From 0bd3956fdbe1841c6b655af8ccf0ba86de550388 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bernhard=20Breu=C3=9F?= <bernhard.breuss@gmail.com>
Date: Sat, 8 Oct 2016 15:26:00 +0200
Subject: [PATCH] Add synchronous serial decoder

---
 Default/DecoderSynchronousSerial.cs | 94 +++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 Default/DecoderSynchronousSerial.cs

diff --git a/Default/DecoderSynchronousSerial.cs b/Default/DecoderSynchronousSerial.cs
new file mode 100644
index 0000000..24b0c34
--- /dev/null
+++ b/Default/DecoderSynchronousSerial.cs
@@ -0,0 +1,94 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.Composition;
+using LabNation.Interfaces;
+
+namespace LabNation.Decoders
+{
+    [Export(typeof(IProcessor))]
+    public class DecoderSynchronousSerial : IDecoder
+    {
+        public DecoderDescription Description
+        {
+            get
+            {
+                return new DecoderDescription()
+                {
+                    Name = "Synchronous Serial Decoder",
+                    ShortName = "SSI",
+                    Author = "bernhardbreuss",
+                    VersionMajor = 0,
+                    VersionMinor = 1,
+                    Description = "Synchronous serial communication using a one data and one clock wire. Converts clock and data signals into byte values.",
+                    InputWaveformTypes = new Dictionary<string, Type>() 
+                    {
+                        { "CLOCK", typeof(bool)},
+                        { "DATA", typeof(bool)},
+                    },
+                    InputWaveformExpectedToggleRates = new Dictionary<string, ToggleRate>() 
+                    {
+                        { "CLOCK", ToggleRate.High},
+                        { "DATA", ToggleRate.Medium},
+                    },
+                    Parameters = new DecoderParameter[]
+                    {
+                        new DecoderParameterInts("CPHA", new int[] { 0, 1 }, "", 0, "Clock phase. Defines whether data is sampled on rising edge (0) or falling edge (1).")
+                    }
+                };
+            }
+        }
+
+        public DecoderOutput[] Process(Dictionary<string, Array> inputWaveforms, Dictionary<string, object> parameters, double samplePeriod)
+        {
+            //name input waveforms for easier usage
+            bool[] CLOCK = (bool[])inputWaveforms["CLOCK"];
+            bool[] DATA = (bool[])inputWaveforms["DATA"];
+
+            //fetch parameters
+            bool CPHA = ((int)parameters["CPHA"] == 1);
+
+            //initialize output structure
+            List<DecoderOutput> decoderOutputList = new List<DecoderOutput>();
+
+            //init counters and flags
+            int bitCounter = 7;
+            int startIndex = 0;
+            byte decodedDataByte = 0;
+
+            //brute-force decoding of incoming bits
+            for (int i = 1; i < CLOCK.Length; i++)
+            {
+                bool clockRisingEdge = CLOCK[i] && !CLOCK[i - 1];
+                bool clockFallingEdge = !CLOCK[i] && CLOCK[i - 1];                
+
+                //Decode byte
+                bool samplingEdge = (clockRisingEdge && !CPHA) || (clockFallingEdge && CPHA);
+                if (samplingEdge)
+                {
+                    //reset each new byte
+                    if (bitCounter == 7)
+                    {
+                        decodedDataByte = 0;
+                        startIndex = i;
+                    }
+
+                    //accumulate byte values
+                    decodedDataByte = (byte)((decodedDataByte << 1) + (DATA[i] ? 1 : 0));
+
+                    //at end of byte
+                    if (bitCounter == 0)
+                    {
+                        decoderOutputList.Add(new DecoderOutputValueNumeric(startIndex, i, DecoderOutputColor.Purple, decodedDataByte, "", 8));
+                        bitCounter = 7;
+                    }
+                    else
+                    {
+                        bitCounter--;
+                    }
+                }
+            }
+
+            return decoderOutputList.ToArray();
+        }
+    }
+}
\ No newline at end of file