allows GAL signal pass through, see #390

src/main/java/de/neemann/digital/builder/BuilderCollector.java

@@ -80,4 +80,12 @@ public class BuilderCollector implements BuilderInterface<BuilderCollector> {
         return registered;
     }
 
+    /**
+     * Removes an output.
+     *
+     * @param name the output to remove
+     */
+    public void removeOutput(String name) {
+        outputs.remove(name);
+    }
 }

src/main/java/de/neemann/digital/builder/Gal16v8/BuilderCollectorGAL.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2019 Helmut Neemann.
+ * Use of this source code is governed by the GPL v3 license
+ * that can be found in the LICENSE file.
+ */
+package de.neemann.digital.builder.Gal16v8;
+
+import de.neemann.digital.analyse.expression.Expression;
+import de.neemann.digital.builder.BuilderCollector;
+import de.neemann.digital.builder.BuilderException;
+import de.neemann.digital.builder.PinMap;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Map;
+
+/**
+ * Used to avoid a double cell allocation if the output of a ff is used as a autput of the state machine.
+ * This is the case if a Moore machine is build where the state equals the output.
+ * Sometimes this kind of state machines is called a Medwedew machine.
+ */
+public class BuilderCollectorGAL extends BuilderCollector {
+    private final PinMap pinMap;
+    private HashSet<String> sequentialVars;
+    private boolean doubleCellUsageFixed = false;
+
+    /**
+     * Creates a new instance
+     *
+     * @param pinMap the used pinMap. Is required to handle aliases correctly
+     */
+    public BuilderCollectorGAL(PinMap pinMap) {
+        this.pinMap = pinMap;
+        sequentialVars = new HashSet<>();
+    }
+
+    @Override
+    public BuilderCollector addCombinatorial(String name, Expression expression) throws BuilderException {
+        checkOpen();
+        return super.addCombinatorial(name, expression);
+    }
+
+    @Override
+    public BuilderCollector addSequential(String name, Expression expression) throws BuilderException {
+        checkOpen();
+        sequentialVars.add(name);
+        return super.addSequential(name, expression);
+    }
+
+    private void checkOpen() {
+        if (doubleCellUsageFixed)
+            throw new RuntimeException("wrong BuilderCollectorGAL usage!");
+    }
+
+    private void fixDoubleCellUsage() {
+        if (!doubleCellUsageFixed) {
+
+            super.getCombinatorial().entrySet().removeIf(c -> {
+                if (pinMap.isSimpleAlias(c.getKey(), c.getValue(), sequentialVars)) {
+                    removeOutput(c.getKey());
+                    return true;
+                }
+                return false;
+            });
+
+            doubleCellUsageFixed = true;
+        }
+    }
+
+    @Override
+    public ArrayList<String> getOutputs() {
+        fixDoubleCellUsage();
+        return super.getOutputs();
+    }
+
+    @Override
+    public ArrayList<String> getInputs() {
+        fixDoubleCellUsage();
+        return super.getInputs();
+    }
+
+    @Override
+    public Map<String, Expression> getCombinatorial() {
+        fixDoubleCellUsage();
+        return super.getCombinatorial();
+    }
+
+    @Override
+    public Map<String, Expression> getRegistered() {
+        fixDoubleCellUsage();
+        return super.getRegistered();
+    }
+}

src/main/java/de/neemann/digital/builder/Gal16v8/CuplExporter.java

@@ -84,7 +84,7 @@ public class CuplExporter implements ExpressionExporter<CuplExporter> {
         this.date = date;
         this.devName = devName;
         this.pinMap = pinMap;
-        builder = new CuplBuilder();
+        builder = new CuplBuilder(pinMap);
         cleanNameBuilder = new CleanNameBuilder(builder);
     }
 
@@ -228,14 +228,15 @@ public class CuplExporter implements ExpressionExporter<CuplExporter> {
     protected void sequentialWritten(Writer out, String name) throws IOException {
     }
 
-    private final class CuplBuilder extends BuilderCollector {
+    private static final class CuplBuilder extends BuilderCollectorGAL {
         private final NotAllowedVariablesVisitor notAllowedVariablesVisitor = new NotAllowedVariablesVisitor();
 
