Squashed commit of the following:

commit 253a31d82050650345c893d43083eebe28a293e4
Author: hneemann <helmut.neemann@arcor.de>
Date:   Tue Jan 30 17:51:25 2018 +0100

    moved delay to wiring menu

commit 21cc87424340cbea36c31919179d75c09fe94a5b
Author: hneemann <helmut.neemann@arcor.de>
Date:   Tue Jan 30 17:40:52 2018 +0100

    added testcase for new variable delay

commit 2b70d72f24734960daab0bf2795cc3453725997e
Author: hneemann <helmut.neemann@arcor.de>
Date:   Sun Jan 28 19:46:49 2018 +0100

    delay gate has a configurable delay time

src/main/java/de/neemann/digital/core/element/Keys.java

@@ -52,6 +52,16 @@ public final class Keys {
             .setComboBoxValues(new Integer[]{2, 3, 4, 5})
             .setMin(2);
 
+
+    /**
+     * the delay time used by the delay component
+     */
+    public static final Key.KeyInteger DELAY_TIME
+            = new Key.KeyInteger("delayTime", 1)
+            .setComboBoxValues(new Integer[]{1, 2, 3, 4, 5})
+            .setMin(1)
+            .setMax(20);
+
     /**
      * The elements label
      */

src/main/java/de/neemann/digital/core/wiring/Delay.java

@@ -23,12 +23,15 @@ public class Delay extends Node implements Element {
      */
     public static final ElementTypeDescription DESCRIPTION = new ElementTypeDescription(Delay.class, input("in"))
             .addAttribute(Keys.ROTATE)
-            .addAttribute(Keys.BITS);
+            .addAttribute(Keys.BITS)
+            .addAttribute(Keys.DELAY_TIME);
 
     private final ObservableValue output;
     private final int bits;
+    private final int delayTime;
     private ObservableValue input;
-    private long value;
+    private long[] value;
+    private int pos;
 
     /**
      * Creates a new instance
@@ -38,16 +41,37 @@ public class Delay extends Node implements Element {
     public Delay(ElementAttributes attributes) {
         bits = attributes.get(Keys.BITS);
         output = new ObservableValue("out", bits).setPinDescription(DESCRIPTION);
+        int dt = attributes.get(Keys.DELAY_TIME);
+        if (dt < 1)
+            delayTime = 1;
+        else
+            delayTime = dt;
+
+        value = new long[delayTime];
     }
 
     @Override
     public void readInputs() throws NodeException {
-        value = input.getValue();
+        value[pos] = input.getValue();
+        pos++;
+        if (pos >= delayTime)
+            pos = 0;
     }
 
     @Override
     public void writeOutputs() throws NodeException {
-        output.setValue(value);
+        output.setValue(value[pos]);
+
+        if (delayTime > 1) {
+            boolean same = true;
+            for (int i = 1; i < delayTime; i++)
+                if (value[0] != value[i]) {
+                    same = false;
+                    break;
+                }
+            if (!same)
+                hasChanged();
+        }
     }
 
     @Override

src/main/java/de/neemann/digital/draw/library/ElementLibrary.java

@@ -100,8 +100,7 @@ public class ElementLibrary implements Iterable<ElementLibrary.ElementContainer>
                         .add(XOr.DESCRIPTION)
                         .add(XNOr.DESCRIPTION)
                         .add(Not.DESCRIPTION)
-                        .add(LookUpTable.DESCRIPTION)
+                        .add(LookUpTable.DESCRIPTION))
-                        .add(Delay.DESCRIPTION))
                 .add(new LibraryNode(Lang.get("lib_io"))
                         .add(Out.DESCRIPTION)
                         .add(Out.LEDDESCRIPTION)
@@ -125,10 +124,11 @@ public class ElementLibrary implements Iterable<ElementLibrary.ElementContainer>
                         .add(Const.DESCRIPTION)
                         .add(Tunnel.DESCRIPTION)
                         .add(Splitter.DESCRIPTION)
-                        .add(PullUp.DESCRIPTION)
-                        .add(PullDown.DESCRIPTION)
                         .add(Driver.DESCRIPTION)
-                        .add(DriverInvSel.DESCRIPTION))
+                        .add(DriverInvSel.DESCRIPTION)
+                        .add(Delay.DESCRIPTION)
+                        .add(PullUp.DESCRIPTION)
+                        .add(PullDown.DESCRIPTION))
                 .add(new LibraryNode(Lang.get("lib_mux"))
                         .add(Multiplexer.DESCRIPTION)
                         .add(Demultiplexer.DESCRIPTION)

