More canonical test.
There is an exception happening around here in some cases when connection is dropped while waiting for answer. Not sure that this fixes it but this is anyhow better.
<?xml version='1.0' encoding='utf-8'?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.plcopen.org/xml/tc6_0201" xmlns:xhtml="http://www.w3.org/1999/xhtml" xsi:schemaLocation="http://www.plcopen.org/xml/tc6_0201">
<fileHeader companyName="beremiz" productName="Beremiz" productVersion="0.0" creationDateTime="2008-12-14T16:21:19"/>
<contentHeader name="Beremiz wxHMI test" modificationDateTime="2017-06-05T14:01:40">
<coordinateInfo>
<pageSize x="1024" y="1024"/>
<fbd>
<scaling x="5" y="5"/>
</fbd>
<ld>
<scaling x="5" y="5"/>
</ld>
<sfc>
<scaling x="5" y="5"/>
</sfc>
</coordinateInfo>
</contentHeader>
<types>
<dataTypes/>
<pous>
<pou name="main_pytest" pouType="program">
<interface>
<localVars>
<variable name="getCheckBoxState">
<type>
<derived name="python_poll"/>
</type>
</variable>
<variable name="counter">
<type>
<INT/>
</type>
</variable>
<variable name="setSpinCtrlValue">
<type>
<derived name="python_poll"/>
</type>
</variable>
</localVars>
</interface>
<body>
<FBD>
<block localId="24" width="125" height="90" typeName="python_poll" instanceName="getCheckBoxState" executionOrderId="0">
<position x="480" y="215"/>
<inputVariables>
<variable formalParameter="TRIG">
<connectionPointIn>
<relPosition x="0" y="35"/>
<connection refLocalId="25">
<position x="480" y="250"/>
<position x="420" y="250"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="CODE">
<connectionPointIn>
<relPosition x="0" y="70"/>
<connection refLocalId="26">
<position x="480" y="285"/>
<position x="420" y="285"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="ACK">
<connectionPointOut>
<relPosition x="125" y="35"/>
</connectionPointOut>
</variable>
<variable formalParameter="RESULT">
<connectionPointOut>
<relPosition x="125" y="70"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<inVariable localId="25" height="30" width="100" executionOrderId="0" negated="false">
<position x="320" y="235"/>
<connectionPointOut>
<relPosition x="100" y="15"/>
</connectionPointOut>
<expression>BOOL#TRUE</expression>
</inVariable>
<inVariable localId="26" height="30" width="400" executionOrderId="0" negated="false">
<position x="20" y="270"/>
<connectionPointOut>
<relPosition x="400" y="15"/>
</connectionPointOut>
<expression>'int(HMIFrame.checkbox_1.GetValue())'</expression>
</inVariable>
<inVariable localId="27" height="30" width="40" executionOrderId="0" negated="false">
<position x="535" y="505"/>
<connectionPointOut>
<relPosition x="40" y="15"/>
</connectionPointOut>
<expression>')'</expression>
</inVariable>
<inVariable localId="28" height="30" width="330" executionOrderId="0" negated="false">
<position x="150" y="415"/>
<connectionPointOut>
<relPosition x="330" y="15"/>
</connectionPointOut>
<expression>'HMIFrame.spin_ctrl_1.SetValue('</expression>
</inVariable>
<block localId="30" width="145" height="85" typeName="STRING_TO_INT" executionOrderId="0">
<position x="670" y="215"/>
<inputVariables>
<variable formalParameter="EN">
<connectionPointIn>
<relPosition x="0" y="35"/>
<connection refLocalId="24" formalParameter="ACK">
<position x="670" y="250"/>
<position x="605" y="250"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="IN">
<connectionPointIn>
<relPosition x="0" y="70"/>
<connection refLocalId="24" formalParameter="RESULT">
<position x="670" y="285"/>
<position x="605" y="285"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="ENO">
<connectionPointOut>
<relPosition x="145" y="35"/>
</connectionPointOut>
</variable>
<variable formalParameter="OUT">
<connectionPointOut>
<relPosition x="145" y="70"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<block localId="32" width="80" height="80" typeName="ADD" executionOrderId="0">
<position x="135" y="450"/>
<inputVariables>
<variable formalParameter="EN">
<connectionPointIn>
<relPosition x="0" y="30"/>
<connection refLocalId="38" formalParameter="OUT">
<position x="135" y="480"/>
<position x="100" y="480"/>
<position x="100" y="330"/>
<position x="1140" y="330"/>
<position x="1140" y="250"/>
<position x="1130" y="250"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="IN1">
<connectionPointIn>
<relPosition x="0" y="50"/>
<connection refLocalId="39">
<position x="135" y="500"/>
<position x="90" y="500"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="IN2">
<connectionPointIn>
<relPosition x="0" y="70"/>
<connection refLocalId="33">
<position x="135" y="520"/>
<position x="125" y="520"/>
<position x="125" y="540"/>
<position x="340" y="540"/>
<position x="340" y="500"/>
<position x="320" y="500"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="ENO">
<connectionPointOut>
<relPosition x="80" y="30"/>
</connectionPointOut>
</variable>
<variable formalParameter="OUT">
<connectionPointOut>
<relPosition x="80" y="50"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<block localId="34" width="80" height="100" typeName="CONCAT" executionOrderId="0">
<position x="605" y="430"/>
<inputVariables>
<variable formalParameter="EN">
<connectionPointIn>
<relPosition x="0" y="30"/>
<connection refLocalId="35" formalParameter="ENO">
<position x="605" y="460"/>
<position x="520" y="460"/>
