diff options
Diffstat (limited to 'arduino_libs_1_0/I2C/I2C.cpp')
| -rw-r--r-- | arduino_libs_1_0/I2C/I2C.cpp | 744 |
1 files changed, 744 insertions, 0 deletions
diff --git a/arduino_libs_1_0/I2C/I2C.cpp b/arduino_libs_1_0/I2C/I2C.cpp new file mode 100644 index 0000000..ca08759 --- /dev/null +++ b/arduino_libs_1_0/I2C/I2C.cpp @@ -0,0 +1,744 @@ +/*
+ I2C.cpp - I2C library
+ Copyright (c) 2011-2012 Wayne Truchsess. All right reserved.
+ Rev 4.0 - January 14th, 2012
+ - Updated to make compatible with 8MHz clock frequency
+ Rev 3.0 - January 9th, 2012
+ - Modified library to be compatible with Arduino 1.0
+ - Changed argument type from boolean to uint8_t in pullUp(),
+ setSpeed() and receiveByte() functions for 1.0 compatability
+ - Modified return values for timeout feature to report
+ back where in the transmission the timeout occured.
+ - added function scan() to perform a bus scan to find devices
+ attached to the I2C bus. Similar to work done by Todbot
+ and Nick Gammon
+ Rev 2.0 - September 19th, 2011
+ - Added support for timeout function to prevent
+ and recover from bus lockup (thanks to PaulS
+ and CrossRoads on the Arduino forum)
+ - Changed return type for stop() from void to
+ uint8_t to handle timeOut function
+ Rev 1.0 - August 8th, 2011
+
+ This is a modified version of the Arduino Wire/TWI
+ library. Functions were rewritten to provide more functionality
+ and also the use of Repeated Start. Some I2C devices will not
+ function correctly without the use of a Repeated Start. The
+ initial version of this library only supports the Master.
+
+
+ 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.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+*/
+
+#if(ARDUINO >= 100)
+#include <Arduino.h>
+#else
+#include <WProgram.h>
+#endif
+
+#include <inttypes.h>
+#include "I2C.h"
+
+
+
+uint8_t I2C::bytesAvailable = 0;
+uint8_t I2C::bufferIndex = 0;
+uint8_t I2C::totalBytes = 0;
+uint16_t I2C::timeOutDelay = 0;
+
+I2C::I2C()
+{
+}
+
+
+////////////// Public Methods ////////////////////////////////////////
+
+
+
+void I2C::begin()
+{
+ #if defined(__AVR_ATmega168__) || defined(__AVR_ATmega8__) || defined(__AVR_ATmega328P__)
+ // activate internal pull-ups for twi
+ // as per note from atmega8 manual pg167
+ sbi(PORTC, 4);
+ sbi(PORTC, 5);
+ #else
+ // activate internal pull-ups for twi
+ // as per note from atmega128 manual pg204
+ sbi(PORTD, 0);
+ sbi(PORTD, 1);
+ #endif
+ // initialize twi prescaler and bit rate
+ cbi(TWSR, TWPS0);
+ cbi(TWSR, TWPS1);
+ TWBR = ((F_CPU / 100000) - 16) / 2;
+ // enable twi module, acks, and twi interrupt
+ TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA);
+}
+
+void I2C::end()
+{
+ TWCR = 0;
+}
+
+void I2C::timeOut(uint16_t _timeOut)
+{
+ timeOutDelay = _timeOut;
+}
+
+void I2C::setSpeed(uint8_t _fast)
+{
+ if(!_fast)
+ {
+ TWBR = ((F_CPU / 100000) - 16) / 2;
+ }
+ else
+ {
+ TWBR = ((F_CPU / 400000) - 16) / 2;
+ }
+}
+
+void I2C::pullup(uint8_t activate)
+{
+ if(activate)
+ {
+ #if defined(__AVR_ATmega168__) || defined(__AVR_ATmega8__) || defined(__AVR_ATmega328P__)
