOfBytes = inStream.read(data, 0, data.length);
if (receiveDataChangedListener.size() > 0)
{
receiveData = new byte[numberOfBytes];
System.arraycopy(data, 0, receiveData, 0, numberOfBytes);
for (ReceiveDataChangedListener hl : receiveDataChangedListener)
hl.ReceiveDataChanged();
if (debug) StoreLogData.getInstance().Store("Receive ModbusTCP-Data: " + Arrays.toString(data));
}
}
}
if (((int) data[7]) == 0x83 & ((int) data[8]) == 0x01)
{
if (debug) StoreLogData.getInstance().Store("FunctionCodeNotSupportedException Throwed");
throw new de.re.easymodbus.exceptions.FunctionCodeNotSupportedException("Function code not supported by master");
}
if (((int) data[7]) == 0x83 & ((int) data[8]) == 0x02)
{
if (debug) StoreLogData.getInstance().Store("Starting adress invalid or starting adress + quantity invalid");
throw new de.re.easymodbus.exceptions.StartingAddressInvalidException("Starting adress invalid or starting adress + quantity invalid");
}
if (((int) data[7]) == 0x83 & ((int) data[8]) == 0x03)
{
if (debug) StoreLogData.getInstance().Store("Quantity invalid");
throw new de.re.easymodbus.exceptions.QuantityInvalidException("Quantity invalid");
}
if (((int) data[7]) == 0x83 & ((int) data[8]) == 0x04)
{
if (debug) StoreLogData.getInstance().Store("Error reading");
throw new de.re.easymodbus.exceptions.ModbusException("Error reading");
}
for (int i = 0; i < quantity; i++)
{
byte[] bytes = new byte[2];
bytes[0] = data[9+i*2];
bytes[1] = data[9+i*2+1];
ByteBuffer byteBuffer = ByteBuffer.wrap(bytes);
response[i] = byteBuffer.getShort();
}
return (response);
}
Regards,

Microsoft Asynchronous Conversation Transcription problem: SLF4J problem + Connection Issue Error 11001

I tried to run the sample code from:
https://learn.microsoft.com/en-us/azure/cognitive-services/speech-service/how-to-async-conversation-transcription
implementing helper class from:
https://github.com/Azure-Samples/cognitive-services-speech-sdk/blob/master/samples/java/jre/console/src/com/microsoft/cognitiveservices/speech/samples/console/WavStream.java
with some slight modifications so that it can read in wav files not limited to 16kHz 16bit single channel, and when I run it, this comes up:
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Conversation transcriber canceled:SessionId:b2496d2c13424b3ba3138f2c8ce0893f ResultId:258796dbc69d491786f3ccdd8ec708d6 CancellationReason:Error CancellationErrorCode:ConnectionFailure Error details:<Connection failed (no connection to the remote host). Internal error: 1. Error details: 11001. Please check network connection, firewall setting, and the region name used to create speech factory. SessionId: b2496d2c13424b3ba3138f2c8ce0893f
Conversation transcriber stopped:SessionId: b2496d2c13424b3ba3138f2c8ce0893f.
I'm pretty sure that the API key and the region setup are correct and running and the Internet configuration isn't having any problem.
Here are the codes:
Main.java:
package speechsdk.quickstart;
import com.azure.core.util.polling.PollerFlux;
import com.azure.core.util.polling.SyncPoller;
import com.microsoft.cognitiveservices.speech.*;
import com.microsoft.cognitiveservices.speech.audio.*;
import com.microsoft.cognitiveservices.speech.remoteconversation.RemoteConversationTranscriptionClient;
import com.microsoft.cognitiveservices.speech.remoteconversation.RemoteConversationTranscriptionOperation;
import com.microsoft.cognitiveservices.speech.remoteconversation.RemoteConversationTranscriptionResult;
import com.microsoft.cognitiveservices.speech.transcription.Conversation;
import com.microsoft.cognitiveservices.speech.transcription.ConversationTranscriber;
import com.microsoft.cognitiveservices.speech.transcription.ConversationTranscriptionResult;
import javax.sound.sampled.AudioFileFormat;
import java.io.FileInputStream;
import java.util.UUID;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
/**
* Quickstart: recognize speech using the Speech SDK for Java.
*/
public class Main {
/**
* #param args Arguments are ignored in this sample.
*/
public static void main(String[] args) {
try {
// Create the speech config object
SpeechConfig speechConfig = SpeechConfig.fromSubscription("APIKEY", "SERVICEREGION");
speechConfig.setProperty("ConversationTranscriptionInRoomAndOnline", "true");
// Set the property for asynchronous transcription
speechConfig.setServiceProperty("transcriptionMode", "Async", ServicePropertyChannel.UriQueryParameter);
// Set the property for real-time plus asynchronous transcription
//speechConfig.setServiceProperty("transcriptionMode", "RealTimeAndAsync", ServicePropertyChannel.UriQueryParameter);
// pick a conversation Id that is a GUID.
