Writing multiple variables with sumcommando
Description
This sample shows how to write multiple variables by use of a write sumcommando.
 | Transporting bigger data packets Generally, HTTP-traffic is more efficient by transporting bigger data packets instead of many small packets. Therefore, please use ADS sum commandos to collect your data. |
ToDo:
- Download the TcAdsJavaScript.js_Sample02.zip
- Start the PLC project
- Copy the default.htm and TcAdsWebService.js to your cofigured virtual directory
- Adjust NETID, PORT and SERVICE_URL if you use the TcAdsWebservice of a remote pc
<!DOCTYPE html>
<html>
<head>
<title>TcAdsWebService.js Sample01</title>
<script type="text/javascript" src="TcAdsWebService.js"></script>
<script type="text/javascript">
(function () {
var NETID = ""; // Empty string for local machine;
var PORT = "801"; // TC2 PLC Runtime = 801, TC3 PLC Runtime = 851
var SERVICE_URL = "http://localhost/TcAdsWebService/TcAdsWebService.dll"; // HTTP path to the TcAdsWebService;
var client = new TcAdsWebService.Client(SERVICE_URL, null, null);
var general_timeout = 500;
// Array of symbol names to read;
var handlesVarNames = [
"MAIN.byteValue",
"MAIN.wordValue",
"MAIN.dwordValue",
"MAIN.sintValue",
"MAIN.intValue",
"MAIN.dintValue",
"MAIN.realValue",
"MAIN.lrealValue"
];
var handlesVarSizes = [ 1, 2, 4, 1, 2, 4, 4, 8 ];
var handles = [];
// Occurs if the window has loaded;
window.onload = (function () {
// Register ui events
btnWrite.onclick = BtnWriteClicked;
// Create sumcommando for reading twincat symbol handles by symbol name;
var handleswriter = new TcAdsWebService.DataWriter();
// Write general information for each symbol handle to the TcAdsWebService.DataWriter object;
for (var i = 0; i < handlesVarNames.length; i++) {
handleswriter.writeDINT(TcAdsWebService.TcAdsReservedIndexGroups.SymbolHandleByName);
handleswriter.writeDINT(0);
handleswriter.writeDINT(4); // Expected size; A handle has a size of 4 byte;
handleswriter.writeDINT(handlesVarNames[i].length); // The length of the symbol name string;
}
// Write symbol names after the general information to the TcAdsWebService.DataWriter object;
for (var i = 0; i < handlesVarNames.length; i++) {
handleswriter.writeString(handlesVarNames[i]);
}
// Send the list-read-write command to the TcAdsWebService by use of the readwrite function of the TcAdsWebService.Client object;
client.readwrite(
NETID,
PORT,
0xF082, // IndexGroup = ADS list-read-write command; Used to request handles for twincat symbols;
handlesVarNames.length, // IndexOffset = Count of requested symbol handles;
(handlesVarNames.length * 4) + (handlesVarNames.length * 8), // Length of requested data + 4 byte errorcode and 4 byte length per twincat symbol;
handleswriter.getBase64EncodedData(),
RequestHandlesCallback,
null,
general_timeout,
RequestHandlesTimeoutCallback,
true);
});
// Occurs if the readwrite for the sumcommando has finished;
var RequestHandlesCallback = (function (e, s) {
if (e && e.isBusy) {
// HANDLE PROGRESS TASKS HERE;
var message = "Requesting symbol handles...";
div_log.innerHTML = message;
// Exit callback function because request is still busy;
return;
}
if (e && !e.hasError) {
// Get TcAdsWebService.DataReader object from TcAdsWebService.Response object;
var reader = e.reader;
// Read error code and length for each handle;
for (var i = 0; i < handlesVarNames.length; i++) {
var err = reader.readDWORD();
var len = reader.readDWORD();
if (err != 0) {
div_log.innerHTML = "Symbol handle error!";
return;
}
}
var message = "Symbol handles successfully created!";
div_log.innerHTML = message;
// Read handles from TcAdsWebService.DataReader object;
handles[0] = reader.readDWORD();
handles[1] = reader.readDWORD();
handles[2] = reader.readDWORD();
handles[3] = reader.readDWORD();
handles[4] = reader.readDWORD();
handles[5] = reader.readDWORD();
handles[6] = reader.readDWORD();
handles[7] = reader.readDWORD();
} else {
if (e.error.getTypeString() == "TcAdsWebService.ResquestError") {
// HANDLE TcAdsWebService.ResquestError HERE;
div_log.innerHTML = "Error: StatusText = " + e.error.statusText + " Status: " + e.error.status;
}
else if (e.error.getTypeString() == "TcAdsWebService.Error") {
// HANDLE TcAdsWebService.Error HERE;
div_log.innerHTML = "Error: ErrorMessage = " + e.error.errorMessage + " ErrorCode: " + e.error.errorCode;
}
}
});
// Occurs if the readwrite for the sumcommando to request symbol handles runs into timeout;
var RequestHandlesTimeoutCallback = (function () {
// HANDLE TIMEOUT HERE;
div_log.innerHTML = "Requuest symbol handles timeout!";
});
var BtnWriteClicked = (function () {
// Create TcAdsWebService.DataWriter for write-read-write command.
