Add extended analog write

Author: pjs

Firmata/Firmata.h

@@ -47,7 +47,10 @@
 #define SHIFT_DATA              0x75 // a bitstream to/from a shift register
 #define I2C_REQUEST             0x76 // send an I2C read/write request
 #define I2C_REPLY               0x77 // a reply to an I2C read request
-#define I2C_CONFIG				0x78 // config I2C settings such as delay times and power pins
+#define I2C_CONFIG              0x78 // config I2C settings such as delay times and power pins
+#define EXT_ANALOG_WRITE        0x6F // analog write (PWM, Servo, etc) to any pin
+#define PIN_MODE_QUERY          0x72 // ask for current and supported pin modes
+#define PIN_MODE_RESPONSE       0x73 // reply with current and supported pin modes
 #define REPORT_FIRMWARE         0x79 // report name and version of the firmware
 #define SAMPLING_INTERVAL       0x7A // set the poll rate of the main loop
 #define SYSEX_NON_REALTIME      0x7E // MIDI Reserved for non-realtime messages

Firmata/examples/StandardFirmata/StandardFirmata.pde

@@ -247,6 +247,14 @@ void sysexCallback(byte command, byte argc, byte *argv)
     else
       Firmata.sendString("Not enough data");
     break;
+  case EXT_ANALOG_WRITE:
+    if (argc > 1) {
+      int val = argv[1];
+      if (argc > 2) val |= (argv[2] << 7);
+      if (argc > 3) val |= (argv[3] << 14);
+      analogWriteCallback(argv[0], val);
+    }
+    break;
   }
 }