String conversationId = UUID.randomUUID().toString();
// Create a Conversation
Conversation conversation = new Conversation(speechConfig, conversationId);
// Create an audio stream from a wav file or from the default microphone if you want to stream live audio from the supported devices
// Replace with your own audio file name and Helper class which implements AudioConfig using PullAudioInputStreamCallback
WavStream wavStream = new WavStream(new FileInputStream("sample.wav"));
PullAudioInputStreamCallback wavfilePullStreamCallback = wavStream;
// Create an audio stream format assuming the file used above is 16Khz, 16 bits and 8 channel pcm wav file
//AudioStreamFormat audioStreamFormat = AudioStreamFormat.getWaveFormatPCM((long)16000, (short)16,(short)8);
AudioStreamFormat audioStreamFormat = AudioStreamFormat.getWaveFormatPCM(wavStream.getSamplespersecond(), (short) wavStream.getBitspersample(), (short) wavStream.getChannel());
// Create an input stream
AudioInputStream audioStream = AudioInputStream.createPullStream(wavfilePullStreamCallback, audioStreamFormat);
// Create a conversation transcriber
ConversationTranscriber transcriber = new ConversationTranscriber(AudioConfig.fromStreamInput(audioStream));
// join a conversation
transcriber.joinConversationAsync(conversation);
// Add the event listener for the realtime events
transcriber.transcribed.addEventListener((o, e) -> {
System.out.println("Conversation transcriber Recognized:" + e.toString());
});
transcriber.canceled.addEventListener((o, e) -> {
System.out.println("Conversation transcriber canceled:" + e.toString());
try {
transcriber.stopTranscribingAsync().get();
} catch (InterruptedException ex) {
ex.printStackTrace();
} catch (ExecutionException ex) {
ex.printStackTrace();
}
});
transcriber.sessionStopped.addEventListener((o, e) -> {
System.out.println("Conversation transcriber stopped:" + e.toString());
try {
transcriber.stopTranscribingAsync().get();
} catch (InterruptedException ex) {
ex.printStackTrace();
} catch (ExecutionException ex) {
ex.printStackTrace();
}
});
// start the transcription.
Future<?> future = transcriber.startTranscribingAsync();
// Create a remote Conversation Transcription client
RemoteConversationTranscriptionClient client = new RemoteConversationTranscriptionClient(speechConfig);
// Get the PollerFlux for the remote operation
PollerFlux<RemoteConversationTranscriptionOperation, RemoteConversationTranscriptionResult> remoteTranscriptionOperation = client.getTranscriptionOperation(conversationId);
// Subscribe to PollerFlux to get the remote operation status
remoteTranscriptionOperation.subscribe(
pollResponse -> {
System.out.println("Poll response status : " + pollResponse.getStatus());
System.out.println("Poll response status : " + pollResponse.getValue().getServiceStatus());
}
);
// Obtain the blocking operation using getSyncPoller
SyncPoller<RemoteConversationTranscriptionOperation, RemoteConversationTranscriptionResult> blockingOperation = remoteTranscriptionOperation.getSyncPoller();
// Wait for the operation to finish
blockingOperation.waitForCompletion();
// Get the final result response
RemoteConversationTranscriptionResult resultResponse = blockingOperation.getFinalResult();
// Print the result
if(resultResponse != null) {
if(resultResponse.getConversationTranscriptionResults() != null) {
for (int i = 0; i < resultResponse.getConversationTranscriptionResults().size(); i++) {
ConversationTranscriptionResult result = resultResponse.getConversationTranscriptionResults().get(i);
System.out.println(result.getProperties().getProperty(PropertyId.SpeechServiceResponse_JsonResult.name()));
System.out.println(result.getProperties().getProperty(PropertyId.SpeechServiceResponse_JsonResult));
System.out.println(result.getOffset());
System.out.println(result.getDuration());
System.out.println(result.getUserId());
System.out.println(result.getReason());
System.out.println(result.getResultId());
System.out.println(result.getText());
System.out.println(result.toString());
}
}
}
System.out.println("Operation finished");
} catch (Exception ex) {
//System.out.println("Unexpected exception: " + ex.getMessage());
ex.printStackTrace();
assert(false);
System.exit(1);
}
}
}
Helper.java:
package speechsdk.quickstart;
import com.microsoft.cognitiveservices.speech.audio.PullAudioInputStreamCallback;
import com.microsoft.cognitiveservices.speech.internal.AudioConfig;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import org.slf4j.*;
class WavStream extends PullAudioInputStreamCallback {
private final InputStream stream;
private long samplespersecond;
private int bitspersample;
private int channel;
public long getSamplespersecond()
{
return samplespersecond;
}
public int getBitspersample()
{
return bitspersample;
}
public int getChannel()
{
return channel;
}
public WavStream(InputStream wavStream) {
try {
this.stream = parseWavHeader(wavStream);
} catch (Exception ex) {
throw new IllegalArgumentException(ex.getMessage());
}
}
#Override
public int read(byte[] dataBuffer) {
long ret = 0;