var writer = new TcAdsWebService.DataWriter();
// Write general write-read-write commando information to TcAdsWebService.DataWriter object;
var size = 0;
for (var i = 0; i < handles.length; i++) {
writer.writeDINT(TcAdsWebService.TcAdsReservedIndexGroups.SymbolValueByHandle);
writer.writeDINT(handles[i]);
writer.writeDINT(handlesVarSizes[i]);
size = size + handlesVarSizes[i];
}
// Write values to TcAdsWebService.DataWrite object;
writer.writeBYTE(parseFloat(Text1.value));
writer.writeWORD(parseFloat(Text2.value));
writer.writeDWORD(parseFloat(Text3.value));
writer.writeSINT(parseFloat(Text4.value));
writer.writeINT(parseFloat(Text5.value));
writer.writeDINT(parseFloat(Text6.value));
writer.writeREAL(parseFloat(Text7.value));
writer.writeLREAL(parseFloat(Text8.value));
client.readwrite(
NETID,
PORT,
0xF081, // 0xF081 = Call Write SumCommando
handles.length, // IndexOffset = Count of requested variables.
size+(handles.length*4), // Length of requested data + 4 byte errorcode per variable.
writer.getBase64EncodedData(),
WriteCallback,
null,
general_timeout,
WriteTimeoutCallback,
true);
});
var WriteCallback = (function(e,s){
if (e && e.isBusy) {
// HANDLE PROGRESS TASKS HERE;
var message = "Writing data to plc...";
div_log.innerHTML = message;
// Exit callback function because request is still busy;
return;
}
if (e && !e.hasError) {
var message = "Writing data successfully finished...";
div_log.innerHTML = message;
} else {
if (e.error.getTypeString() == "TcAdsWebService.ResquestError") {
// HANDLE TcAdsWebService.ResquestError HERE;
div_log.innerHTML = "Error: StatusText = " + e.error.statusText + " Status: " + e.error.status;
}
else if (e.error.getTypeString() == "TcAdsWebService.Error") {
// HANDLE TcAdsWebService.Error HERE;
div_log.innerHTML = "Error: ErrorMessage = " + e.error.errorMessage + " ErrorCode: " + e.error.errorCode;
}
}
});
// Occurs if the write-read-write command runs into timeout;
var WriteTimeoutCallback = (function () {
// HANDLE TIMEOUT HERE;
div_log.innerHTML = "Write timeout!";
});
})();
</script>
</head>
<body>
<h1>TcAdsWebService.js Sample02</h1>
<h2>Write multiple variables with sumcommando!</h2>
<table>
<tr>
<td>MAIN.byteValue:</td>
<td><input id="Text1" type="text" /></td>
</tr>
<tr>
<td>MAIN.wordValue:</td>
<td><input id="Text2" type="text" /></td>
</tr>
<tr>
<td>MAIN.dwordValue:</td>
<td><input id="Text3" type="text" /></td>
</tr>
<tr>
<td>MAIN.sintValue:</td>
<td><input id="Text4" type="text" /></td>
</tr>
<tr>
<td>MAIN.intValue:</td>
<td><input id="Text5" type="text" /></td>
</tr>
<tr>
<td>MAIN.dintValue:</td>
<td><input id="Text6" type="text" /></td>
</tr>
<tr>
<td>MAIN.realValue:</td>
<td><input id="Text7" type="text" /></td>
</tr>
<tr>
<td>MAIN.lrealValue:</td>
<td><input id="Text8" type="text" /></td>
</tr>
</table>
<input type="button" id="btnWrite" value="Write Values to PLC" />
<div id="div_log"></div>
</body>
</html>