--- /dev/null
+package net.mograsim.logic.core.components;
+
+import java.util.List;
+
+import net.mograsim.logic.core.timeline.Timeline;
+import net.mograsim.logic.core.wires.Wire;
+import net.mograsim.logic.core.wires.Wire.ReadEnd;
+import net.mograsim.logic.core.wires.Wire.ReadWriteEnd;
+
+/**
+ * Models a multiplexer. Takes an arbitrary amount of input {@link Wire}s, one of which, as determined by select, is put through to the
+ * output.
+ *
+ * @author Fabian Stemmler
+ *
+ */
+public class Demux extends BasicComponent
+{
+ private final ReadEnd select, in;
+ private final ReadWriteEnd[] outputs;
+ private final int outputSize;
+ private int selected = -1;
+
+ /**
+ * Output {@link Wire}s and in must be of uniform length
+ *
+ * @param in Must be of uniform length with all outputs.
+ * @param select Indexes the output array to which the input is mapped. Must have enough bits to index all outputs.
+ * @param outputs One of these outputs receives the input signal, depending on the select bits
+ */
+ public Demux(Timeline timeline, int processTime, ReadEnd in, ReadEnd select, ReadWriteEnd... outputs)
+ {
+ super(timeline, processTime);
+ outputSize = in.length();
+
+ this.in = in;
+ this.outputs = outputs;
+ for (int i = 0; i < this.outputs.length; i++)
+ {
+ if (outputs[i].length() != outputSize)
+ throw new IllegalArgumentException("All DEMUX wire arrays must be of uniform length!");
+ this.outputs[i] = outputs[i];
+ }
+
+ this.select = select;
+ select.addObserver(this);
+
+ int maxInputs = 1 << select.length();
+ if (this.outputs.length > maxInputs)
+ throw new IllegalArgumentException("There are more outputs (" + this.outputs.length + ") to the DEMUX than supported by "
+ + select.length() + " select bits (" + maxInputs + ").");
+ in.addObserver(this);
+ }
+
+ @Override
+ public void compute()
+ {
+ int selectValue = select.hasNumericValue() ? (int) select.getUnsignedValue() : -1;
+ if (selectValue >= outputs.length)
+ selectValue = -1;
+
+ if (selected != selectValue && selected != -1)
+ outputs[selected].clearSignals();
+
+ selected = selectValue;
+
+ if (selectValue != -1)
+ outputs[selectValue].feedSignals(in.getValues());
+ }
+
+ @Override
+ public List<ReadEnd> getAllInputs()
+ {
+ return List.of(in, select);
+ }
+
+ @Override
+ public List<ReadWriteEnd> getAllOutputs()
+ {
+ return List.of(outputs);
+ }
+}