+        private CuplBuilder(PinMap pinMap) {
+            super(pinMap);
+        }
+
         @Override
         public BuilderCollector addCombinatorial(String name, Expression expression) throws BuilderException {
-            if (pinMap.isSimpleAlias(name, expression))
-                return this;  // ignore simple variables!
-
             expression.traverse(notAllowedVariablesVisitor);
             notAllowedVariablesVisitor.check(name);
             return super.addCombinatorial(name, expression);

src/main/java/de/neemann/digital/builder/Gal16v8/Gal16v8JEDECExporter.java

@@ -5,9 +5,11 @@
  */
 package de.neemann.digital.builder.Gal16v8;
 
-import de.neemann.digital.analyse.expression.Expression;
 import de.neemann.digital.analyse.expression.Variable;
-import de.neemann.digital.builder.*;
+import de.neemann.digital.builder.BuilderCollector;
+import de.neemann.digital.builder.ExpressionExporter;
+import de.neemann.digital.builder.PinMap;
+import de.neemann.digital.builder.PinMapException;
 import de.neemann.digital.builder.jedec.FuseMap;
 import de.neemann.digital.builder.jedec.FuseMapFiller;
 import de.neemann.digital.builder.jedec.FuseMapFillerException;
@@ -43,18 +45,10 @@ public class Gal16v8JEDECExporter implements ExpressionExporter<Gal16v8JEDECExpo
             map.setFuse(i, true);
         filler = new FuseMapFiller(map, 16);
 
-        builder = new BuilderCollector() {
-            @Override
-            public BuilderCollector addCombinatorial(String name, Expression expression) throws BuilderException {
-                if (pinMap.isSimpleAlias(name, expression))
-                    return this;
-                else
-                    return super.addCombinatorial(name, expression);
-            }
-        };
         pinMap = new PinMap()
                 .setAvailInputs(2, 3, 4, 5, 6, 7, 8, 9)
                 .setAvailOutputs(12, 13, 14, 15, 16, 17, 18, 19);
+        builder = new BuilderCollectorGAL(pinMap);
     }
 
     private void init(boolean registered) {

src/main/java/de/neemann/digital/builder/Gal22v10/Gal22v10JEDECExporter.java

@@ -5,9 +5,9 @@
  */
 package de.neemann.digital.builder.Gal22v10;
 
-import de.neemann.digital.analyse.expression.Expression;
 import de.neemann.digital.analyse.expression.Variable;
 import de.neemann.digital.builder.*;
+import de.neemann.digital.builder.Gal16v8.BuilderCollectorGAL;
 import de.neemann.digital.builder.jedec.FuseMap;
 import de.neemann.digital.builder.jedec.FuseMapFiller;
 import de.neemann.digital.builder.jedec.FuseMapFillerException;
@@ -36,18 +36,10 @@ public class Gal22v10JEDECExporter implements ExpressionExporter<Gal22v10JEDECEx
         map = new FuseMap(5892);
         filler = new FuseMapFiller(map, 22);
 
-        builder = new BuilderCollector() {
-            @Override
-            public BuilderCollector addCombinatorial(String name, Expression expression) throws BuilderException {
-                if (pinMap.isSimpleAlias(name, expression))
-                    return this;
-                else
-                    return super.addCombinatorial(name, expression);
-            }
-        };
         pinMap = new PinMap()
                 .setAvailInputs(2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13)
                 .setAvailOutputs(14, 15, 16, 17, 18, 19, 20, 21, 22, 23);
+        builder = new BuilderCollectorGAL(pinMap);
     }
 
     @Override

src/main/java/de/neemann/digital/builder/PinMap.java

@@ -122,14 +122,19 @@ public class PinMap {
      * Checks if the assignment is a simple A=B. If true a alias for A is generated in the pin map.
      * This is needed to void to assign two pins to the same logical signal generated by a flip flop.
      *
-     * @param name       the name of the target
+     * @param name           the name of the target
-     * @param expression the expression to check
+     * @param expression     the expression to check
+     * @param sequentialVars if a set is given, only the assignments generated from one of the
+     *                       contained variables are removed. Maybe null.
      * @return true if expression is a simple variable
      */
-    public boolean isSimpleAlias(String name, Expression expression) {
+    public boolean isSimpleAlias(String name, Expression expression, HashSet<String> sequentialVars) {
         if (expression instanceof Variable) {
             String al = ((Variable) expression).getIdentifier();
 
+            if (sequentialVars != null && !sequentialVars.contains(al))
+                return false;
+
             HashSet<String> found = null;
             for (HashSet<String> s : alias)
                 if (s.contains(name) || s.contains(al)) {

src/main/java/de/neemann/digital/gui/components/table/ExpressionListenerJK.java

@@ -57,7 +57,7 @@ public class ExpressionListenerJK implements ExpressionListener {
     }
 
