From be2c9273c2b3a8b1918d0a9bac334153dd752540 Mon Sep 17 00:00:00 2001 From: Thibaut VIARD Date: Tue, 21 Jun 2011 00:03:22 +0200 Subject: [PATCH] Adding SAM specific libraries --- hardware/sam/libraries/SPI/SPI.cpp | 61 +++ hardware/sam/libraries/SPI/SPI.h | 70 +++ .../BarometricPressureSensor.pde | 143 ++++++ .../BarometricPressureSensor.pde | 143 ++++++ .../DigitalPotControl/DigitalPotControl.pde | 71 +++ hardware/sam/libraries/SPI/keywords.txt | 36 ++ hardware/sam/libraries/Wire/Wire.cpp | 270 ++++++++++ hardware/sam/libraries/Wire/Wire.h | 69 +++ .../SFRRanger_reader/SFRRanger_reader.pde | 87 ++++ .../digital_potentiometer.pde | 39 ++ .../examples/master_reader/master_reader.pde | 32 ++ .../examples/master_writer/master_writer.pde | 31 ++ .../slave_receiver/slave_receiver.pde | 38 ++ .../examples/slave_sender/slave_sender.pde | 32 ++ hardware/sam/libraries/Wire/keywords.txt | 31 ++ hardware/sam/libraries/Wire/utility/twi.c | 476 ++++++++++++++++++ hardware/sam/libraries/Wire/utility/twi.h | 53 ++ 17 files changed, 1682 insertions(+) create mode 100644 hardware/sam/libraries/SPI/SPI.cpp create mode 100644 hardware/sam/libraries/SPI/SPI.h create mode 100644 hardware/sam/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.pde create mode 100644 hardware/sam/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor/BarometricPressureSensor.pde create mode 100644 hardware/sam/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.pde create mode 100644 hardware/sam/libraries/SPI/keywords.txt create mode 100644 hardware/sam/libraries/Wire/Wire.cpp create mode 100644 hardware/sam/libraries/Wire/Wire.h create mode 100644 hardware/sam/libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.pde create mode 100644 hardware/sam/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.pde create mode 100644 hardware/sam/libraries/Wire/examples/master_reader/master_reader.pde create mode 100644 hardware/sam/libraries/Wire/examples/master_writer/master_writer.pde create mode 100644 hardware/sam/libraries/Wire/examples/slave_receiver/slave_receiver.pde create mode 100644 hardware/sam/libraries/Wire/examples/slave_sender/slave_sender.pde create mode 100644 hardware/sam/libraries/Wire/keywords.txt create mode 100644 hardware/sam/libraries/Wire/utility/twi.c create mode 100644 hardware/sam/libraries/Wire/utility/twi.h diff --git a/hardware/sam/libraries/SPI/SPI.cpp b/hardware/sam/libraries/SPI/SPI.cpp new file mode 100644 index 000000000..42915df1e --- /dev/null +++ b/hardware/sam/libraries/SPI/SPI.cpp @@ -0,0 +1,61 @@ +/* + * Copyright (c) 2010 by Cristian Maglie + * SPI Master library for arduino. + * + * This file is free software; you can redistribute it and/or modify + * it under the terms of either the GNU General Public License version 2 + * or the GNU Lesser General Public License version 2.1, both as + * published by the Free Software Foundation. + */ + +#include "pins_arduino.h" +#include "SPI.h" + +SPIClass SPI; + +void SPIClass::begin() { + // Set direction register for SCK and MOSI pin. + // MISO pin automatically overrides to INPUT. + // When the SS pin is set as OUTPUT, it can be used as + // a general purpose output port (it doesn't influence + // SPI operations). + + pinMode(SCK, OUTPUT); + pinMode(MOSI, OUTPUT); + pinMode(SS, OUTPUT); + + digitalWrite(SCK, LOW); + digitalWrite(MOSI, LOW); + digitalWrite(SS, HIGH); + + // Warning: if the SS pin ever becomes a LOW INPUT then SPI + // automatically switches to Slave, so the data direction of + // the SS pin MUST be kept as OUTPUT. + SPCR |= _BV(MSTR); + SPCR |= _BV(SPE); +} + +void SPIClass::end() { + SPCR &= ~_BV(SPE); +} + +void SPIClass::setBitOrder(uint8_t bitOrder) +{ + if(bitOrder == LSBFIRST) { + SPCR |= _BV(DORD); + } else { + SPCR &= ~(_BV(DORD)); + } +} + +void SPIClass::setDataMode(uint8_t mode) +{ + SPCR = (SPCR & ~SPI_MODE_MASK) | mode; +} + +void SPIClass::setClockDivider(uint8_t rate) +{ + SPCR = (SPCR & ~SPI_CLOCK_MASK) | (rate & SPI_CLOCK_MASK); + SPSR = (SPSR & ~SPI_2XCLOCK_MASK) | ((rate >> 2) & SPI_2XCLOCK_MASK); +} + diff --git a/hardware/sam/libraries/SPI/SPI.h b/hardware/sam/libraries/SPI/SPI.h new file mode 100644 index 000000000..79c89d4d6 --- /dev/null +++ b/hardware/sam/libraries/SPI/SPI.h @@ -0,0 +1,70 @@ +/* + * Copyright (c) 2010 by Cristian Maglie + * SPI Master library for arduino. + * + * This file is free software; you can redistribute it and/or modify + * it under the terms of either the GNU General Public License version 2 + * or the GNU Lesser General Public License version 2.1, both as + * published by the Free Software Foundation. + */ + +#ifndef _SPI_H_INCLUDED +#define _SPI_H_INCLUDED + +#include +#include +#include + +#define SPI_CLOCK_DIV4 0x00 +#define SPI_CLOCK_DIV16 0x01 +#define SPI_CLOCK_DIV64 0x02 +#define SPI_CLOCK_DIV128 0x03 +#define SPI_CLOCK_DIV2 0x04 +#define SPI_CLOCK_DIV8 0x05 +#define SPI_CLOCK_DIV32 0x06 +#define SPI_CLOCK_DIV64 0x07 + +#define SPI_MODE0 0x00 +#define SPI_MODE1 0x04 +#define SPI_MODE2 0x08 +#define SPI_MODE3 0x0C + +#define SPI_MODE_MASK 0x0C // CPOL = bit 3, CPHA = bit 2 on SPCR +#define SPI_CLOCK_MASK 0x03 // SPR1 = bit 1, SPR0 = bit 0 on SPCR +#define SPI_2XCLOCK_MASK 0x01 // SPI2X = bit 0 on SPSR + +class SPIClass { +public: + inline static byte transfer(byte _data); + + // SPI Configuration methods + + inline static void attachInterrupt(); + inline static void detachInterrupt(); // Default + + static void begin(); // Default + static void end(); + + static void setBitOrder(uint8_t); + static void setDataMode(uint8_t); + static void setClockDivider(uint8_t); +}; + +extern SPIClass SPI; + +byte SPIClass::transfer(byte _data) { + SPDR = _data; + while (!(SPSR & _BV(SPIF))) + ; + return SPDR; +} + +void SPIClass::attachInterrupt() { + SPCR |= _BV(SPIE); +} + +void SPIClass::detachInterrupt() { + SPCR &= ~_BV(SPIE); +} + +#endif diff --git a/hardware/sam/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.pde b/hardware/sam/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.pde new file mode 100644 index 000000000..9d77a4261 --- /dev/null +++ b/hardware/sam/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.pde @@ -0,0 +1,143 @@ +/* + SCP1000 Barometric Pressure Sensor Display + + Shows the output of a Barometric Pressure Sensor on a + Uses the SPI library. For details on the sensor, see: + http://www.sparkfun.com/commerce/product_info.php?products_id=8161 + http://www.vti.fi/en/support/obsolete_products/pressure_sensors/ + + This sketch adapted from Nathan Seidle's SCP1000 example for PIC: + http://www.sparkfun.com/datasheets/Sensors/SCP1000-Testing.zip + + Circuit: + SCP1000 sensor attached to pins 6, 7, 10 - 13: + DRDY: pin 6 + CSB: pin 7 + MOSI: pin 11 + MISO: pin 12 + SCK: pin 13 + + created 31 July 2010 + modified 14 August 2010 + by Tom Igoe + */ + +// the sensor communicates using SPI, so include the library: +#include + +//Sensor's memory register addresses: +const int PRESSURE = 0x1F; //3 most significant bits of pressure +const int PRESSURE_LSB = 0x20; //16 least significant bits of pressure +const int TEMPERATURE = 0x21; //16 bit temperature reading +const byte READ = 0b11111100; // SCP1000's read command +const byte WRITE = 0b00000010; // SCP1000's write command + +// pins used for the connection with the sensor +// the other you need are controlled by the SPI library): +const int dataReadyPin = 6; +const int chipSelectPin = 7; + +void setup() { + Serial.begin(9600); + + // start the SPI library: + SPI.begin(); + + // initalize the data ready and chip select pins: + pinMode(dataReadyPin, INPUT); + pinMode(chipSelectPin, OUTPUT); + + //Configure SCP1000 for low noise configuration: + writeRegister(0x02, 0x2D); + writeRegister(0x01, 0x03); + writeRegister(0x03, 0x02); + // give the sensor time to set up: + delay(100); +} + +void loop() { + //Select High Resolution Mode + writeRegister(0x03, 0x0A); + + // don't do anything until the data ready pin is high: + if (digitalRead(dataReadyPin) == HIGH) { + //Read the temperature data + int tempData = readRegister(0x21, 2); + + // convert the temperature to celsius and display it: + float realTemp = (float)tempData / 20.0; + Serial.print("Temp[C]="); + Serial.print(realTemp); + + + //Read the pressure data highest 3 bits: + byte pressure_data_high = readRegister(0x1F, 1); + pressure_data_high &= 0b00000111; //you only needs bits 2 to 0 + + //Read the pressure data lower 16 bits: + unsigned int pressure_data_low = readRegister(0x20, 2); + //combine the two parts into one 19-bit number: + long pressure = ((pressure_data_high << 16) | pressure_data_low)/4; + + // display the temperature: + Serial.println("\tPressure [Pa]=" + String(pressure)); + } +} + +//Read from or write to register from the SCP1000: +unsigned int readRegister(byte thisRegister, int bytesToRead ) { + byte inByte = 0; // incoming byte from the SPI + unsigned int result = 0; // result to return + Serial.print(thisRegister, BIN); + Serial.print("\t"); + // SCP1000 expects the register name in the upper 6 bits + // of the byte. So shift the bits left by two bits: + thisRegister = thisRegister << 2; + // now combine the address and the command into one byte + byte dataToSend = thisRegister & READ; + Serial.println(thisRegister, BIN); + // take the chip select low to select the device: + digitalWrite(chipSelectPin, LOW); + // send the device the register you want to read: + SPI.transfer(dataToSend); + // send a value of 0 to read the first byte returned: + result = SPI.transfer(0x00); + // decrement the number of bytes left to read: + bytesToRead--; + // if you still have another byte to read: + if (bytesToRead > 0) { + // shift the first byte left, then get the second byte: + result = result << 8; + inByte = SPI.transfer(0x00); + // combine the byte you just got with the previous one: + result = result | inByte; + // decrement the number of bytes left to read: + bytesToRead--; + } + // take the chip select high to de-select: + digitalWrite(chipSelectPin, HIGH); + // return the result: + return(result); +} + + +//Sends a write command to SCP1000 + +void writeRegister(byte thisRegister, byte thisValue) { + + // SCP1000 expects the register address in the upper 6 bits + // of the byte. So shift the bits left by two bits: + thisRegister = thisRegister << 2; + // now combine the register address and the command into one byte: + byte dataToSend = thisRegister | WRITE; + + // take the chip select low to select the device: + digitalWrite(chipSelectPin, LOW); + + SPI.transfer(dataToSend); //Send register location + SPI.transfer(thisValue); //Send value to record into register + + // take the chip select high to de-select: + digitalWrite(chipSelectPin, HIGH); +} + diff --git a/hardware/sam/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor/BarometricPressureSensor.pde b/hardware/sam/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor/BarometricPressureSensor.pde new file mode 100644 index 000000000..9c9c9b6c8 --- /dev/null +++ b/hardware/sam/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor/BarometricPressureSensor.pde @@ -0,0 +1,143 @@ +/* + SCP1000 Barometric Pressure Sensor Display + + Shows the output of a Barometric Pressure Sensor on a + Uses the SPI library. For details on the sensor, see: + http://www.sparkfun.com/commerce/product_info.php?products_id=8161 + http://www.vti.fi/en/support/obsolete_products/pressure_sensors/ + + This sketch adapted from Nathan Seidle's SCP1000 example for PIC: + http://www.sparkfun.com/datasheets/Sensors/SCP1000-Testing.zip + + Circuit: + SCP1000 sensor attached to pins 6, 7, 10 - 13: + DRDY: pin 6 + CSB: pin 7 + MOSI: pin 11 + MISO: pin 12 + SCK: pin 13 + + created 31 July 2010 + modified 14 August 2010 + by Tom Igoe + */ + +// the sensor communicates using SPI, so include the library: +#include + +//Sensor's memory register addresses: +const int PRESSURE = 0x1F; //3 most significant bits of pressure +const int PRESSURE_LSB = 0x20; //16 least significant bits of pressure +const int TEMPERATURE = 0x21; //16 bit temperature reading +cont byte READ = 0b00000000; // SCP1000's read command +const byte WRITE = 0b00000010; // SCP1000's write command +// pins used for the connection with the sensor +// the other you need are controlled by the SPI library): +const int dataReadyPin = 6; +const int chipSelectPin = 7; + +void setup() { + Serial.begin(9600); + + // start the SPI library: + SPI.begin(); + + // initalize the data ready and chip select pins: + pinMode(dataReadyPin, INPUT); + pinMode(chipSelectPin, OUTPUT); + + //Configure SCP1000 for low noise configuration: + writeRegister(0x02, 0x2D); + writeRegister(0x01, 0x03); + writeRegister(0x03, 0x02); + // give the sensor time to set up: + delay(100); +} + +void loop() { + //Select High Resolution Mode + writeRegister(0x03, 0x0A); + + // don't do anything until the data ready pin is high: + if (digitalRead(dataReadyPin) == HIGH) { + //Read the temperature data + int tempData = readRegister(0x21, 2); + + // convert the temperature to celsius and display it: + float realTemp = (float)tempData / 20.0; + Serial.print("Temp[C]="); + Serial.print(realTemp); + + + //Read the pressure data highest 3 bits: + byte pressure_data_high = readRegister(0x1F, 1); + pressure_data_high &= 0b00000111; //you only needs bits 2 to 0 + + //Read the pressure data lower 16 bits: + unsigned int pressure_data_low = readRegister(0x20, 2); + //combine the two parts into one 19-bit number: + long pressure = ((pressure_data_high << 16) | pressure_data_low)/4; + + // display the temperature: + Serial.println("\tPressure [Pa]=" + String(pressure)); + } +} + +//Read from or write to register from the SCP1000: +unsigned int readRegister(byte thisRegister, int bytesToRead ) { + byte inByte = 0; // incoming byte from the SPI + unsigned int result = 0; // result to return + + // SCP1000 expects the register name in the upper 6 bits + // of the byte. So shift the bits left by two bits: + thisRegister = thisRegister << 2; + // now combine the address and the command into one byte + dataToSend = thisRegister & READ; + + // take the chip select low to select the device: + digitalWrite(chipSelectPin, LOW); + // send the device the register you want to read: + SPI.transfer(dataToSend); + // send a value of 0 to read the first byte returned: + result = SPI.transfer(0x00); + // decrement the number of bytes left to read: + bytesToRead--; + // if you still have another byte to read: + if (bytesToRead > 0) { + // shift the first byte left, then get the second byte: + result = result << 8; + inByte = SPI.transfer(0x00); + // combine the byte you just got with the previous one: + result = result | inByte; + // decrement the number of bytes left to read: + bytesToRead--; + } + // take the chip select high to de-select: + digitalWrite(chipSelectPin, HIGH); + // return the result: + return(result); +} + + +//Sends a write command to SCP1000 + +void writeRegister(byte thisRegister, byte thisValue) { + + // SCP1000 expects the register address in the upper 6 bits + // of the byte. So shift the bits left by two bits: + thisRegister = thisRegister << 2; + // now combine the register address and the command into one byte: + dataToSend = thisRegister | WRITE; + + // take the chip select low to select the device: + digitalWrite(chipSelectPin, LOW); + + SPI.transfer(dataToSend); //Send register location + SPI.transfer(thisValue); //Send value to record into register + + // take the chip select high to de-select: + digitalWrite(chipSelectPin, HIGH); +} + + + diff --git a/hardware/sam/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.pde b/hardware/sam/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.pde new file mode 100644 index 000000000..ef97dae88 --- /dev/null +++ b/hardware/sam/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.pde @@ -0,0 +1,71 @@ +/* + Digital Pot Control + + This example controls an Analog Devices AD5206 digital potentiometer. + The AD5206 has 6 potentiometer channels. Each channel's pins are labeled + A - connect this to voltage + W - this is the pot's wiper, which changes when you set it + B - connect this to ground. + + The AD5206 is SPI-compatible,and to command it, you send two bytes, + one with the channel number (0 - 5) and one with the resistance value for the + channel (0 - 255). + + The circuit: + * All A pins of AD5206 connected to +5V + * All B pins of AD5206 connected to ground + * An LED and a 220-ohm resisor in series connected from each W pin to ground + * CS - to digital pin 10 (SS pin) + * SDI - to digital pin 11 (MOSI pin) + * CLK - to digital pin 13 (SCK pin) + + created 10 Aug 2010 + by Tom Igoe + + Thanks to Heather Dewey-Hagborg for the original tutorial, 2005 + +*/ + + +// inslude the SPI library: +#include + + +// set pin 10 as the slave select for the digital pot: +const int slaveSelectPin = 10; + +void setup() { + // set the slaveSelectPin as an output: + pinMode (slaveSelectPin, OUTPUT); + // initialize SPI: + SPI.begin(); +} + +void loop() { + // go through the six channels of the digital pot: + for (int channel = 0; channel < 6; channel++) { + // change the resistance on this channel from min to max: + for (int level = 0; level < 255; level++) { + digitalPotWrite(channel, level); + delay(10); + } + // wait a second at the top: + delay(100); + // change the resistance on this channel from max to min: + for (int level = 0; level < 255; level++) { + digitalPotWrite(channel, 255 - level); + delay(10); + } + } + +} + +int digitalPotWrite(int address, int value) { + // take the SS pin low to select the chip: + digitalWrite(slaveSelectPin,LOW); + // send in the address and value via SPI: + SPI.transfer(address); + SPI.transfer(value); + // take the SS pin high to de-select the chip: + digitalWrite(slaveSelectPin,HIGH); +} \ No newline at end of file diff --git a/hardware/sam/libraries/SPI/keywords.txt b/hardware/sam/libraries/SPI/keywords.txt new file mode 100644 index 000000000..fa7616581 --- /dev/null +++ b/hardware/sam/libraries/SPI/keywords.txt @@ -0,0 +1,36 @@ +####################################### +# Syntax Coloring Map SPI +####################################### + +####################################### +# Datatypes (KEYWORD1) +####################################### + +SPI KEYWORD1 + +####################################### +# Methods and Functions (KEYWORD2) +####################################### +begin KEYWORD2 +end KEYWORD2 +transfer KEYWORD2 +setBitOrder KEYWORD2 +setDataMode KEYWORD2 +setClockDivider