src/main/resources/lang/lang_de.xml

@@ -107,8 +107,9 @@
         die Adresse des gewünschten Ausgabewertes fest.</string>
     <string name="elem_LookUpTable_pin_out">Gibt den Wert an der ausgewählten Adresse aus.</string>
     <string name="elem_Delay">Verzögerung</string>
-    <string name="elem_Delay_tt">Verzögert ein Signal für eine Gatterlaufzeit. In Digital haben alle Gatter die
+    <string name="elem_Delay_tt">Verzögert ein Signal für eine einstellbare Anzahl an Gatterlaufzeiten.
-        selbe Gatterlaufzeit.
+        Alle übrigen Bauteile in Digital haben genau eine Gatterlaufzeit Verzögerung.
+        Mit diesem Bauteil lassen sich damit beliebige Laufzeiten realisieren.
     </string>
     <string name="elem_Delay_pin_in">Eingang für das zu verzögernde Signal.</string>
     <string name="elem_Delay_pin_out">Das um eine Gatterlaufzeit verzögerte Eingangssignal.</string>
@@ -998,6 +999,8 @@ Sind evtl. die Namen der Variablen nicht eindeutig?</string>
     <string name="key_outputBits_tt">Die Anzahl der Ausgangsbits muss größer sein als die Anzahl der Eingangsbits.</string>
     <string name="key_textFontSize">Schriftgröße</string>
     <string name="key_textFontSize_tt">Legt die für diesen Text zu verwendende Schriftgröße fest.</string>
+    <string name="key_delayTime">Dauer</string>
+    <string name="key_delayTime_tt">Dauer der Verzögerung in Gatterlaufzeiten.</string>
 
     <string name="mod_insertWire">Leitung eingefügt.</string>
     <string name="mod_insertCopied">Aus Zwischenablage eingefügt.</string>

src/main/resources/lang/lang_en.xml

@@ -109,7 +109,9 @@
     <string name="elem_LookUpTable_pin_out">Returns the stored value at the address set via the inputs.</string>
     <string name="elem_Delay">Delay</string>
     <string name="elem_Delay_tt">Delays the signal by on propagation delay time.
-        In Digital all gates have the same propagation delay.
+        Delays a signal for an adjustable number of gate delays.
+        All other components in Digital have a gate delay of on propagation delay time.
+        This component can be used to realize any necessary propagation delay.
     </string>
     <string name="elem_Delay_pin_in">Input of the signal to be delayed.</string>
     <string name="elem_Delay_pin_out">The input signal delayed by one gate delay time.</string>
@@ -989,6 +991,9 @@ The names of the variables may not be unique.</string>
     <string name="key_outputBits_tt">The number of output bits must be greater than the number of input bits.</string>
     <string name="key_textFontSize">Font Size</string>
     <string name="key_textFontSize_tt">Sets the font size to use for this text.</string>
+    <string name="key_delayTime">Duration</string>
+    <string name="key_delayTime_tt">Delay time in units of the common gate propagation delay.</string>
+
 
     <string name="mod_insertWire">Inserted wire.</string>
     <string name="mod_insertCopied">Insert from clipboard.</string>

src/test/java/de/neemann/digital/core/basic/DelayTest.java

@@ -4,6 +4,7 @@ import de.neemann.digital.TestExecuter;
 import de.neemann.digital.core.Model;
 import de.neemann.digital.core.ObservableValue;
 import de.neemann.digital.core.element.ElementAttributes;
+import de.neemann.digital.core.element.Keys;
 import de.neemann.digital.core.wiring.Delay;
 import junit.framework.TestCase;
 
@@ -25,4 +26,35 @@ public class DelayTest extends TestCase {
         sc.check(2, 2);
         sc.check(3, 3);
     }
+
+
+    public void testDelayVar() throws Exception {
+        for (int delayTime = 0; delayTime < 5; delayTime++) {
+            ObservableValue in = new ObservableValue("in", 1);
+
+            Model model = new Model();
+            Delay delay = model.add(new Delay(new ElementAttributes().set(Keys.DELAY_TIME, delayTime)));
+            delay.setInputs(in.asList());
+            assertEquals(1, delay.getOutputs().size());
+            ObservableValue out = delay.getOutputs().get(0);
+
+            model.init();
+
+            in.setValue(0);
+            model.doStep();
+            assertEquals(0, out.getValue());
+
+            in.setValue(1);
+            for (int i = 1; i < delayTime; i++) {
+                assertTrue(model.needsUpdate());
+                model.doMicroStep(false);
+                assertEquals(0, out.getValue());
+            }
+            assertTrue(model.needsUpdate());
+            model.doMicroStep(false);
+            assertEquals(1, out.getValue());
+            assertFalse(model.needsUpdate());
+        }
+    }
+
 }