SVGHMI: use requestAnimationFrame to delegate rendering of updates from network. Should help prevent browser collapse leading to watchdog in case of overload.
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<project xmlns:ns1="http://www.plcopen.org/xml/tc6_0201" xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://www.plcopen.org/xml/tc6_0201">
<fileHeader companyName="Beremiz" productName="Beremiz" productVersion="1" creationDateTime="2018-07-27T13:19:12"/>
<contentHeader name="Modbus" modificationDateTime="2018-07-27T15:43:56">
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<fbd>
<scaling x="0" y="0"/>
</fbd>
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<scaling x="0" y="0"/>
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</coordinateInfo>
</contentHeader>
<types>
<dataTypes/>
<pous>
<pou name="program0" pouType="program">
<interface>
<localVars>
<variable name="Counter">
<type>
<INT/>
</type>
</variable>
<variable name="CounterReadBack">
<type>
<INT/>
</type>
</variable>
</localVars>
<localVars>
<variable name="MasterWriteToReg0" address="%QW0.0.0.0">
<type>
<INT/>
</type>
</variable>
<variable name="MasterReadFromReg1" address="%IW0.0.1.0">
<type>
<INT/>
</type>
</variable>
<variable name="SlaveHoldReg0" address="%IW0.1.0.0">
<type>
<WORD/>
</type>
</variable>
<variable name="SlaveInputReg0" address="%QW0.1.1.0">
<type>
<WORD/>
</type>
</variable>
</localVars>
<localVars>
<variable name="CTU0">
<type>
<derived name="CTU"/>
</type>
</variable>
<variable name="Generator0">
<type>
<derived name="Generator"/>
</type>
</variable>
</localVars>
</interface>
<body>
<FBD>
<comment localId="4" height="109" width="350">
<position x="102" y="438"/>
<content>
<xhtml:p><![CDATA[Modbus TCP Master writes counter value to one holding register on Modbus TCP Slave and reads it back from other input register.]]></xhtml:p>
</content>
</comment>
<comment localId="3" height="407" width="680">
<position x="21" y="15"/>
<content>
<xhtml:p><![CDATA[This examples shows how to work with Modbus extension. It uses Modbus TCP, but the same functions are available for Modbus RTU as well. Buth protocols are supported.
Modbus extensions requires native Modbus RTU/TCP library to be installed nearby Beremiz.
Following directory structure is expected:
<Parent directory>
"beremiz"
"Modbus"
If Modbus library is installed elsewhere, then place corresponding paths
in CFLAGS/LDFLAGS in project settings.
For GNU/Linux to install Modbus library in parent directory run following commands:
$ hg clone https://bitbucket.org/mjsousa/modbus Modbus
$ cd Modbus
$ make
After that Modbus extension is ready to be used in Beremiz projects.]]></xhtml:p>
</content>
</comment>
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<position x="346" y="605"/>
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<variable formalParameter="CU" edge="rising">
<connectionPointIn>
<relPosition x="0" y="30"/>
<connection refLocalId="6" formalParameter="OUT">
<position x="346" y="635"/>
<position x="303" y="635"/>
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<variable formalParameter="R">
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<position x="324" y="675"/>
<position x="324" y="703"/>
<position x="302" y="703"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="Q">
<connectionPointOut>
<relPosition x="52" y="30"/>
</connectionPointOut>
</variable>
<variable formalParameter="CV">
<connectionPointOut>
<relPosition x="52" y="50"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<block localId="6" typeName="Generator" instanceName="Generator0" executionOrderId="0" height="60" width="79">
<position x="224" y="605"/>
<inputVariables>
<variable formalParameter="PON">
<connectionPointIn>
<relPosition x="0" y="30"/>
<connection refLocalId="1">
<position x="224" y="635"/>
<position x="154" y="635"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="POFF">
<connectionPointIn>
