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authorDavid A. Mellis <d.mellis@arduino.cc>2009-07-14 21:32:55 +0000
committerDavid A. Mellis <d.mellis@arduino.cc>2009-07-14 21:32:55 +0000
commit3f5220e4549900f1d1dd768ca204b34625ca9558 (patch)
treee9d4b6ea8b3c0f36b55c7e8c96c3540fb53dbe20 /libraries/Firmata/examples/I2CFirmata/I2CFirmata.pde
parent17dd73977743e4a15f968bdcf0093c58ca65196d (diff)
Updating to Firmata-2.1beta1 (rev 23).
Diffstat (limited to 'libraries/Firmata/examples/I2CFirmata/I2CFirmata.pde')
-rw-r--r--libraries/Firmata/examples/I2CFirmata/I2CFirmata.pde220
1 files changed, 220 insertions, 0 deletions
diff --git a/libraries/Firmata/examples/I2CFirmata/I2CFirmata.pde b/libraries/Firmata/examples/I2CFirmata/I2CFirmata.pde
new file mode 100644
index 0000000..ffcb589
--- /dev/null
+++ b/libraries/Firmata/examples/I2CFirmata/I2CFirmata.pde
@@ -0,0 +1,220 @@
+/*
+ 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 nextExecuteMillis; // 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.send((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.receive();
+ }
+ // 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.send(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(PC3, PC2);
+ }
+
+ 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_DIGITAL_PINS; ++i) {
+ pinMode(i, OUTPUT);
+ }
+
+ /* I2C data is not reliable at higher baud rates, you'll need to change the
+ baud rate on the host computer as well. To get a firmware running with
+ minimal effort, you can try using the default baud rate (115200) */
+ Firmata.begin(38400);
+ Wire.begin();
+}
+
+void loop()
+{
+ while (Firmata.available()) {
+ Firmata.processInput();
+ }
+
+ currentMillis = millis();
+ if (currentMillis > nextExecuteMillis) {
+ nextExecuteMillis = currentMillis + samplingInterval;
+
+ for (byte i = 0; i < queryIndex; i++) {
+ readAndReportData(query[i].addr, query[i].reg, query[i].bytes);
+ }
+ }
+}