1 files changed, 228 insertions, 0 deletions
diff --git a/libraries/Firmata/examples/I2CFirmata/I2CFirmata.ino b/libraries/Firmata/examples/I2CFirmata/I2CFirmata.ino
new file mode 100644
index 0000000..1da8963
--- /dev/null
+++ b/libraries/Firmata/examples/I2CFirmata/I2CFirmata.ino
@@ -0,0 +1,228 @@
+/*
+ * Firmata is a generic protocol for communicating with microcontrollers
+ * from software on a host computer. It is intended to work with
+ * any host computer software package.
+ *
+ * To download a host software package, please clink on the following link
+ * to open the download page in your default browser.
+ *
+ * http://firmata.org/wiki/Download
+ */
+
+/*
+ Copyright (C) 2009 Jeff Hoefs.  All rights reserved.
+ Copyright (C) 2009 Shigeru Kobayashi.  All rights reserved.
+ 
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+ 
+ See file LICENSE.txt for further informations on licensing terms.
+ */
+
+#include <Wire.h>
+#include <Firmata.h>
+
+
+#define I2C_WRITE B00000000
+#define I2C_READ B00001000
+#define I2C_READ_CONTINUOUSLY B00010000
+#define I2C_STOP_READING B00011000
+#define I2C_READ_WRITE_MODE_MASK B00011000
+
+#define MAX_QUERIES 8
+
+unsigned long currentMillis;     // store the current value from millis()
+unsigned long previousMillis;    // for comparison with currentMillis
+unsigned int samplingInterval = 32;  // default sampling interval is 33ms
+unsigned int i2cReadDelayTime = 0;  // default delay time between i2c read request and Wire.requestFrom()
+unsigned int powerPinsEnabled = 0;  // use as boolean to prevent enablePowerPins from being called more than once
+
+#define MINIMUM_SAMPLING_INTERVAL 10
+
+#define REGISTER_NOT_SPECIFIED -1
+
+struct i2c_device_info {
+  byte addr;
+  byte reg;
+  byte bytes;
+};
+
+i2c_device_info query[MAX_QUERIES];
+
+byte i2cRxData[32];
+boolean readingContinuously = false;
+byte queryIndex = 0;
+
+void readAndReportData(byte address, int theRegister, byte numBytes)
+{
+  if (theRegister != REGISTER_NOT_SPECIFIED) {
+    Wire.beginTransmission(address);
+    Wire.write((byte)theRegister);
+    Wire.endTransmission();
+    delayMicroseconds(i2cReadDelayTime);  // delay is necessary for some devices such as WiiNunchuck
+  } 
+  else {
+    theRegister = 0;  // fill the register with a dummy value
+  }
+
+  Wire.requestFrom(address, numBytes);
+
+  // check to be sure correct number of bytes were returned by slave
+  if(numBytes == Wire.available()) {
+    i2cRxData[0] = address;
+    i2cRxData[1] = theRegister;
+    for (int i = 0; i < numBytes; i++) {
+      i2cRxData[2 + i] = Wire.read();
+    }
+    // send slave address, register and received bytes
+    Firmata.sendSysex(I2C_REPLY, numBytes + 2, i2cRxData);
+  }
+  else {
+    if(numBytes > Wire.available()) {
+      Firmata.sendString("I2C Read Error: Too many bytes received");
+    } else {
+      Firmata.sendString("I2C Read Error: Too few bytes received"); 
+    }
+  }
+  
+}
+
+void sysexCallback(byte command, byte argc, byte *argv)
+{
+  byte mode;
+  byte slaveAddress;
+  byte slaveRegister;
+  byte data;
+  int  delayTime;
+
+  if (command == I2C_REQUEST) {
+    mode = argv[1] & I2C_READ_WRITE_MODE_MASK;
+    slaveAddress = argv[0];
+
+    switch(mode) {
+    case I2C_WRITE:
+      Wire.beginTransmission(slaveAddress);
+      for (byte i = 2; i < argc; i += 2) {
+        data = argv[i] + (argv[i + 1] << 7);
+        Wire.write(data);
+      }
+      Wire.endTransmission();
+      delayMicroseconds(70); // TODO is this needed?