try {
ret = this.stream.read(dataBuffer, 0, dataBuffer.length);
} catch (Exception ex) {
System.out.println("Read " + ex);
}
return (int)Math.max(0, ret);
}
#Override
public void close() {
try {
this.stream.close();
} catch (IOException ex) {
// ignored
}
}
// endregion
// region Wav File helper functions
private int ReadInt32(InputStream inputStream) throws IOException {
int n = 0;
for (int i = 0; i < 4; i++) {
n |= inputStream.read() << (i * 8);
}
return n;
}
private long ReadUInt32(InputStream inputStream) throws IOException {
long n = 0;
for (int i = 0; i < 4; i++) {
n |= inputStream.read() << (i * 8);
}
return n;
}
private int ReadUInt16(InputStream inputStream) throws IOException {
int n = 0;
for (int i = 0; i < 2; i++) {
n |= inputStream.read() << (i * 8);
}
return n;
}
public InputStream parseWavHeader(InputStream reader) throws IOException {
// Note: assumption about order of chunks
// Tag "RIFF"
byte data[] = new byte[4];
int numRead = reader.read(data, 0, 4);
ThrowIfFalse((numRead == 4) && (data[0] == 'R') && (data[1] == 'I') && (data[2] == 'F') && (data[3] == 'F'), "RIFF");
// Chunk size
/* int fileLength = */ReadInt32(reader);
// Subchunk, Wave Header
// Subchunk, Format
// Tag: "WAVE"
numRead = reader.read(data, 0, 4);
ThrowIfFalse((numRead == 4) && (data[0] == 'W') && (data[1] == 'A') && (data[2] == 'V') && (data[3] == 'E'), "WAVE");
// Tag: "fmt"
numRead = reader.read(data, 0, 4);
ThrowIfFalse((numRead == 4) && (data[0] == 'f') && (data[1] == 'm') && (data[2] == 't') && (data[3] == ' '), "fmt ");
// chunk format size
long formatSize = ReadInt32(reader);
ThrowIfFalse(formatSize >= 16, "formatSize");
int formatTag = ReadUInt16(reader);
int channels = ReadUInt16(reader);
int samplesPerSec = (int) ReadUInt32(reader);
int avgBytesPerSec = (int) ReadUInt32(reader);
int blockAlign = ReadUInt16(reader);
int bitsPerSample = ReadUInt16(reader);
ThrowIfFalse(formatTag == 1, "PCM"); // PCM
//ThrowIfFalse(channels == 1, "single channel");
channel = channels;
//ThrowIfFalse(samplesPerSec == 16000, "samples per second");
samplespersecond = samplesPerSec;
//ThrowIfFalse(bitsPerSample == 16, "bits per sample");
bitspersample = bitsPerSample;
// Until now we have read 16 bytes in format, the rest is cbSize and is ignored
// for now.
if (formatSize > 16) {
numRead = reader.read(new byte[(int) (formatSize - 16)]);
ThrowIfFalse(numRead == (int)(formatSize - 16), "could not skip extended format");
}
// Second Chunk, data
// tag: data.
numRead = reader.read(data, 0, 4);
//for (byte i : data) System.out.print((char) i);
//System.out.println();
//ThrowIfFalse((numRead == 4) && (data[0] == 'd') && (data[1] == 'a') && (data[2] == 't') && (data[3] == 'a'), "data");
// data chunk size
// Note: assumption is that only a single data chunk
/* int dataLength = */ReadInt32(reader);
numRead = reader.read(data, 0, 4);
while (!((numRead == 4) && (data[0] == 'd') && (data[1] == 'a') && (data[2] == 't') && (data[3] == 'a')))
{
numRead = reader.read(data, 0, 4);
//for (byte i : data) System.out.print((char) i);
//System.out.println();
ReadInt32(reader);
}
//for (byte i : data) System.out.println((char) i);
return reader;
}
private static void ThrowIfFalse(Boolean condition, String message) {
if (!condition) {
throw new IllegalArgumentException(message);
}
}
// endregion
}

Using azure document, if you can please configure the following and provide us the log.
config.setProperty(PropertyId.Speech_LogFilename, "LogfilePathAndName");
By the way, what is the region you are using to do the transcription?

For conversation transcription, the input wave file should be 8 channel, 16 bits and 16 Khz wave file. Try putting a sleep after the following code till you get the session stopped called.
// start the transcription.
Future<?> future = transcriber.startTranscribingAsync();
Also if possible change the following code to
PollerFlux<RemoteConversationTranscriptionOperation, RemoteConversationTranscriptionResult> remoteTranscriptionOperation = client.getTranscriptionOperation(conversationId,5);
Do let us know if it works.

Read and Write to USB Device on Raspberry Pi 3 using Java

I'm using Raspbian on a Raspberry Pi 3. I'm learning how to code in Java (SE runtime version 1.8.0_65), and I need to communicate raw data with a USB connected Bill Acceptor. According to the manufacturer's documentation, the USB unit mimics a serial-type interface. When I plug the device in, it appears in /dev/serial/by-id. I wrote C code 20+ years ago using modems on SCO Unix setups. If memory serves, I basically treated the modems /dev/ttyxx as a file for reading and writing. I wrote a C++ program 10+ years ago on Windows XP using a similar Bill Acceptor unit (same manufacturer and model) connected to a serial port instead of USB. The documentation shows both USB and serial units use the same data strings for input and output, so I know the SendString data should be correct for triggering a valid response. However, I'm not getting a reply from the unit, so I'm guessing I'm not connecting properly to it.
