Fixed Gpio and added a working OLED driver sample

OLED is based on SSD1306 and is a UG-2864HSWEG01 device, 128 x 64. The
driver holds a live copy of the ram and has a 5 x 7 character font which
you can just pass strings to. There's still more to do with graphics and
single reliable screen writes, I think noise is my issue though!

ConsoleApplication1/AD9834DDS.cs

@@ -0,0 +1,139 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using WiringPi;
+using System.Threading;
+
+namespace SPITest
+{
+    class AD9834DDS
+    {
+#region NOT FINISHED!!
+        private static byte m_ConfigRegister0;
+        private static byte m_ConfigRegister1;
+        private const Int32 OscFreq = 50000000;
+        private static double Power28 = Math.Pow(2, 28);        //2^28
+
+        public static int RunTest()
+        {
+            //Init WiringPi library
+            int result = Init.WiringPiSetup();
+
+            if (result == -1)
+            {
+                Console.WriteLine("WiringPi init failed!");
+                return result;
+            }
+
+            //Init WiringPi SPI library
+            result = SPI.wiringPiSPISetup(1, 20000000); ;
+            if (result == -1)
+            {
+                Console.WriteLine("SPI init failed!");
+                return result;
+            }
+
+            Console.WriteLine("SPI init completed, using channel 1 at 20MHz for DDS Output");
+
+            InitDDS(true, false, true, true);
+
+            SetFrequency(10000000);         //Set output to 10MHz
+
+            ReleaseReset();
+
+            return 0;
+        }
+
+        public static void SetFrequency(float Frequency)
+        {
+            //32 bits of register data
+            UInt32 FreqReg = (UInt32)((Frequency / OscFreq) * Power28);
+
+            //Clear the bytes to write, 4 bytes, 2 bytes per 14 bit write, total 28 bits plus control codes (4 bits wide)
+            byte b0 = (byte)0x0;                    //Very first byte to write, the LSB of LSB's
+            byte b1 = (byte)64;                     //MSB, we're setting the freq 0 register
+
+            byte b2 = (byte)0x0;                    //3rd byte to write
+            byte b3 = (byte)64;                     //MSB, we're setting the freq 0 register
+
+            //Now split the 32 bits up into bytes, don't forget to make sure the 2 MSB's are left alone!!!
+            //Lower 14 LSB
+            UInt32 tmp = FreqReg;
+            b0 = (byte)(tmp &= 255);
+            FreqReg = FreqReg >> 6;                 //Right shift by 6 bits,  and shift again by 2 bit
+            tmp = FreqReg;
+            byte temp = (byte)(tmp &= 255);     //copy the 8 bits
+            temp = (byte)(temp >> 2);               //Shift right by 2 bits
+            b1 |= temp;                             //OR with the second lsb byte
+
+            //Upper 14 MSB's, FreqReq will be at the right place as we shifted it down, right.
+            tmp = FreqReg;
+            b2 = (byte)(tmp &= 255);            //Copy lower 8 bits
+            tmp = FreqReg / 256 / 256;                 //Shift a 2 bytes right and loose the lower bytes
+            b3 |= (byte)tmp;                    //OR with the last byte to write
+
+            WriteWord(b0, b1);                  //10MHz from 50MHz will give 
+            WriteWord(b2, b3);
+        }
+
+        private static void ReleaseReset()
+        {
+            byte b0 = m_ConfigRegister0;
+            byte b1 = m_ConfigRegister1;
+
+            //Reset is lsb of 2nd byte ie b1
+            b1 &= 254;
+
+            //Write to the config register
+            WriteWord(b0, b1);
+        }
+
+        //Recommended are true, false, true, true for starters
+        private static void InitDDS(bool UseSineRom, bool DivideBy2, bool UseMSBNotSine, bool EnableSBO)
+        {
+            //Set Reset register high
+            byte b0 = (byte)0x0;    //Lower byte, this is shifted in first, LSB 1st with MSB trailing
+            byte b1 = (byte)0x0;    //Upper byte
+
+            //b1 is already reset so just turn on the bits we need.
+            b1 = (byte)33;          //Set to Reset and 2 consequetive writes per freq register
+
+            if (!UseSineRom)
+                b0 |= 2;
+            if (!DivideBy2)
+                b0 |= 8;
+            if (!UseMSBNotSine)
+                b0 |= 16;
+            if (EnableSBO)
+                b0 |= 32;
+
+            //Store the values for later use, bit flipping Reset for example
+            m_ConfigRegister0 = b0;
+            m_ConfigRegister1 = b1;
+
+            //Write the configuration
+            WriteWord(b0, b1);
+        }
+
+        private static void WriteWord(byte b0, byte b1)
+        {
+            //Writes the data LSB first of B0, then B1
+            byte[] buffer = new byte[2];
+
+            buffer[0] = b0;
+            buffer[1] = b1;
+
+            //a bit of unsafe fixed memory pointer action going on here, make sure the array you're pointing to is the right size!!!
+            unsafe
+            {
+                fixed (byte* p = buffer)
+                {
+                    // Do all pointer work, ie external calls within the fixed area. The gc or clr wont try to move the object in memory while we use it.
+                    SPI.wiringPiSPIDataRW(1, p, 2); //1 is SPI channel, p is byte array, 2 is number of bytes
+                }
+            }
+        }
+
+    }
+}

ConsoleApplication1/ConsoleApplication1.csproj

@@ -15,7 +15,7 @@
     <FileAlignment>512</FileAlignment>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|x86' ">
-    <PlatformTarget>x86</PlatformTarget>
+    <PlatformTarget>AnyCPU</PlatformTarget>
     <DebugSymbols>true</DebugSymbols>
     <DebugType>full</DebugType>
     <Optimize>false</Optimize>
@@ -44,7 +44,9 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="AD9834DDS.cs" />
     <Compile Include="LoopTest.cs" />
+    <Compile Include="OLEDDriver.cs" />
     <Compile Include="Program.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
   </ItemGroup>