add 12 Mhz frequency chip bitrate (#2006)

src/devices/Mcp25xxx/FrequencyAndSpeed.cs

@@ -68,6 +68,56 @@ namespace Iot.Device.Mcp25xxx
         /// </summary>
         _8MHz5KBps,
 
+        /// <summary>
+        /// 12MHz 1000kBPS
+        /// </summary>
+        _12MHz1000KBps,
+
+        /// <summary>
+        /// 12MHz 500kBPS
+        /// </summary>
+        _12MHz500KBps,
+
+        /// <summary>
+        /// 12MHz 250kBPS
+        /// </summary>
+        _12MHz250KBps,
+
+        /// <summary>
+        /// 12MHz 200kBPS
+        /// </summary>
+        _12MHz200KBps,
+
+        /// <summary>
+        /// 12MHz 125kBPS
+        /// </summary>
+        _12MHz125KBps,
+
+        /// <summary>
+        /// 12MHz 100kBPS
+        /// </summary>
+        _12MHz100KBps,
+
+        /// <summary>
+        /// 12MHz 80kBPS
+        /// </summary>
+        _12MHz80KBps,
+
+        /// <summary>
+        /// 12MHz 50kBPS
+        /// </summary>
+        _12MHz50KBps,
+
+        /// <summary>
+        /// 12MHz 40kBPS
+        /// </summary>
+        _12MHz40KBps,
+
+        /// <summary>
+        /// 12MHz 20kBPS
+        /// </summary>
+        _12MHz20KBps,
+
         /// <summary>
         /// 16MHz 1000kBPS
         /// </summary>

src/devices/Mcp25xxx/McpBitrate.cs

@@ -25,6 +25,16 @@ namespace Iot.Device.Mcp25xxx
             { FrequencyAndSpeed._8MHz20KBps, new Tuple<byte, byte, byte>(0x07, 0xBF, 0x87) },
             { FrequencyAndSpeed._8MHz10KBps, new Tuple<byte, byte, byte>(0x0F, 0xBF, 0x87) },
             { FrequencyAndSpeed._8MHz5KBps, new Tuple<byte, byte, byte>(0x1F, 0xBF, 0x87) },
+            { FrequencyAndSpeed._12MHz1000KBps, new Tuple<byte, byte, byte>(0x00, 0x88, 0x01) },
+            { FrequencyAndSpeed._12MHz500KBps, new Tuple<byte, byte, byte>(0x00, 0x9B, 0x02) },
+            { FrequencyAndSpeed._12MHz250KBps, new Tuple<byte, byte, byte>(0x00, 0xBF, 0x06) },
+            { FrequencyAndSpeed._12MHz200KBps, new Tuple<byte, byte, byte>(0x01, 0xA4, 0x03) },
+            { FrequencyAndSpeed._12MHz125KBps, new Tuple<byte, byte, byte>(0x01, 0xBF, 0x06) },
+            { FrequencyAndSpeed._12MHz100KBps, new Tuple<byte, byte, byte>(0x02, 0xB6, 0x04) },
+            { FrequencyAndSpeed._12MHz80KBps, new Tuple<byte, byte, byte>(0x04, 0xA4, 0x03) },
+            { FrequencyAndSpeed._12MHz50KBps, new Tuple<byte, byte, byte>(0x05, 0xB6, 0x04) },
+            { FrequencyAndSpeed._12MHz40KBps, new Tuple<byte, byte, byte>(0x09, 0xA4, 0x03) },
+            { FrequencyAndSpeed._12MHz20KBps, new Tuple<byte, byte, byte>(0x0C, 0xBF, 0x05) },
             { FrequencyAndSpeed._16MHz1000KBps, new Tuple<byte, byte, byte>(0x00, 0xD0, 0x82) },
             { FrequencyAndSpeed._16MHz500KBps, new Tuple<byte, byte, byte>(0x00, 0xF0, 0x86) },
             { FrequencyAndSpeed._16MHz250KBps, new Tuple<byte, byte, byte>(0x41, 0xF1, 0x85) },