Here is the code...
public static void main(String[] args) {
try
{
System.out.println("*****************************");
System.out.println("***** Starting Program *****");
System.out.println("*****************************");
String strUsbDeviceDir = "/dev/serial/by-id";
File myUsbDeviceDir = new File(strUsbDeviceDir);
if(myUsbDeviceDir.exists())
{
String[] myUsbDevices = myUsbDeviceDir.list();
for(int i=0; i<myUsbDevices.length; i++)
{
if(myUsbDevices[i].contains("EBDS_over_USB"))
{
System.out.println("Connecting to " + myUsbDevices[i]);
funcBillAcceptor(strUsbDeviceDir + "/" + myUsbDevices[i]);
}
else
{
System.out.println("Not using " + myUsbDevices[i]);
}
}
}
}
catch (Exception ex)
{
System.err.println(ex.toString());
}
}
public static void funcBillAcceptor(String strBillAcceptor)
{
boolean bOddCount = false;
byte[] SendString = new byte[8];
byte[] RecvString = new byte[10];
byte CheckDigit;
int iSendStringCount, iRecvStringCount, iRecvEmptyCount;
try
{
File fBillAcceptor = new File(strBillAcceptor);
if(!fBillAcceptor.canRead())
{
System.out.println("No Read Permission for " + strBillAcceptor);
return;
}
if(!fBillAcceptor.canWrite())
{
System.out.println("No Write Permission for " + strBillAcceptor);
return;
}
RandomAccessFile rafBillAcceptor = new RandomAccessFile(strBillAcceptor, "rwd");
if(rafBillAcceptor != null)
{
System.out.println("Successfully opened " + strBillAcceptor);
}
while(fBillAcceptor.exists())
{
SendString[0] = (byte) 0x02; //STX
SendString[1] = (byte) 0x08;
if(bOddCount)
{
SendString[2] = (byte) 0x10;
bOddCount = false;
}
else
{
SendString[2] = (byte) 0x11;
bOddCount = true;
}
SendString[3] = (byte) 0x1F;
SendString[4] = (byte) 0x0C;
SendString[5] = (byte) 0x00;
SendString[6] = (byte) 0x03; //ETX
//CheckDigit skips STX (byte 0) with byte 1 as seed/initial value
//To calculate the check digit, start with next byte (2)
CheckDigit = SendString[1];
iSendStringCount = 2;
while(SendString[iSendStringCount] != 0x03)
{
CheckDigit = (byte) (SendString[iSendStringCount]^CheckDigit); //XOR current CheckDigit value with next byte
iSendStringCount++;
}
iSendStringCount++; //advance one more so we don't overwrite ETX
SendString[iSendStringCount] = (byte) CheckDigit;
try
{
rafBillAcceptor.write(SendString);
System.out.println("Sent: " + DatatypeConverter.printHexBinary(SendString));
}
catch (Exception ex)
{
System.err.println("Write exception: " + ex.toString());
}
System.out.println("Reading...");
iRecvStringCount = iRecvEmptyCount = 0;
try
{
do
{
iRecvStringCount = rafBillAcceptor.read(RecvString);
System.out.println("Read " + iRecvStringCount + " bytes.");
if(iRecvStringCount < 0)
{
iRecvEmptyCount++;
Thread.sleep(5);
}
} while (iRecvStringCount < 0 && iRecvEmptyCount < 100);
if(iRecvStringCount > 0)
{
System.out.println("Received: " + DatatypeConverter.printHexBinary(RecvString));
}
}
catch (Exception ex)
{
System.err.println("Read exception: " + ex.toString());
}
}
}
catch (Exception ex)
{
System.err.println(ex.toString());
}
}
Here is the output I'm getting...
*****************************
***** Starting Program *****
*****************************
Connecting to usb-Silicon_Labs_Series_2000_Bill_Acceptor__EBDS_over_USB__46580120748-if00-port0
Successfully opened /dev/serial/by-id/usb-Silicon_Labs_Series_2000_Bill_Acceptor__EBDS_over_USB__46580120748-if00-port0
Sent: 0208111F0C00030A
Reading...
Am I missing something obvious, or just going about this all wrong? Thanks for any suggestions!

I was able to successfully communicate with the Bill Acceptor from a Raspberry Pi 3 (running Raspbian) using the RXTXComm library. When communicating with the device from an old Windows XP computer using a 9-pin serial/RS232 harness, I had to use 9600/7/E/1. If I don't use those values for setSerialPortParams (in my sample code), I'm not able to correctly send/receive data. So, you need to know what the device is expecting in order to use this approach with other "serial" hardware connected via USB. Below is code with the basic functionality. I started with one of the sample programs that come with the RXTXComm library and built out from there. Since this is a sample program, I haven't yet added logic to verify the checksum digit for data coming from the device.