+ // activate internal pull-ups for twi
+ // as per note from atmega8 manual pg167
+ sbi(PORTC, 4);
+ sbi(PORTC, 5);
+ #else
+ // activate internal pull-ups for twi
+ // as per note from atmega128 manual pg204
+ sbi(PORTD, 0);
+ sbi(PORTD, 1);
+ #endif
+ }
+ else
+ {
+ #if defined(__AVR_ATmega168__) || defined(__AVR_ATmega8__) || defined(__AVR_ATmega328P__)
+ // deactivate internal pull-ups for twi
+ // as per note from atmega8 manual pg167
+ cbi(PORTC, 4);
+ cbi(PORTC, 5);
+ #else
+ // deactivate internal pull-ups for twi
+ // as per note from atmega128 manual pg204
+ cbi(PORTD, 0);
+ cbi(PORTD, 1);
+ #endif
+ }
+}
+
+void I2C::scan()
+{
+ timeOut(80);
+ uint8_t totalDevicesFound = 0;
+ Serial.println("Scanning for devices...please wait");
+ Serial.println();
+ for(uint8_t s = 8; s <= 0x77; s++)
+ {
+ returnStatus = 0;
+ returnStatus = start();
+ if(!returnStatus)
+ {
+ returnStatus = sendAddress(SLA_W(s));
+ }
+ if(returnStatus)
+ {
+ if(returnStatus == 1)
+ {
+ Serial.println("There is a problem with the bus, could not complete scan");
+ return;
+ }
+ }
+ else
+ {
+ Serial.print("Found device at address - ");
+ Serial.print(" 0x");
+ Serial.println(s,HEX);
+ totalDevicesFound++;
+ }
+ stop();
+ }
+ if(!totalDevicesFound){Serial.println("No devices found");}
+}
+
+
+
+
+/////////////carry over from Wire library ///////////
+
+uint8_t I2C::beginTransmission(uint8_t address)
+{
+ returnStatusWire = 0;
+ returnStatus = 0;
+ returnStatus = start();
+ returnStatusWire = returnStatus;
+ if(returnStatus){return(returnStatus);}
+ returnStatus = sendAddress(SLA_W(address));
+ returnStatusWire = returnStatus;
+ return(returnStatus);
+}
+
+uint8_t I2C::beginTransmission(int address)
+{
+ return(beginTransmission((uint8_t) address));
+}
+
+uint8_t I2C::send(uint8_t data)
+{
+ if(returnStatusWire)
+ {
+ return(returnStatusWire);
+ }
+ returnStatus = 0;
+ returnStatus = sendByte(data);
+ returnStatusWire = returnStatus;
+ return(returnStatus);
+}
+
+uint8_t I2C::send(int data)
+{
+ return(send((uint8_t) data));
+}
+
+uint8_t I2C::endTransmission()
+{
+ stop();
+ return(returnStatusWire);
+}
+
+uint8_t I2C::requestFrom(int address, int numberBytes)
+{
+ return(requestFrom((uint8_t) address, (uint8_t) numberBytes));
+}
+
+uint8_t I2C::requestFrom(uint8_t address, uint8_t numberBytes)
+{
+ returnStatus = 0;
+ returnStatus = read(address,numberBytes);
+ if(!returnStatus)
+ {
+ return(numberBytes);
+ }
+ return(0);
+}
+
+uint8_t I2C::available()
+{
+ return(bytesAvailable);
+}
+
+uint8_t I2C::receive()
+{
+ bufferIndex = totalBytes - bytesAvailable;
+ if(!bytesAvailable)
+ {
+ bufferIndex = 0;
+ return(0);
+ }
+ bytesAvailable--;
+ return(data[bufferIndex]);
+}
+
+
+/*return values for new functions that use the timeOut feature
+ will now return at what point in the transmission the timeout
+ occurred. Looking at a full communication sequence between a
+ master and slave (transmit data and then readback data) there
+ a total of 7 points in the sequence where a timeout can occur.