<relPosition x="0" y="50"/>
<connection refLocalId="1">
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<position x="189" y="655"/>
<position x="189" y="635"/>
<position x="154" y="635"/>
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<variable formalParameter="OUT">
<connectionPointOut>
<relPosition x="79" y="30"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
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<position x="16" y="620"/>
<connectionPointOut>
<relPosition x="138" y="15"/>
</connectionPointOut>
<expression>T#1s</expression>
</inVariable>
<inVariable localId="7" executionOrderId="0" height="30" width="138" negated="false">
<position x="164" y="688"/>
<connectionPointOut>
<relPosition x="138" y="15"/>
</connectionPointOut>
<expression>32767</expression>
</inVariable>
<inOutVariable localId="2" executionOrderId="0" height="30" width="138" negatedOut="false" negatedIn="false">
<position x="544" y="640"/>
<connectionPointIn>
<relPosition x="0" y="15"/>
<connection refLocalId="5" formalParameter="CV">
<position x="544" y="655"/>
<position x="398" y="655"/>
</connection>
</connectionPointIn>
<connectionPointOut>
<relPosition x="138" y="15"/>
</connectionPointOut>
<expression>Counter</expression>
</inOutVariable>
<outVariable localId="8" executionOrderId="0" height="30" width="138" negated="false">
<position x="762" y="640"/>
<connectionPointIn>
<relPosition x="0" y="15"/>
<connection refLocalId="2">
<position x="762" y="655"/>
<position x="682" y="655"/>
</connection>
</connectionPointIn>
<expression>MasterWriteToReg0</expression>
</outVariable>
<inVariable localId="9" executionOrderId="0" height="30" width="152" negated="false">
<position x="81" y="747"/>
<connectionPointOut>
<relPosition x="152" y="15"/>
</connectionPointOut>
<expression>MasterReadFromReg1</expression>
</inVariable>
<outVariable localId="10" executionOrderId="0" height="30" width="137" negated="false">
<position x="547" y="747"/>
<connectionPointIn>
<relPosition x="0" y="15"/>
<connection refLocalId="9">
<position x="547" y="762"/>
<position x="233" y="762"/>
</connection>
</connectionPointIn>
<expression>CounterReadBack</expression>
</outVariable>
<comment localId="11" height="109" width="350">
<position x="85" y="825"/>
<content>
<xhtml:p><![CDATA[Modbus TCP Slave just copies received register value from holding register to input register.]]></xhtml:p>
</content>
</comment>
<inVariable localId="12" executionOrderId="0" height="30" width="152" negated="false">
<position x="82" y="970"/>
<connectionPointOut>
<relPosition x="152" y="15"/>
</connectionPointOut>
<expression>SlaveHoldReg0</expression>
</inVariable>
<outVariable localId="13" executionOrderId="0" height="30" width="123" negated="false">
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<connectionPointIn>
<relPosition x="0" y="15"/>
<connection refLocalId="12">
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<position x="234" y="985"/>
</connection>
</connectionPointIn>
<expression>SlaveInputReg0</expression>
</outVariable>
</FBD>
</body>
</pou>
<pou name="Generator" pouType="functionBlock">
<interface>
<outputVars>
<variable name="OUT">
<type>
<BOOL/>
</type>
</variable>
</outputVars>
<inputVars>
<variable name="PON">
<type>
<TIME/>
</type>
</variable>
<variable name="POFF">
<type>
<TIME/>
</type>
</variable>
</inputVars>
<localVars>
<variable name="T1">
<type>
<derived name="TON"/>
</type>
</variable>
<variable name="T2">
<type>
<derived name="TOF"/>
</type>
</variable>
</localVars>
</interface>
<body>
<ST>
<xhtml:p><![CDATA[T1( IN := NOT T2.Q, PT := POFF);
T2( IN := T1.Q, PT := PON);
OUT := T2.Q;]]></xhtml:p>
</ST>
</body>
</pou>
</pous>
</types>
<instances>
<configurations>
<configuration name="config">
<resource name="resource1">
<task name="task0" priority="0" interval="T#20ms">
<pouInstance name="instance0" typeName="program0"/>
</task>
</resource>
</configuration>
</configurations>
</instances>
</project>