You may notice at the bottom of the code that I'm able to determine the /dev/ttyUSBx using the canonical name of the device that I pull from the /dev/serial/by-id directory/folder. It finds the correct device name regardless of which USB port the unit is plugged in to or what order the USB devices get initialized by the system. I have a card dispenser that is also a USB serial device, so I was able to test and confirm this functionality.
public TwoWaySerialComm()
{
super();
}
static boolean bReadyToSend = false;
void connect ( String portName ) throws Exception
{
CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName);
if ( portIdentifier.isCurrentlyOwned() )
{
System.out.println("Error: " + portName + " is currently in use.");
}
else
{
CommPort commPort = portIdentifier.open(this.getClass().getName(), 2000);
if ( commPort instanceof SerialPort )
{
SerialPort serialPort = (SerialPort) commPort;
serialPort.setSerialPortParams(9600, SerialPort.DATABITS_7, SerialPort.STOPBITS_1, SerialPort.PARITY_EVEN);
InputStream in = serialPort.getInputStream();
OutputStream out = serialPort.getOutputStream();
// Thread handling logic
// https://www.javaspecialists.eu/archive/Issue056.html
Thread readThread = new Thread(new SerialReader(in));
readThread.start();
Thread writeThread = new Thread(new SerialWriter(out));
writeThread.start();
// Running threads for 10 seconds then stopping to ensure threads are shutting down
long threadCurrTime = System.currentTimeMillis();
long threadStartTime = System.currentTimeMillis();
while( (threadCurrTime - threadStartTime) < 10000)
{
try
{
Thread.sleep(100);
}
catch (InterruptedException ex)
{
Logger.getLogger(TwoWaySerialComm.class.getName()).log(Level.SEVERE, null, ex);
}
threadCurrTime = System.currentTimeMillis();
}
if(writeThread.isAlive())
{
//System.out.println("Sending interrupt to SerialWriter thread...");
writeThread.interrupt();
writeThread.join();
//System.out.println("SerialWriter thread is shut down.");
}
//else
//{
// System.out.println("SerialWriter thread is already shut down.");
//}
if(readThread.isAlive())
{
//System.out.println("Sending interrupt to SerialReader thread...");
readThread.interrupt();
readThread.join();
//System.out.println("SerialReader thread is shut down.");
}
//else
//{
// System.out.println("SerialReader thread is already shut down.");
//}
commPort.close();
}
else
{
System.out.println("Error: " + portName + " is not recognized as a valid serial device.");
}
}
}
/* SerialReader thread logic */
public static class SerialReader implements Runnable
{
InputStream in;
boolean bShuttingDown = false;
public SerialReader ( InputStream in )
{
this.in = in;
}
public void run ()
{
byte[] RecvString = new byte[12];
String strResponse;
int len = -1;
try
{
while (!bShuttingDown)
{
len = this.in.read(RecvString);
if( len > -1 )
{
strResponse = "";
if(RecvString[0] == 0x02 && RecvString[9] == 0x03)
{
if(RecvString[3] == 0x00 && RecvString[4] == 0x00 && RecvString[5] == 0x00 && RecvString[6] == 0x00)
{
strResponse = "Device not ready.";
}
else
{
//-- RecvString[3]------------------
if(RecvString[3] == 0x01)
strResponse = " - Idling";
else
if(RecvString[3] == 0x02)
strResponse = " - Accepting";
else
if(RecvString[3] == 0x04)
{
strResponse = " - Escrowed";
if(RecvString[5] == 0x08)
strResponse += " $1";
else
if(RecvString[5] == 0x10)
strResponse += " $2";
else
if(RecvString[5] == 0x18)
strResponse += " $5";
else
if(RecvString[5] == 0x20)
strResponse += " $10";
else
if(RecvString[5] == 0x28)
strResponse += " $20";
else
strResponse += " unrecognized bill inserted";
}
else
if(RecvString[3] == 0x08)
strResponse = " - Stacking";
else
if(RecvString[3] == 0x10)
strResponse = " - Stacked";
else
if(RecvString[3] == 0x11)
strResponse = " - Returning";
else
if(RecvString[3] == 0x12)
strResponse = " - Returned";
//-- RecvString[4]------------------
if(RecvString[4] == 0x01)
strResponse += " - Cheated";
else
if(RecvString[4] == 0x02)
strResponse += " - Rejected";
else
if(RecvString[4] == 0x04)
strResponse += " - Jammed";
else
if(RecvString[4] == 0x08)
strResponse += " - Bill Stacker Full";
else
if(RecvString[4] == 0x10)
strResponse += " - Removable Cassette Installed";
else
if(RecvString[4] == 0x11)
strResponse += " - Reserved";
else
if(RecvString[4] == 0x12)
strResponse += " - Calibration mode";
//-- RecvString[5]------------------
if(RecvString[5] == 0x01)
strResponse += " - Power Up Reset";
else
if(RecvString[5] == 0x02)
strResponse += " - Invalid Command";
else
if(RecvString[5] == 0x04)
strResponse += " - Non-recoverable fault";
}
if(!strResponse.contains("Idling"))
System.out.println("Recv: " + DatatypeConverter.printHexBinary(RecvString) + strResponse);
}
else
{