+ These are listed below and correspond to the returned value:
+ 1 - Waiting for successful completion of a Start bit
+ 2 - Waiting for ACK/NACK while addressing slave in transmit mode (MT)
+ 3 - Waiting for ACK/NACK while sending data to the slave
+ 4 - Waiting for successful completion of a Repeated Start
+ 5 - Waiting for ACK/NACK while addressing slave in receiver mode (MR)
+ 6 - Waiting for ACK/NACK while receiving data from the slave
+ 7 - Waiting for successful completion of the Stop bit
+
+ All possible return values:
+ 0: Function executed with no errors
+ 1 - 7: Timeout occurred, see above list
+ 8 - 0xFF See datasheet for exact meaning */
+
+
+/////////////////////////////////////////////////////
+
+uint8_t I2C::write(uint8_t address, uint8_t registerAddress)
+{
+ returnStatus = 0;
+ returnStatus = start();
+ if(returnStatus){return(returnStatus);}
+ returnStatus = sendAddress(SLA_W(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(2);}
+ return(returnStatus);
+ }
+ returnStatus = sendByte(registerAddress);
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(3);}
+ return(returnStatus);
+ }
+ returnStatus = stop();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(7);}
+ return(returnStatus);
+ }
+ return(returnStatus);
+}
+
+uint8_t I2C::write(int address, int registerAddress)
+{
+ return(write((uint8_t) address, (uint8_t) registerAddress));
+}
+
+uint8_t I2C::write(uint8_t address, uint8_t registerAddress, uint8_t data)
+{
+ returnStatus = 0;
+ returnStatus = start();
+ if(returnStatus){return(returnStatus);}
+ returnStatus = sendAddress(SLA_W(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(2);}
+ return(returnStatus);
+ }
+ returnStatus = sendByte(registerAddress);
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(3);}
+ return(returnStatus);
+ }
+ returnStatus = sendByte(data);
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(3);}
+ return(returnStatus);
+ }
+ returnStatus = stop();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(7);}
+ return(returnStatus);
+ }
+ return(returnStatus);
+}
+
+uint8_t I2C::write(int address, int registerAddress, int data)
+{
+ return(write((uint8_t) address, (uint8_t) registerAddress, (uint8_t) data));
+}
+
+uint8_t I2C::write(uint8_t address, uint8_t registerAddress, char *data)
+{
+ uint8_t bufferLength = strlen(data);
+ returnStatus = 0;
+ returnStatus = write(address, registerAddress, (uint8_t*)data, bufferLength);
+ return(returnStatus);
+}
+
+uint8_t I2C::write(uint8_t address, uint8_t registerAddress, uint8_t *data, uint8_t numberBytes)
+{
+ returnStatus = 0;
+ returnStatus = start();
+ if(returnStatus){return(returnStatus);}
+ returnStatus = sendAddress(SLA_W(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(2);}
+ return(returnStatus);
+ }
+ returnStatus = sendByte(registerAddress);
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(3);}
+ return(returnStatus);
+ }
+ for (uint8_t i = 0; i < numberBytes; i++)
+ {
+ returnStatus = sendByte(data[i]);
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(3);}
+ return(returnStatus);
+ }
+ }
+ returnStatus = stop();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(7);}
+ return(returnStatus);
+ }
+ return(returnStatus);
+}
+
+uint8_t I2C::read(int address, int numberBytes)
+{
+ return(read((uint8_t) address, (uint8_t) numberBytes));
+}
+
+uint8_t I2C::read(uint8_t address, uint8_t numberBytes)
+{
+ bytesAvailable = 0;
+ bufferIndex = 0;
+ if(numberBytes == 0){numberBytes++;}
+ nack = numberBytes - 1;
+ returnStatus = 0;