<position x="520" y="480"/>
<position x="500" y="480"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="IN1">
<connectionPointIn>
<relPosition x="0" y="50"/>
<connection refLocalId="28">
<position x="605" y="480"/>
<position x="562" y="480"/>
<position x="562" y="430"/>
<position x="480" y="430"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="IN2">
<connectionPointIn>
<relPosition x="0" y="70"/>
<connection refLocalId="35" formalParameter="OUT">
<position x="605" y="500"/>
<position x="500" y="500"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="IN3">
<connectionPointIn>
<relPosition x="0" y="90"/>
<connection refLocalId="27">
<position x="605" y="520"/>
<position x="575" y="520"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="ENO">
<connectionPointOut>
<relPosition x="80" y="30"/>
</connectionPointOut>
</variable>
<variable formalParameter="OUT">
<connectionPointOut>
<relPosition x="80" y="50"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<inOutVariable localId="33" height="35" width="85" executionOrderId="0" negatedOut="false" negatedIn="false">
<position x="235" y="485"/>
<connectionPointIn>
<relPosition x="0" y="15"/>
<connection refLocalId="32" formalParameter="OUT">
<position x="235" y="500"/>
<position x="215" y="500"/>
</connection>
</connectionPointIn>
<connectionPointOut>
<relPosition x="85" y="15"/>
</connectionPointOut>
<expression>counter</expression>
</inOutVariable>
<block localId="35" width="145" height="60" typeName="INT_TO_STRING" executionOrderId="0">
<position x="355" y="450"/>
<inputVariables>
<variable formalParameter="EN">
<connectionPointIn>
<relPosition x="0" y="30"/>
<connection refLocalId="32" formalParameter="ENO">
<position x="355" y="480"/>
<position x="215" y="480"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="IN">
<connectionPointIn>
<relPosition x="0" y="50"/>
<connection refLocalId="33">
<position x="355" y="500"/>
<position x="320" y="500"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="ENO">
<connectionPointOut>
<relPosition x="145" y="30"/>
</connectionPointOut>
</variable>
<variable formalParameter="OUT">
<connectionPointOut>
<relPosition x="145" y="50"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<block localId="36" width="125" height="90" typeName="python_poll" instanceName="setSpinCtrlValue" executionOrderId="0">
<position x="735" y="425"/>
<inputVariables>
<variable formalParameter="TRIG">
<connectionPointIn>
<relPosition x="0" y="35"/>
<connection refLocalId="34" formalParameter="ENO">
<position x="735" y="460"/>
<position x="685" y="460"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="CODE">
<connectionPointIn>
<relPosition x="0" y="70"/>
<connection refLocalId="34" formalParameter="OUT">
<position x="735" y="495"/>
<position x="715" y="495"/>
<position x="715" y="480"/>
<position x="685" y="480"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="ACK">
<connectionPointOut>
<relPosition x="125" y="35"/>
</connectionPointOut>
</variable>
<variable formalParameter="RESULT">
<connectionPointOut>
<relPosition x="125" y="70"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<block localId="37" width="125" height="45" typeName="INT_TO_BOOL" executionOrderId="0">
<position x="870" y="255"/>
<inputVariables>
<variable formalParameter="IN">
<connectionPointIn>
<relPosition x="0" y="30"/>
<connection refLocalId="30" formalParameter="OUT">
<position x="870" y="285"/>
<position x="815" y="285"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="OUT">
<connectionPointOut>
<relPosition x="125" y="30"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<block localId="38" width="80" height="95" typeName="AND" executionOrderId="0">
<position x="1050" y="210"/>
<inputVariables>
<variable formalParameter="IN1">
<connectionPointIn>
<relPosition x="0" y="40"/>
<connection refLocalId="30" formalParameter="ENO">
<position x="1050" y="250"/>
<position x="815" y="250"/>
</connection>
</connectionPointIn>
</variable>
<variable formalParameter="IN2">
<connectionPointIn>
<relPosition x="0" y="75"/>
<connection refLocalId="37" formalParameter="OUT">
<position x="1050" y="285"/>
<position x="995" y="285"/>
</connection>
</connectionPointIn>
</variable>
</inputVariables>
<inOutVariables/>
<outputVariables>
<variable formalParameter="OUT">
<connectionPointOut>
<relPosition x="80" y="40"/>
</connectionPointOut>
</variable>
</outputVariables>
</block>
<inVariable localId="39" height="30" width="60" executionOrderId="0" negated="false">
<position x="30" y="485"/>
<connectionPointOut>
<relPosition x="60" y="15"/>
</connectionPointOut>
<expression>INT#1</expression>
</inVariable>
<comment localId="101" height="115" width="680">
<position x="10" y="30"/>
<content>
<xhtml:p><![CDATA[This example shows how IEC program in PLC can interact with UI created using wxGlade.
"WxGlade GUI" is extension to build user interface for PLC using wxGlade.
To edit user interface click on "WxGlade" icon in extension settings.]]></xhtml:p>
</content>
</comment>
</FBD>
</body>
</pou>
</pous>
</types>
<instances>
<configurations>
<configuration name="config">
<resource name="res_pytest">
<task name="pytest_task" interval="t#100ms" priority="0"/>
<pouInstance name="pytest_instance" typeName="main_pytest"/>
</resource>
</configuration>
</configurations>
</instances>
</project>