System.out.println("Recv (invalid): " + DatatypeConverter.printHexBinary(RecvString));
}
try
{
Thread.sleep(100); // need this delay before we send next polling message, otherwise the data doesn't come in correctly
bReadyToSend = true;
}
catch (InterruptedException ex)
{
Thread.currentThread().interrupt();
//System.out.println("Shut down SerialReader thread.");
bShuttingDown = true;
break;
}
}
}
}
catch ( IOException ex )
{
System.out.println("Recv exception: " + ex.toString());
}
}
}
/* SerialWriter thread logic */
public static class SerialWriter implements Runnable
{
OutputStream out;
long lastSendTime = System.currentTimeMillis() - 1001;
long currSendTime;
byte[] SendString = new byte[8];
byte CheckDigit;
int iSendStringCount;
boolean bOddCount = true;
boolean bShuttingDown = false;
public SerialWriter ( OutputStream out )
{
this.out = out;
}
public void run ()
{
while(!bShuttingDown)
{
currSendTime = System.currentTimeMillis();
if(currSendTime - lastSendTime > 1000) // if it's been more than a second, send query string
bReadyToSend = true;
if(bReadyToSend)
{
SendString[0] = (byte) 0x02; //STX
SendString[1] = (byte) 0x08;
if(bOddCount)
{
SendString[2] = (byte) 0x10;
bOddCount = false;
}
else
{
SendString[2] = (byte) 0x11;
bOddCount = true;
}
SendString[3] = (byte) 0x7F;
SendString[4] = (byte) 0x1C;
SendString[5] = (byte) 0x00;
SendString[6] = (byte) 0x03; //ETX
//CheckDigit skips STX (byte 0) with byte 1 as seed/initial value
//To calculate the check digit, start with next byte (2)
CheckDigit = SendString[1];
iSendStringCount = 2;
while(SendString[iSendStringCount] != 0x03)
{
CheckDigit = (byte) (SendString[iSendStringCount]^CheckDigit); //XOR current CheckDigit value with next byte
iSendStringCount++;
}
iSendStringCount++; //advance one more so we don't overwrite ETX
SendString[iSendStringCount] = (byte) CheckDigit;
try
{
lastSendTime = System.currentTimeMillis();
this.out.write(SendString);
//System.out.println("Sent: " + DatatypeConverter.printHexBinary(SendString));
}
catch ( IOException ex )
{
System.out.println("Send exception: " + ex.toString());
}
try
{
Thread.sleep(1); // this is hear simply to catch an external interrupt
}
catch (InterruptedException ex)
{
Thread.currentThread().interrupt();
//System.out.println("Shut down SerialWriter thread.");
bShuttingDown = true;
break;
}
bReadyToSend = false;
}
}
}
}
public static void main ( String[] args )
{
try
{
System.out.println("*****************************");
System.out.println("***** Starting Program *****");
System.out.println("*****************************");
String strUsbDeviceDir = "/dev/serial/by-id";
File myUsbDeviceDir = new File(strUsbDeviceDir);
if(myUsbDeviceDir.exists())
{
String[] myUsbDevices = myUsbDeviceDir.list();
for(int i=0; i<myUsbDevices.length; i++)
{
if(myUsbDevices[i].contains("EBDS_over_USB"))
{
File tempFile = new File(strUsbDeviceDir + "/" + myUsbDevices[i]);
String usbCanonicalName = tempFile.getCanonicalFile().toString(); //gives me /dev/ttyUSBx where 'x' is the USB device number
System.out.println("Connecting to " + usbCanonicalName + " (" + myUsbDevices[i] + ")");
(new TwoWaySerialComm()).connect(usbCanonicalName);
}
else
{
System.out.println("Not using " + myUsbDevices[i]);
}
}
}
}
catch ( Exception ex )
{
System.out.println("Connect exception: " + ex.toString());
}
System.out.println("*****************************");
System.out.println("***** Program Finished ******");
System.out.println("*****************************");
}
Output when I put a $1 bill in (I'm developing/compiling from NetBeans IDE 8.2 on Windows 10 Pro and running using remote debugging on the RPi3. I'm guessing that's the source of the RXTX Version mismatch warning):
*****************************
***** Starting Program *****
*****************************
Connecting to /dev/ttyUSB0 (usb-Silicon_Labs_Series_2000_Bill_Acceptor__EBDS_over_USB__46580120748-if00-port0)
Stable Library
=========================================
Native lib Version = RXTX-2.2pre2
Java lib Version = RXTX-2.1-7
WARNING: RXTX Version mismatch
Jar version = RXTX-2.1-7
native lib Version = RXTX-2.2pre2
Recv (invalid): 020000000000000000000000
Recv (invalid): 0B2001100800503603540000
Recv: 020B20041008005036035100 - Escrowed $1 - Removable Cassette Installed
*****************************
***** Program Finished ******
*****************************
I hope this description and sample code can help someone else.

loadpixel() returns nullpointerexception

I was using processing in netbeans to play a movie on an array of ledstrips and I am using OPC.class for ledstrip fadecandy mapping. This code works on the processing sketch, but when I tried to use it on netbeans the loadpixel() in draw() method of OPC.java throws a nullpointer exception.
