X-Git-Url: https://mograsim.net/gitweb/?a=blobdiff_plain;f=era.mi%2Fsrc%2Fnet%2Fmograsim%2Flogic%2Fcore%2Fcomponents%2FMux.java;fp=era.mi%2Fsrc%2Fnet%2Fmograsim%2Flogic%2Fcore%2Fcomponents%2FMux.java;h=bbb10f5e8db9fc5df6561b1861f4823135e4ef8e;hb=0009789a8df6b8d4562b6e1cbfa75102a7516ea8;hp=0000000000000000000000000000000000000000;hpb=a28f7aa0dab4248e99159c5a647676170cb17a4e;p=Mograsim.git

diff --git a/era.mi/src/net/mograsim/logic/core/components/Mux.java b/era.mi/src/net/mograsim/logic/core/components/Mux.java
new file mode 100644
index 00000000..bbb10f5e
--- /dev/null
+++ b/era.mi/src/net/mograsim/logic/core/components/Mux.java
@@ -0,0 +1,95 @@
+package net.mograsim.logic.core.components;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+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 Mux extends BasicComponent
+{
+	private ReadEnd select;
+	private ReadWriteEnd out;
+	private ReadEnd[] inputs;
+	private final int outputSize;
+
+	/**
+	 * Input {@link Wire}s and out must be of uniform length
+	 * 
+	 * @param out    Must be of uniform length with all inputs.
+	 * @param select Indexes the input array which is to be mapped to the output. Must have enough bits to index all inputs.
+	 * @param inputs One of these inputs is mapped to the output, depending on the select bits
+	 */
+	public Mux(Timeline timeline, int processTime, ReadWriteEnd out, ReadEnd select, ReadEnd... inputs)
+	{
+		super(timeline, processTime);
+		outputSize = out.length();
+
+		this.inputs = inputs.clone();
+		for (int i = 0; i < this.inputs.length; i++)
+		{
+			if (inputs[i].length() != outputSize)
+				throw new IllegalArgumentException("All MUX wire arrays must be of uniform length!");
+			inputs[i].addObserver(this);
+		}
+
+		this.select = select;
+		select.addObserver(this);
+
+		int maxInputs = 1 << select.length();
+		if (this.inputs.length > maxInputs)
+			throw new IllegalArgumentException("There are more inputs (" + this.inputs.length + ") to the MUX than supported by "
+					+ select.length() + " select bits (" + maxInputs + ").");
+
+		this.out = out;
+	}
+
+	public ReadEnd getOut()
+	{
+		return out;
+	}
+
+	public ReadEnd getSelect()
+	{
+		return select;
+	}
+
+	@Override
+	public void compute()
+	{
+		int selectValue;
+		if (!select.hasNumericValue() || (selectValue = (int) select.getUnsignedValue()) >= inputs.length)
+		{
+			out.clearSignals();
+			return;
+		}
+
+		ReadEnd active = inputs[selectValue];
+		out.feedSignals(active.getValues());
+	}
+
+	@Override
+	public List<ReadEnd> getAllInputs()
+	{
+		ArrayList<ReadEnd> wires = new ArrayList<ReadEnd>(Arrays.asList(inputs));
+		wires.add(select);
+		return Collections.unmodifiableList(wires);
+	}
+
+	@Override
+	public List<ReadWriteEnd> getAllOutputs()
+	{
+		return List.of(out);
+	}
+}