     /**
-     * If the name belogs to a sequential state var, the state vars name is returned.
+     * If the name belongs to a sequential state var, the state vars name is returned.
      * Otherwise a null is returned
      *
      * @param name the name of the variable

src/test/java/de/neemann/digital/builder/Gal16v8/Gal16V8CuplExporterTest.java

@@ -5,12 +5,30 @@
  */
 package de.neemann.digital.builder.Gal16v8;
 
+import de.neemann.digital.analyse.*;
 import de.neemann.digital.analyse.expression.Constant;
 import de.neemann.digital.analyse.expression.Expression;
+import de.neemann.digital.analyse.expression.ExpressionException;
 import de.neemann.digital.analyse.expression.Variable;
+import de.neemann.digital.analyse.expression.format.FormatterException;
+import de.neemann.digital.analyse.expression.modify.ExpressionModifier;
+import de.neemann.digital.builder.PinMapException;
+import de.neemann.digital.core.BacktrackException;
+import de.neemann.digital.core.Model;
+import de.neemann.digital.core.NodeException;
+import de.neemann.digital.draw.elements.Circuit;
+import de.neemann.digital.draw.elements.PinException;
+import de.neemann.digital.draw.library.ElementLibrary;
+import de.neemann.digital.draw.library.ElementNotFoundException;
+import de.neemann.digital.draw.model.ModelCreator;
+import de.neemann.digital.draw.shapes.ShapeFactory;
+import de.neemann.digital.gui.components.table.BuilderExpressionCreator;
+import de.neemann.digital.gui.components.table.ExpressionCreator;
+import de.neemann.digital.gui.components.table.ExpressionListenerStore;
+import de.neemann.digital.integration.Resources;
 import junit.framework.TestCase;
 
-import java.io.ByteArrayOutputStream;
+import java.io.*;
 import java.util.Date;
 
 import static de.neemann.digital.analyse.expression.Not.not;
@@ -18,6 +36,7 @@ import static de.neemann.digital.analyse.expression.Operation.and;
 import static de.neemann.digital.analyse.expression.Operation.or;
 
 /**
+ * CUPL builder tests
  */
 public class Gal16V8CuplExporterTest extends TestCase {
 
@@ -133,4 +152,84 @@ public class Gal16V8CuplExporterTest extends TestCase {
         }
     }
 