Stacktrace:
Exception in thread "Animation Thread" java.lang.NullPointerException
at processing.core.PApplet.loadPixels(PApplet.java:10625)
at com.processing.OPC.draw(OPC.java:139)
at com.processing.Video.draw(Video.java:62)
at processing.core.PApplet.handleDraw(PApplet.java:2402)
at processing.awt.PSurfaceAWT$12.callDraw(PSurfaceAWT.java:1527)
at processing.core.PSurfaceNone$AnimationThread.run(PSurfaceNone.java:316)
Video.java
public class Video extends PApplet
{
OPC opc;
Movie movie;
public static void main(String args[])
{
PApplet.main(new String[] { "--present", "com.processing.Video" });
}
public void settings()
{
size(600, 240);
}
public void setup()
{
opc = new OPC(this, "192.168.15.10", 7890);
for(int i=0; i<24; i++) {
opc.ledStrip(i * 60, 60,
300, i * 240 / 24 + 240 / 48, 240 / 24, PI, false);
}
movie = new Movie(this, "waffle.mp4");
movie.loop();
}
public void movieEvent(Movie m)
{
m.read();
}
#Override
public void draw()
{
if (movie.available() == true) {
movie.read();
}
image(movie, 0, 0, width, height);
}
}
OPC.java
public class OPC extends PApplet implements Runnable
{
Thread thread;
Socket socket;
OutputStream output, pending;
String host;
int port;
int height = 240;
int width = 600;
int[] pixelLocations;
byte[] packetData;
byte firmwareConfig;
String colorCorrection;
boolean enableShowLocations;
PApplet parent;
OPC(PApplet parent, String host, int port)
{
this.host = host;
this.port = port;
thread = new Thread(this);
thread.start();
this.enableShowLocations = true;
registerMethod("draw", this);
}
public void led(int index, int x, int y){
if (pixelLocations == null) {
pixelLocations = new int[index + 1];
} else if (index >= pixelLocations.length) {
pixelLocations = Arrays.copyOf(pixelLocations, index + 1);
}
pixelLocations[index] = x + 600 * y;
}
public void ledStrip(int index, int count, float x, float y, float spacing, float angle, boolean reversed)
{
float s = sin(angle);
float c = cos(angle);
for (int i = 0; i < count; i++) {
led(reversed ? (index + count - 1 - i) : (index + i),
(int)(x + (i - (count-1)/2.0) * spacing * c + 0.5),
(int)(y + (i - (count-1)/2.0) * spacing * s + 0.5));
}
}
void showLocations(boolean enabled)
{
enableShowLocations = enabled;
}
void setColorCorrection(String s)
{
colorCorrection = s;
sendColorCorrectionPacket();
}
void sendFirmwareConfigPacket()
{
if (pending == null) {
return;
}
byte[] packet = new byte[9];
packet[0] = (byte)0x00; // Channel (reserved)
packet[1] = (byte)0xFF; // Command (System Exclusive)
packet[2] = (byte)0x00; // Length high byte
packet[3] = (byte)0x05; // Length low byte
packet[4] = (byte)0x00; // System ID high byte
packet[5] = (byte)0x01; // System ID low byte
packet[6] = (byte)0x00; // Command ID high byte
packet[7] = (byte)0x02; // Command ID low byte
packet[8] = (byte)firmwareConfig;
try {
pending.write(packet);
} catch (Exception e) {
dispose();
}
}
void sendColorCorrectionPacket()
{
if (colorCorrection == null) {
return;
}
if (pending == null) {
return;
}
byte[] content = colorCorrection.getBytes();
int packetLen = content.length + 4;
byte[] header = new byte[8];
header[0] = (byte)0x00; // Channel (reserved)
header[1] = (byte)0xFF; // Command (System Exclusive)
header[2] = (byte)(packetLen >> 8); // Length high byte
header[3] = (byte)(packetLen & 0xFF); // Length low byte
header[4] = (byte)0x00; // System ID high byte
header[5] = (byte)0x01; // System ID low byte
header[6] = (byte)0x00; // Command ID high byte
header[7] = (byte)0x01; // Command ID low byte
try {
pending.write(header);
pending.write(content);
} catch (Exception e) {
dispose();
}
}
public void draw()
{
if (pixelLocations == null) {
return;
}
if (output == null) {
return;
}
int numPixels = pixelLocations.length;
int ledAddress = 4;
setPixelCount(numPixels);
println("pixel loading");
loadPixels();
println("pixel loaded123");
for (int i = 0; i < numPixels; i++) {
int pixelLocation = pixelLocations[i];
int pixel = pixels[pixelLocation];
packetData[ledAddress] = (byte)(pixel >> 16);
packetData[ledAddress + 1] = (byte)(pixel >> 8);
packetData[ledAddress + 2] = (byte)pixel;
ledAddress += 3;
if (true) {
pixels[pixelLocation] = 0xFFFFFF ^ pixel;
}
}
writePixels();
if (enableShowLocations) {
updatePixels();
print("a");
}
}
void setPixelCount(int numPixels)
{
int numBytes = 3 * numPixels;
int packetLen = 4 + numBytes;
if (packetData == null || packetData.length != packetLen) {
// Set up our packet buffer
packetData = new byte[packetLen];
packetData[0] = (byte)0x00;
packetData[1] = (byte)0x00;
packetData[2] = (byte)(numBytes >> 8);
packetData[3] = (byte)(numBytes & 0xFF);
}
}
void setPixel(int number, int c)
{
println("set");
int offset = 4 + number * 3;
if (packetData == null || packetData.length < offset + 3) {
setPixelCount(number + 1);
}
packetData[offset] = (byte) (c >> 16);
packetData[offset + 1] = (byte) (c >> 8);
packetData[offset + 2] = (byte) c;
}
int getPixel(int number)
{
println("get");
int offset = 4 + number * 3;
if (packetData == null || packetData.length < offset + 3) {
return 0;
}
return (packetData[offset] << 16) | (packetData[offset + 1] << 8) | packetData[offset + 2];
}
void writePixels()
{
println("write");
if (packetData == null || packetData.length == 0) {
return;
}
if (output == null) {
return;
}
try {
output.write(packetData);
} catch (Exception e) {
dispose();
}
}
public void dispose()
{
if (output != null) {
println("Disconnected from OPC server");
}
socket = null;
output = pending = null;
}
public void run()
{
println("?");
if(output == null) { // No OPC connection?