+ returnStatus = start();
+ if(returnStatus){return(returnStatus);}
+ returnStatus = sendAddress(SLA_R(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(5);}
+ return(returnStatus);
+ }
+ for(uint8_t i = 0; i < numberBytes; i++)
+ {
+ if( i == nack )
+ {
+ returnStatus = receiveByte(0);
+ if(returnStatus == 1){return(6);}
+
+ if(returnStatus != MR_DATA_NACK){return(returnStatus);}
+ }
+ else
+ {
+ returnStatus = receiveByte(1);
+ if(returnStatus == 1){return(6);}
+ if(returnStatus != MR_DATA_ACK){return(returnStatus);}
+ }
+ data[i] = TWDR;
+ bytesAvailable = i+1;
+ totalBytes = i+1;
+ }
+ returnStatus = stop();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(7);}
+ return(returnStatus);
+ }
+ return(returnStatus);
+}
+
+uint8_t I2C::read(int address, int registerAddress, int numberBytes)
+{
+ return(read((uint8_t) address, (uint8_t) registerAddress, (uint8_t) numberBytes));
+}
+
+uint8_t I2C::read(uint8_t address, uint8_t registerAddress, uint8_t numberBytes)
+{
+ bytesAvailable = 0;
+ bufferIndex = 0;
+ if(numberBytes == 0){numberBytes++;}
+ nack = numberBytes - 1;
+ returnStatus = 0;
+ returnStatus = start();
+ if(returnStatus){return(returnStatus);}
+ returnStatus = sendAddress(SLA_W(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(2);}
+ return(returnStatus);
+ }
+ returnStatus = sendByte(registerAddress);
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(3);}
+ return(returnStatus);
+ }
+ returnStatus = start();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(4);}
+ return(returnStatus);
+ }
+ returnStatus = sendAddress(SLA_R(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(5);}
+ return(returnStatus);
+ }
+ for(uint8_t i = 0; i < numberBytes; i++)
+ {
+ if( i == nack )
+ {
+ returnStatus = receiveByte(0);
+ if(returnStatus == 1){return(6);}
+ if(returnStatus != MR_DATA_NACK){return(returnStatus);}
+ }
+ else
+ {
+ returnStatus = receiveByte(1);
+ if(returnStatus == 1){return(6);}
+ if(returnStatus != MR_DATA_ACK){return(returnStatus);}
+ }
+ data[i] = TWDR;
+ bytesAvailable = i+1;
+ totalBytes = i+1;
+ }
+ returnStatus = stop();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(7);}
+ return(returnStatus);
+ }
+ return(returnStatus);
+}
+
+uint8_t I2C::read(uint8_t address, uint8_t numberBytes, uint8_t *dataBuffer)
+{
+ bytesAvailable = 0;
+ bufferIndex = 0;
+ if(numberBytes == 0){numberBytes++;}
+ nack = numberBytes - 1;
+ returnStatus = 0;
+ returnStatus = start();
+ if(returnStatus){return(returnStatus);}
+ returnStatus = sendAddress(SLA_R(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(5);}
+ return(returnStatus);
+ }
+ for(uint8_t i = 0; i < numberBytes; i++)
+ {
+ if( i == nack )
+ {
+ returnStatus = receiveByte(0);
+ if(returnStatus == 1){return(6);}
+ if(returnStatus != MR_DATA_NACK){return(returnStatus);}
+ }
+ else
+ {
+ returnStatus = receiveByte(1);
+ if(returnStatus == 1){return(6);}
+ if(returnStatus != MR_DATA_ACK){return(returnStatus);}
+ }
+ dataBuffer[i] = TWDR;
+ bytesAvailable = i+1;
+ totalBytes = i+1;
+ }
+ returnStatus = stop();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(7);}
+ return(returnStatus);
+ }
+ return(returnStatus);
+}
+
+uint8_t I2C::read(uint8_t address, uint8_t registerAddress, uint8_t numberBytes, uint8_t *dataBuffer)
+{
+ bytesAvailable = 0;
+ bufferIndex = 0;
+ if(numberBytes == 0){numberBytes++;}
+ nack = numberBytes - 1;
+ returnStatus = 0;
+ returnStatus = start();
+ if(returnStatus){return(returnStatus);}