+    public void testCuplWorkFlow() throws IOException, ElementNotFoundException, PinException, NodeException, AnalyseException, BacktrackException, PinMapException, ExpressionException, FormatterException {
+        String cupl = createCupl("dig/GAL/Medwedew.dig");
+
+        assertEquals("Name     test ;\r\n" +
+                "PartNo   00 ;\r\n" +
+                "Date     unknownDate ;\r\n" +
+                "Revision 01 ;\r\n" +
+                "Designer nn ;\r\n" +
+                "Company  unknown ;\r\n" +
+                "Assembly None ;\r\n" +
+                "Location unknown ;\r\n" +
+                "Device   g16v8a ;\r\n" +
+                "\r\n" +
+                "/* inputs */\r\n" +
+                "PIN 1 = CLK;\r\n" +
+                "\r\n" +
+                "/* outputs */\r\n" +
+                "PIN 15 = Q_3n;\r\n" +
+                "PIN 16 = Q_2n;\r\n" +
+                "PIN 17 = Q_1n;\r\n" +
+                "PIN 18 = Q_0n;\r\n" +
+                "\r\n" +
+                "/* sequential logic */\r\n" +
+                "Q_0n.D = !Q_0n;\r\n" +
+                "Q_1n.D = (Q_0n & !Q_1n) # (!Q_0n & Q_1n);\r\n" +
+                "Q_2n.D = (Q_0n & Q_1n & !Q_2n) # (!Q_0n & Q_2n) # (!Q_1n & Q_2n);\r\n" +
+                "Q_3n.D = (Q_0n & Q_1n & Q_2n & !Q_3n) # (!Q_0n & Q_3n) # (!Q_1n & Q_3n) # (!Q_2n & Q_3n);\r\n", cupl);
+    }
+
+    public void testCuplWorkFlowPassThrough() throws IOException, ElementNotFoundException, PinException, NodeException, AnalyseException, BacktrackException, PinMapException, ExpressionException, FormatterException {
+        String cupl = createCupl("dig/GAL/PassThrough.dig");
+
+        assertEquals("Name     test ;\r\n" +
+                "PartNo   00 ;\r\n" +
+                "Date     unknownDate ;\r\n" +
+                "Revision 01 ;\r\n" +
+                "Designer nn ;\r\n" +
+                "Company  unknown ;\r\n" +
+                "Assembly None ;\r\n" +
+                "Location unknown ;\r\n" +
+                "Device   g16v8a ;\r\n" +
+                "\r\n" +
+                "/* inputs */\r\n" +
+                "PIN 1 = CLK;\r\n" +
+                "PIN 3 = A;\r\n" +
+                "\r\n" +
+                "/* outputs */\r\n" +
+                "PIN 16 = Yn;\r\n" +
+                "PIN 15 = X;\r\n" +
+                "\r\n" +
+                "/* sequential logic */\r\n" +
+                "Yn.D = A;\r\n" +
+                "\r\n" +
+                "/* combinatorial logic */\r\n" +
+                "X = A;\r\n", cupl);
+    }
+
+
+    private String createCupl(String filename) throws IOException, PinException, NodeException, ElementNotFoundException, BacktrackException, AnalyseException, ExpressionException, FormatterException, PinMapException {
+        File f = new File(Resources.getRoot(), filename);
+        ElementLibrary library = new ElementLibrary();
+        Circuit c = Circuit.loadCircuit(f, new ShapeFactory(library));
+        Model model = new ModelCreator(c, new SubstituteLibrary(library)).createModel(false);
+        TruthTable t = new ModelAnalyser(model).analyse();
+
+        ExpressionListenerStore expressions = new ExpressionListenerStore(null);
+        new ExpressionCreator(t).create(expressions);
+
+        CuplExporter cuplExporter = new CuplExporter("nn", null);
+        cuplExporter.setProjectName("test");
+        final ModelAnalyserInfo modelAnalyzerInfo = t.getModelAnalyzerInfo();
+        if (modelAnalyzerInfo != null)
+            cuplExporter.getPinMapping().addAll(modelAnalyzerInfo.getPins());
+        new BuilderExpressionCreator(cuplExporter.getBuilder(), ExpressionModifier.IDENTITY).create(expressions);
+
+        StringWriter str = new StringWriter();
+        cuplExporter.writeTo(str);
+        return str.toString();
+    }
+
 }

src/test/java/de/neemann/digital/builder/PinMapTest.java

@@ -8,7 +8,12 @@ package de.neemann.digital.builder;
 import de.neemann.digital.analyse.expression.Variable;
 import junit.framework.TestCase;
 
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
+
 /**
+ *
  */
 public class PinMapTest extends TestCase {
 
@@ -131,7 +136,7 @@ public class PinMapTest extends TestCase {
 
     public void testAlias() throws PinMapException {
         pinMap.assignPin("A", 4);
-        assertTrue(pinMap.isSimpleAlias("B", new Variable("A")));
+        assertTrue(pinMap.isSimpleAlias("B", new Variable("A"), null));
 
         assertEquals(4, pinMap.getOutputFor("A"));
         assertEquals(4, pinMap.getOutputFor("B"));
@@ -139,14 +144,14 @@ public class PinMapTest extends TestCase {
 
     public void testAliasSwap() throws PinMapException {
         pinMap.assignPin("A", 4);
-        assertTrue(pinMap.isSimpleAlias("A", new Variable("B")));
+        assertTrue(pinMap.isSimpleAlias("A", new Variable("B"), null));
 
         assertEquals(4, pinMap.getOutputFor("A"));
         assertEquals(4, pinMap.getOutputFor("B"));
     }
 
     public void testAliasReverseOrder() throws PinMapException {
-        assertTrue(pinMap.isSimpleAlias("B", new Variable("A")));
+        assertTrue(pinMap.isSimpleAlias("B", new Variable("A"), null));
         pinMap.assignPin("A", 4);
 
         assertEquals(4, pinMap.getOutputFor("A"));
@@ -156,12 +161,27 @@ public class PinMapTest extends TestCase {
 
     public void testAliasInput() throws PinMapException {
         pinMap.assignPin("A", 2);
-        assertTrue(pinMap.isSimpleAlias("B", new Variable("A")));
+        assertTrue(pinMap.isSimpleAlias("B", new Variable("A"), null));
 
         assertEquals(2, pinMap.getInputFor("A"));
         assertEquals(2, pinMap.getInputFor("B"));
     }
 