+      break;
+    case I2C_READ:
+      if (argc == 6) {
+        // a slave register is specified
+        slaveRegister = argv[2] + (argv[3] << 7);
+        data = argv[4] + (argv[5] << 7);  // bytes to read
+        readAndReportData(slaveAddress, (int)slaveRegister, data);
+      } 
+      else {
+        // a slave register is NOT specified
+        data = argv[2] + (argv[3] << 7);  // bytes to read
+        readAndReportData(slaveAddress, (int)REGISTER_NOT_SPECIFIED, data);
+      }
+      break;
+    case I2C_READ_CONTINUOUSLY:
+      if ((queryIndex + 1) >= MAX_QUERIES) {
+        // too many queries, just ignore
+        Firmata.sendString("too many queries");
+        break;
+      }
+      query[queryIndex].addr = slaveAddress;
+      query[queryIndex].reg = argv[2] + (argv[3] << 7);
+      query[queryIndex].bytes = argv[4] + (argv[5] << 7);
+      readingContinuously = true;
+      queryIndex++;
+      break;
+    case I2C_STOP_READING:
+      readingContinuously = false;
+      queryIndex = 0;
+      break;
+    default:
+      break;
+    }
+  }
+  else if (command == SAMPLING_INTERVAL) {
+    samplingInterval = argv[0] + (argv[1] << 7);
+
+    if (samplingInterval < MINIMUM_SAMPLING_INTERVAL) {
+      samplingInterval = MINIMUM_SAMPLING_INTERVAL;
+    }
+
+    samplingInterval -= 1;
+    Firmata.sendString("sampling interval");
+  }
+
+  else if (command == I2C_CONFIG) {
+    delayTime = (argv[4] + (argv[5] << 7));                        // MSB
+    delayTime = (delayTime << 8) + (argv[2] + (argv[3] << 7));     // add LSB
+
+    if((argv[0] + (argv[1] << 7)) > 0) {
+      enablePowerPins(PORTC3, PORTC2);
+    }
+
+    if(delayTime > 0) {
+      i2cReadDelayTime = delayTime;
+    }
+
+    if(argc > 6) {
+      // If you extend I2C_Config, handle your data here
+    }
+
+  }
+}
+
+void systemResetCallback()
+{
+  readingContinuously = false;
+  queryIndex = 0;
+}
+
+/* reference: BlinkM_funcs.h by Tod E. Kurt, ThingM, http://thingm.com/ */
+// Enables Pins A2 and A3 to be used as GND and Power
+// so that I2C devices can be plugged directly
+// into Arduino header (pins A2 - A5)
+static void enablePowerPins(byte pwrpin, byte gndpin)
+{
+  if(powerPinsEnabled == 0) {
+    DDRC |= _BV(pwrpin) | _BV(gndpin);
+    PORTC &=~ _BV(gndpin);
+    PORTC |=  _BV(pwrpin);
+    powerPinsEnabled = 1;
+    Firmata.sendString("Power pins enabled");
+    delay(100);
+  }
+}
+
+void setup()
+{
+  Firmata.setFirmwareVersion(2, 0);
+
+  Firmata.attach(START_SYSEX, sysexCallback);
+  Firmata.attach(SYSTEM_RESET, systemResetCallback);
+
+  for (int i = 0; i < TOTAL_PINS; ++i) {
+    pinMode(i, OUTPUT);
+  }
+
+  Firmata.begin(57600);  
+  Wire.begin();
+}
+
+void loop()
+{
+  while (Firmata.available()) {
+    Firmata.processInput();
+  }
+
+  currentMillis = millis();
+  if (currentMillis - previousMillis > samplingInterval) {
+    previousMillis += samplingInterval;
+
+    for (byte i = 0; i < queryIndex; i++) {
+      readAndReportData(query[i].addr, query[i].reg, query[i].bytes);
+    }
+  }
+}