try { // Make one!
socket = new Socket(host, port);
socket.setTcpNoDelay(true);
pending = socket.getOutputStream();
println("Connected to OPC server");
sendColorCorrectionPacket();
sendFirmwareConfigPacket();
output = pending;
} catch (ConnectException e) {
dispose();
} catch (IOException e) {
dispose();
}
}
try {
Thread.sleep(500);
}
catch(InterruptedException e) {
}
}
}

You should only have one class that extends PApplet.
Think of that class as your "main" class. Any other classes that need to use Processing functions will need an instance of that main class in order to access Processing functions. You can pass it in using the this keyword.
In fact, you're already doing that- notice that you pass this into your OPC class, and then store it in the parent parameter. You just never do anything with that parameter.
So step 1 is to remove the extends PApplet from your OBC class:
public class OPC implements Runnable
This will cause some compilation errors. That's okay, we'll fix them later.
Step 2 is to actually store the PApplet parent parameter in a class-level variable.
OPC(PApplet parent, String host, int port){
this.parent = parent;
//rest of constructor
Now that you have that, step 3 is to fix any compilation errors by using the parent variable to access Processing functions.
parent.println("pixel loading");
parent.loadPixels();
More info can be found in the Processing in eclipse tutorial. It's for eclipse, but the same principles apply in netbeans.

write a program in java using modbus simulator for reading holding register values

I want to take real-time data using modbus tcp/ip simulator for filling of a tank that uses port no 502.
How can I write a code in java to get the holding register value from the simulator and also I want to control the values of it?

If you use a Modbus library like this one most of the work is already done for you.
ModbusTcpMasterConfig config = new ModbusTcpMasterConfig.Builder("localhost").build();
ModbusTcpMaster master = new ModbusTcpMaster(config);
CompletableFuture<ReadHoldingRegistersResponse> future =
master.sendRequest(new ReadHoldingRegistersRequest(0, 10), 0);
future.thenAccept(response -> {
System.out.println("Response: " + ByteBufUtil.hexDump(response.getRegisters()));
ReferenceCountUtil.release(response);
});

import java.io.* ;
import java.net.* ;
import java.util.*;
public class Modcli {
public static void main(String argv[]) {
if (argv.length < 4) {
System.out.println("usage: java test3 dns_name unit reg_no num_regs");
System.out.println("eg java test3 aswales8.modicon.com 5 0 10");
return;
}
try {
String ip_adrs = argv[0];
int unit = Integer.parseInt(argv[1]);
int reg_no = Integer.parseInt(argv[2]);
int num_regs = Integer.parseInt(argv[3]);
System.out.println("ip_adrs = "+ip_adrs+" unit = "+unit+" reg_no = "+
reg_no+" num_regs = "+num_regs);
// set up socket
Socket es = new Socket(ip_adrs,502);
OutputStream os= es.getOutputStream();
FilterInputStream is = new BufferedInputStream(es.getInputStream());
byte obuf[] = new byte[261];
byte ibuf[] = new byte[261];
int c = 0;
int i;
// build request of form 0 0 0 0 0 6 ui 3 rr rr nn nn
for (i=0;i<5;i++) obuf[i] = 0;
obuf[5] = 6;
obuf[6] = (byte)unit;
obuf[7] = 3;
obuf[8] = (byte)(reg_no >> 8);
obuf[9] = (byte)(reg_no & 0xff);
obuf[10] = (byte)(num_regs >> 8);
obuf[11] = (byte)(num_regs & 0xff);
// send request
os.write(obuf, 0, 12);
// read response
i = is.read(ibuf, 0, 261);
if (i<9) {
if (i==0) {
System.out.println("unexpected close of connection at remote end");
} else {
System.out.println("response was too short - "+i+" chars");
}
} else if (0 != (ibuf[7] & 0x80)) {
System.out.println("MODBUS exception response - type "+ibuf[8]);
} else if (i != (9+2*num_regs)) {
System.out.println("incorrect response size is "+i+
" expected"+(9+2*num_regs));
} else {
for (i=0;i<=2;i++) {
int w = (ibuf[0+i+i]<<8) + ibuf[1+i+i];
System.out.println("word "+i+" = "+w);
}
for (i=3;i<=5;i++) {
int w = (ibuf[i+3]) ;
System.out.println("word "+i+" = "+w);
}
for (i=0;i<num_regs;i++) {
int w = (ibuf[9+i+i]<<8) + ibuf[10+i+i];
System.out.println("word "+i+" = "+w);
}
}
// close down
es.close();
} catch (Exception e) {
System.out.println("exception :"+e);
}
}
}