+    public void testAliasSequential() throws PinMapException {
+        pinMap.assignPin("A", 4);
+        assertFalse(pinMap.isSimpleAlias("B", new Variable("A"), new HashSet<>()));
+
+        assertEquals(4, pinMap.getOutputFor("A"));
+        assertEquals(5, pinMap.getOutputFor("B"));
+    }
+
+    public void testAliasSequential2() throws PinMapException {
+        pinMap.assignPin("A", 4);
+        assertTrue(pinMap.isSimpleAlias("B", new Variable("A"), new HashSet<>(Collections.singletonList("A"))));
+
+        assertEquals(4, pinMap.getOutputFor("A"));
+        assertEquals(4, pinMap.getOutputFor("B"));
+    }
 
     public void testToString() throws PinMapException {
         pinMap.assignPin("A", 1);

src/test/resources/dig/GAL/Medwedew.dig

@@ -0,0 +1,864 @@
+<?xml version="1.0" encoding="utf-8"?>
+<circuit>
+  <version>1</version>
+  <attributes/>
+  <visualElements>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Inputs</string>
+          <int>1</int>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_3^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="340" y="180"/>
+    </visualElement>
+    <visualElement>
+      <elementName>D_FF</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Q_3^n</string>
+        </entry>
+        <entry>
+          <string>Inputs</string>
+          <int>1</int>
+        </entry>
+      </elementAttributes>
+      <pos x="260" y="180"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Or</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Inputs</string>
+          <int>4</int>
+        </entry>
+      </elementAttributes>
+      <pos x="140" y="140"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Inputs</string>
+          <int>4</int>
+        </entry>
+      </elementAttributes>
+      <pos x="20" y="0"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes/>
+      <pos x="20" y="120"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes/>
+      <pos x="20" y="200"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes/>
+      <pos x="20" y="280"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Inputs</string>
+          <int>1</int>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_2^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="340" y="460"/>
+    </visualElement>
+    <visualElement>
+      <elementName>D_FF</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Q_2^n</string>
+        </entry>
+        <entry>
+          <string>Inputs</string>
+          <int>1</int>
+        </entry>
+      </elementAttributes>
+      <pos x="260" y="460"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Or</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Inputs</string>
+          <int>3</int>
+        </entry>
+      </elementAttributes>
+      <pos x="120" y="440"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Inputs</string>
+          <int>3</int>
+        </entry>
+      </elementAttributes>
+      <pos x="20" y="360"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes/>
+      <pos x="20" y="440"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes/>
+      <pos x="20" y="520"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Inputs</string>
+          <int>1</int>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_1^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="340" y="660"/>
+    </visualElement>
+    <visualElement>
+      <elementName>D_FF</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Q_1^n</string>
+        </entry>
+        <entry>
+          <string>Inputs</string>
+          <int>1</int>
+        </entry>
+      </elementAttributes>
+      <pos x="260" y="660"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Or</elementName>
+      <elementAttributes/>
+      <pos x="120" y="640"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes/>
+      <pos x="20" y="600"/>
+    </visualElement>
+    <visualElement>
+      <elementName>And</elementName>
+      <elementAttributes/>
+      <pos x="20" y="680"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Inputs</string>
+          <int>1</int>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_0^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="340" y="760"/>
+    </visualElement>
+    <visualElement>
+      <elementName>D_FF</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Q_0^n</string>
+        </entry>
+        <entry>
+          <string>Inputs</string>
+          <int>1</int>
+        </entry>
+      </elementAttributes>
+      <pos x="260" y="760"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="1"/>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_3^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="-160" y="-100"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Not</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="3"/>
+        </entry>
+      </elementAttributes>
+      <pos x="-140" y="-60"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="1"/>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_2^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="-120" y="-100"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Not</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="3"/>
+        </entry>
+      </elementAttributes>
+      <pos x="-100" y="-60"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="1"/>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_1^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="-80" y="-100"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Not</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="3"/>
+        </entry>
+      </elementAttributes>
+      <pos x="-60" y="-60"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="1"/>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_0^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="-40" y="-100"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Not</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="3"/>
+        </entry>
+      </elementAttributes>