+ returnStatus = sendAddress(SLA_W(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(2);}
+ return(returnStatus);
+ }
+ returnStatus = sendByte(registerAddress);
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(3);}
+ return(returnStatus);
+ }
+ returnStatus = start();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(4);}
+ return(returnStatus);
+ }
+ returnStatus = sendAddress(SLA_R(address));
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(5);}
+ return(returnStatus);
+ }
+ for(uint8_t i = 0; i < numberBytes; i++)
+ {
+ if( i == nack )
+ {
+ returnStatus = receiveByte(0);
+ if(returnStatus == 1){return(6);}
+ if(returnStatus != MR_DATA_NACK){return(returnStatus);}
+ }
+ else
+ {
+ returnStatus = receiveByte(1);
+ if(returnStatus == 1){return(6);}
+ if(returnStatus != MR_DATA_ACK){return(returnStatus);}
+ }
+ dataBuffer[i] = TWDR;
+ bytesAvailable = i+1;
+ totalBytes = i+1;
+ }
+ returnStatus = stop();
+ if(returnStatus)
+ {
+ if(returnStatus == 1){return(7);}
+ return(returnStatus);
+ }
+ return(returnStatus);
+}
+
+
+/////////////// Private Methods ////////////////////////////////////////
+
+
+uint8_t I2C::start()
+{
+ unsigned long startingTime = millis();
+ TWCR = (1<<TWINT)|(1<<TWSTA)|(1<<TWEN);
+ while (!(TWCR & (1<<TWINT)))
+ {
+ if(!timeOutDelay){continue;}
+ if((millis() - startingTime) >= timeOutDelay)
+ {
+ lockUp();
+ return(1);
+ }
+
+ }
+ if ((TWI_STATUS == START) || (TWI_STATUS == REPEATED_START))
+ {
+ return(0);
+ }
+ return(TWI_STATUS);
+}
+
+uint8_t I2C::sendAddress(uint8_t i2cAddress)
+{
+ TWDR = i2cAddress;
+ unsigned long startingTime = millis();
+ TWCR = (1<<TWINT) | (1<<TWEN);
+ while (!(TWCR & (1<<TWINT)))
+ {
+ if(!timeOutDelay){continue;}
+ if((millis() - startingTime) >= timeOutDelay)
+ {
+ lockUp();
+ return(1);
+ }
+
+ }
+ if ((TWI_STATUS == MT_SLA_ACK) || (TWI_STATUS == MR_SLA_ACK))
+ {
+ return(0);
+ }
+ return(TWI_STATUS);
+}
+
+uint8_t I2C::sendByte(uint8_t i2cData)
+{
+ TWDR = i2cData;
+ unsigned long startingTime = millis();
+ TWCR = (1<<TWINT) | (1<<TWEN);
+ while (!(TWCR & (1<<TWINT)))
+ {
+ if(!timeOutDelay){continue;}
+ if((millis() - startingTime) >= timeOutDelay)
+ {
+ lockUp();
+ return(1);
+ }
+
+ }
+ if (TWI_STATUS == MT_DATA_ACK)
+ {
+ return(0);
+ }
+ return(TWI_STATUS);
+}
+
+uint8_t I2C::receiveByte(uint8_t ack)
+{
+ unsigned long startingTime = millis();
+ if(ack)
+ {
+ TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
+
+ }
+ else
+ {
+ TWCR = (1<<TWINT) | (1<<TWEN);
+ }
+ while (!(TWCR & (1<<TWINT)))
+ {
+ if(!timeOutDelay){continue;}
+ if((millis() - startingTime) >= timeOutDelay)
+ {
+ lockUp();
+ return(1);
+ }
+
+ }
+ return(TWI_STATUS);
+}
+
+uint8_t I2C::stop()
+{
+ unsigned long startingTime = millis();
+ TWCR = (1<<TWINT)|(1<<TWEN)| (1<<TWSTO);
+ while ((TWCR & (1<<TWSTO)))
+ {
+ if(!timeOutDelay){continue;}
+ if((millis() - startingTime) >= timeOutDelay)
+ {
+ lockUp();
+ return(1);
+ }
+
+ }
+ return(0);
+}
+
+void I2C::lockUp()
+{
+ TWCR = 0; //releases SDA and SCL lines to high impedance
+ TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA); //reinitialize TWI
+}
+
+SIGNAL(TWI_vect)
+{
+ switch(TWI_STATUS){
+ case 0x20:
+ case 0x30:
+//break;
+ case 0x48:
+ TWCR = (1<<TWINT)|(1<<TWEN)| (1<<TWSTO); // send a stop
+ break;
+ case 0x38:
+ case 0x68:
+ case 0x78:
+ case 0xB0:
+ TWCR = 0; //releases SDA and SCL lines to high impedance
+ TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA); //reinitialize TWI
+ break;
+ }
+}
+
+
+I2C I2c = I2C();
+
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