+      <pos x="-20" y="-60"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Clock</elementName>
+      <elementAttributes>
+        <entry>
+          <string>runRealTime</string>
+          <boolean>true</boolean>
+        </entry>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="3"/>
+        </entry>
+        <entry>
+          <string>Label</string>
+          <string>C</string>
+        </entry>
+        <entry>
+          <string>Frequency</string>
+          <int>2</int>
+        </entry>
+      </elementAttributes>
+      <pos x="240" y="120"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="2"/>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_3^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="680" y="0"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Out</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Q_3</string>
+        </entry>
+        <entry>
+          <string>pinNumber</string>
+          <string>15</string>
+        </entry>
+      </elementAttributes>
+      <pos x="700" y="0"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="2"/>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_2^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="680" y="40"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Out</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Q_2</string>
+        </entry>
+        <entry>
+          <string>pinNumber</string>
+          <string>16</string>
+        </entry>
+      </elementAttributes>
+      <pos x="700" y="40"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="2"/>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_1^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="680" y="80"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Out</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Q_1</string>
+        </entry>
+        <entry>
+          <string>pinNumber</string>
+          <string>17</string>
+        </entry>
+      </elementAttributes>
+      <pos x="700" y="80"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Tunnel</elementName>
+      <elementAttributes>
+        <entry>
+          <string>rotation</string>
+          <rotation rotation="2"/>
+        </entry>
+        <entry>
+          <string>NetName</string>
+          <string>Q_0^n</string>
+        </entry>
+      </elementAttributes>
+      <pos x="680" y="120"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Out</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Q_0</string>
+        </entry>
+        <entry>
+          <string>pinNumber</string>
+          <string>18</string>
+        </entry>
+      </elementAttributes>
+      <pos x="700" y="120"/>
+    </visualElement>
+  </visualElements>
+  <wires>
+    <wire>
+      <p1 x="-40" y="0"/>
+      <p2 x="20" y="0"/>
+    </wire>
+    <wire>
+      <p1 x="680" y="0"/>
+      <p2 x="700" y="0"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="320"/>
+      <p2 x="20" y="320"/>
+    </wire>
+    <wire>
+      <p1 x="-60" y="640"/>
+      <p2 x="20" y="640"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="640"/>
+      <p2 x="120" y="640"/>
+    </wire>
+    <wire>
+      <p1 x="-60" y="200"/>
+      <p2 x="20" y="200"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="200"/>
+      <p2 x="140" y="200"/>
+    </wire>
+    <wire>
+      <p1 x="240" y="200"/>
+      <p2 x="260" y="200"/>
+    </wire>
+    <wire>
+      <p1 x="-60" y="520"/>
+      <p2 x="20" y="520"/>
+    </wire>
+    <wire>
+      <p1 x="120" y="140"/>
+      <p2 x="140" y="140"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="140"/>
+      <p2 x="100" y="140"/>
+    </wire>
+    <wire>
+      <p1 x="320" y="460"/>
+      <p2 x="340" y="460"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="460"/>
+      <p2 x="120" y="460"/>
+    </wire>
+    <wire>
+      <p1 x="180" y="460"/>
+      <p2 x="260" y="460"/>
+    </wire>
+    <wire>
+      <p1 x="240" y="780"/>
+      <p2 x="260" y="780"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="-80"/>
+      <p2 x="-140" y="-80"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="-80"/>
+      <p2 x="-100" y="-80"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="-80"/>
+      <p2 x="-60" y="-80"/>
+    </wire>
+    <wire>
+      <p1 x="-40" y="-80"/>
+      <p2 x="-20" y="-80"/>
+    </wire>
+    <wire>
+      <p1 x="-140" y="80"/>
+      <p2 x="20" y="80"/>
+    </wire>
+    <wire>
+      <p1 x="680" y="80"/>
+      <p2 x="700" y="80"/>
+    </wire>
+    <wire>
+      <p1 x="-100" y="400"/>
+      <p2 x="20" y="400"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="720"/>
+      <p2 x="20" y="720"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="20"/>
+      <p2 x="20" y="20"/>
+    </wire>
+    <wire>
+      <p1 x="320" y="660"/>
+      <p2 x="340" y="660"/>
+    </wire>
+    <wire>
+      <p1 x="180" y="660"/>
+      <p2 x="260" y="660"/>
+    </wire>
+    <wire>
+      <p1 x="-100" y="280"/>
+      <p2 x="20" y="280"/>
+    </wire>
+    <wire>
+      <p1 x="-40" y="600"/>
+      <p2 x="20" y="600"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="220"/>
+      <p2 x="100" y="220"/>
+    </wire>
+    <wire>
+      <p1 x="120" y="220"/>
+      <p2 x="140" y="220"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="540"/>
+      <p2 x="100" y="540"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="160"/>
+      <p2 x="20" y="160"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="160"/>
+      <p2 x="140" y="160"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="480"/>
+      <p2 x="20" y="480"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="480"/>
+      <p2 x="120" y="480"/>
+    </wire>
+    <wire>
+      <p1 x="240" y="480"/>
+      <p2 x="260" y="480"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="40"/>
+      <p2 x="120" y="40"/>
+    </wire>
+    <wire>
+      <p1 x="680" y="40"/>
+      <p2 x="700" y="40"/>
+    </wire>
+    <wire>
+      <p1 x="-40" y="360"/>
+      <p2 x="20" y="360"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="680"/>
+      <p2 x="20" y="680"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="680"/>
+      <p2 x="120" y="680"/>
+    </wire>
+    <wire>
+      <p1 x="240" y="680"/>
+      <p2 x="260" y="680"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="300"/>
+      <p2 x="120" y="300"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="620"/>
+      <p2 x="100" y="620"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="240"/>
+      <p2 x="20" y="240"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="560"/>
+      <p2 x="20" y="560"/>
+    </wire>
+    <wire>
+      <p1 x="320" y="180"/>
+      <p2 x="340" y="180"/>
+    </wire>
+    <wire>
+      <p1 x="200" y="180"/>
+      <p2 x="260" y="180"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="120"/>
+      <p2 x="20" y="120"/>
+    </wire>
+    <wire>
+      <p1 x="680" y="120"/>
+      <p2 x="700" y="120"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="440"/>
+      <p2 x="120" y="440"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="440"/>
+      <p2 x="20" y="440"/>
+    </wire>
+    <wire>
+      <p1 x="320" y="760"/>
+      <p2 x="340" y="760"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="760"/>
+      <p2 x="260" y="760"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="60"/>
+      <p2 x="20" y="60"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="380"/>
+      <p2 x="20" y="380"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="380"/>
+      <p2 x="100" y="380"/>
+    </wire>
+    <wire>
+      <p1 x="80" y="700"/>
+      <p2 x="100" y="700"/>
+    </wire>
+    <wire>
+      <p1 x="240" y="120"/>
+      <p2 x="240" y="200"/>
+    </wire>
+    <wire>
+      <p1 x="240" y="680"/>
+      <p2 x="240" y="780"/>
+    </wire>
+    <wire>
+      <p1 x="240" y="200"/>
+      <p2 x="240" y="480"/>
+    </wire>
+    <wire>
+      <p1 x="240" y="480"/>
+      <p2 x="240" y="680"/>
+    </wire>
+    <wire>
+      <p1 x="-100" y="-80"/>
+      <p2 x="-100" y="-60"/>
+    </wire>
+    <wire>
+      <p1 x="-100" y="-20"/>
+      <p2 x="-100" y="280"/>
+    </wire>
+    <wire>
+      <p1 x="-100" y="280"/>
+      <p2 x="-100" y="400"/>
+    </wire>
+    <wire>
+      <p1 x="-100" y="400"/>
+      <p2 x="-100" y="820"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="-80"/>
+      <p2 x="-20" y="-60"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="-20"/>
+      <p2 x="-20" y="120"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="680"/>
+      <p2 x="-20" y="760"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="760"/>
+      <p2 x="-20" y="820"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="440"/>
+      <p2 x="-20" y="680"/>
+    </wire>
+    <wire>
+      <p1 x="-20" y="120"/>
+      <p2 x="-20" y="440"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="140"/>
+      <p2 x="100" y="160"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="200"/>
+      <p2 x="100" y="220"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="380"/>
+      <p2 x="100" y="440"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="480"/>
+      <p2 x="100" y="540"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="620"/>
+      <p2 x="100" y="640"/>
+    </wire>
+    <wire>
+      <p1 x="100" y="680"/>
+      <p2 x="100" y="700"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="-100"/>
+      <p2 x="-120" y="-80"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="60"/>
+      <p2 x="-120" y="480"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="560"/>
+      <p2 x="-120" y="820"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="480"/>
+      <p2 x="-120" y="560"/>
+    </wire>
+    <wire>
+      <p1 x="-120" y="-80"/>
+      <p2 x="-120" y="60"/>
+    </wire>
+    <wire>
+      <p1 x="-40" y="-100"/>
+      <p2 x="-40" y="-80"/>
+    </wire>
+    <wire>
+      <p1 x="-40" y="-80"/>
+      <p2 x="-40" y="0"/>
+    </wire>
+    <wire>
+      <p1 x="-40" y="360"/>
+      <p2 x="-40" y="600"/>
+    </wire>
+    <wire>
+      <p1 x="-40" y="600"/>
+      <p2 x="-40" y="820"/>
+    </wire>
+    <wire>
+      <p1 x="-40" y="0"/>
+      <p2 x="-40" y="360"/>
+    </wire>
+    <wire>
+      <p1 x="120" y="40"/>
+      <p2 x="120" y="140"/>
+    </wire>
+    <wire>
+      <p1 x="120" y="220"/>
+      <p2 x="120" y="300"/>
+    </wire>
+    <wire>
+      <p1 x="-140" y="-80"/>
+      <p2 x="-140" y="-60"/>
+    </wire>
+    <wire>
+      <p1 x="-140" y="-20"/>
+      <p2 x="-140" y="80"/>
+    </wire>
+    <wire>
+      <p1 x="-140" y="80"/>
+      <p2 x="-140" y="820"/>
+    </wire>
+    <wire>
+      <p1 x="-60" y="-80"/>
+      <p2 x="-60" y="-60"/>
+    </wire>
+    <wire>
+      <p1 x="-60" y="-20"/>
+      <p2 x="-60" y="200"/>
+    </wire>
+    <wire>
+      <p1 x="-60" y="520"/>
+      <p2 x="-60" y="640"/>
+    </wire>
+    <wire>
+      <p1 x="-60" y="200"/>
+      <p2 x="-60" y="520"/>
+    </wire>
+    <wire>
+      <p1 x="-60" y="640"/>
+      <p2 x="-60" y="820"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="-100"/>
+      <p2 x="-160" y="-80"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="320"/>
+      <p2 x="-160" y="820"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="240"/>
+      <p2 x="-160" y="320"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="-80"/>
+      <p2 x="-160" y="160"/>
+    </wire>
+    <wire>
+      <p1 x="-160" y="160"/>
+      <p2 x="-160" y="240"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="-100"/>
+      <p2 x="-80" y="-80"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="380"/>
+      <p2 x="-80" y="720"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="20"/>
+      <p2 x="-80" y="380"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="720"/>
+      <p2 x="-80" y="820"/>
+    </wire>
+    <wire>
+      <p1 x="-80" y="-80"/>
+      <p2 x="-80" y="20"/>
+    </wire>
+  </wires>
+  <measurementOrdering/>
+</circuit>

src/test/resources/dig/GAL/PassThrough.dig

@@ -0,0 +1,94 @@
+<?xml version="1.0" encoding="utf-8"?>
+<circuit>
+  <version>1</version>
+  <attributes/>
+  <visualElements>
+    <visualElement>
+      <elementName>D_FF</elementName>
+      <elementAttributes/>
+      <pos x="220" y="60"/>
+    </visualElement>
+    <visualElement>
+      <elementName>In</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>A</string>
+        </entry>
+        <entry>
+          <string>pinNumber</string>
+          <string>3</string>
+        </entry>
+      </elementAttributes>
+      <pos x="180" y="60"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Clock</elementName>
+      <elementAttributes/>
+      <pos x="180" y="100"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Out</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>Y</string>
+        </entry>
+        <entry>
+          <string>pinNumber</string>
+          <string>16</string>
+        </entry>
+      </elementAttributes>
+      <pos x="300" y="60"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Out</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>X</string>
+        </entry>
+        <entry>
+          <string>pinNumber</string>
+          <string>15</string>
+        </entry>
+      </elementAttributes>
+      <pos x="300" y="20"/>
+    </visualElement>
+  </visualElements>
+  <wires>
+    <wire>
+      <p1 x="200" y="80"/>
+      <p2 x="220" y="80"/>
+    </wire>
+    <wire>
+      <p1 x="180" y="100"/>
+      <p2 x="200" y="100"/>
+    </wire>
+    <wire>
+      <p1 x="200" y="20"/>
+      <p2 x="300" y="20"/>
+    </wire>
+    <wire>
+      <p1 x="180" y="60"/>
+      <p2 x="200" y="60"/>
+    </wire>
+    <wire>
+      <p1 x="280" y="60"/>
+      <p2 x="300" y="60"/>
+    </wire>
+    <wire>
+      <p1 x="200" y="60"/>
+      <p2 x="220" y="60"/>
+    </wire>
+    <wire>
+      <p1 x="200" y="80"/>
+      <p2 x="200" y="100"/>
+    </wire>
+    <wire>
+      <p1 x="200" y="20"/>
+      <p2 x="200" y="60"/>
+    </wire>
+  </wires>
+  <measurementOrdering/>
+</circuit>