KEYWORD2 + + +####################################### +# Constants (LITERAL1) +####################################### +SPI_CLOCK_DIV4 LITERAL1 +SPI_CLOCK_DIV16 LITERAL1 +SPI_CLOCK_DIV64 LITERAL1 +SPI_CLOCK_DIV128 LITERAL1 +SPI_CLOCK_DIV2 LITERAL1 +SPI_CLOCK_DIV8 LITERAL1 +SPI_CLOCK_DIV32 LITERAL1 +SPI_CLOCK_DIV64 LITERAL1 +SPI_MODE0 LITERAL1 +SPI_MODE1 LITERAL1 +SPI_MODE2 LITERAL1 +SPI_MODE3 LITERAL1 \ No newline at end of file diff --git a/hardware/sam/libraries/Wire/Wire.cpp b/hardware/sam/libraries/Wire/Wire.cpp new file mode 100644 index 000000000..5818beef1 --- /dev/null +++ b/hardware/sam/libraries/Wire/Wire.cpp @@ -0,0 +1,270 @@ +/* + TwoWire.cpp - TWI/I2C library for Wiring & Arduino + Copyright (c) 2006 Nicholas Zambetti. All right 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. + + 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 +*/ + +extern "C" { + #include + #include + #include + #include "twi.h" +} + +#include "Wire.h" + +// Initialize Class Variables ////////////////////////////////////////////////// + +uint8_t TwoWire::rxBuffer[BUFFER_LENGTH]; +uint8_t TwoWire::rxBufferIndex = 0; +uint8_t TwoWire::rxBufferLength = 0; + +uint8_t TwoWire::txAddress = 0; +uint8_t TwoWire::txBuffer[BUFFER_LENGTH]; +uint8_t TwoWire::txBufferIndex = 0; +uint8_t TwoWire::txBufferLength = 0; + +uint8_t TwoWire::transmitting = 0; +void (*TwoWire::user_onRequest)(void); +void (*TwoWire::user_onReceive)(int); + +// Constructors //////////////////////////////////////////////////////////////// + +TwoWire::TwoWire() +{ +} + +// Public Methods ////////////////////////////////////////////////////////////// + +void TwoWire::begin(void) +{ + rxBufferIndex = 0; + rxBufferLength = 0; + + txBufferIndex = 0; + txBufferLength = 0; + + twi_init(); +} + +void TwoWire::begin(uint8_t address) +{ + twi_setAddress(address); + twi_attachSlaveTxEvent(onRequestService); + twi_attachSlaveRxEvent(onReceiveService); + begin(); +} + +void TwoWire::begin(int address) +{ + begin((uint8_t)address); +} + +uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity) +{ + // clamp to buffer length + if(quantity > BUFFER_LENGTH){ + quantity = BUFFER_LENGTH; + } + // perform blocking read into buffer + uint8_t read = twi_readFrom(address, rxBuffer, quantity); + // set rx buffer iterator vars + rxBufferIndex = 0; + rxBufferLength = read; + + return read; +} + +uint8_t TwoWire::requestFrom(int address, int quantity) +{ + return requestFrom((uint8_t)address, (uint8_t)quantity); +} + +void TwoWire::beginTransmission(uint8_t address) +{ + // indicate that we are transmitting + transmitting = 1; + // set address of targeted slave + txAddress = address; + // reset tx buffer iterator vars + txBufferIndex = 0; + txBufferLength = 0; +} + +void TwoWire::beginTransmission(int address) +{ + beginTransmission((uint8_t)address); +} + +uint8_t TwoWire::endTransmission(void) +{ + // transmit buffer (blocking) + int8_t ret = twi_writeTo(txAddress, txBuffer, txBufferLength, 1); + // reset tx buffer iterator vars + txBufferIndex = 0; + txBufferLength = 0; + // indicate that we are done transmitting + transmitting = 0; + return ret; +} + +// must be called in: +// slave tx event callback +// or after beginTransmission(address) +void TwoWire::write(uint8_t data) +{ + if(transmitting){ + // in master transmitter mode + // don't bother if buffer is full + if(txBufferLength >= BUFFER_LENGTH){ + return; + } + // put byte in tx buffer + txBuffer[txBufferIndex] = data; + ++txBufferIndex; + // update amount in buffer + txBufferLength = txBufferIndex; + }else{ + // in slave send mode + // reply to master + twi_transmit(&data, 1); + } +} + +// must be called in: +// slave tx event callback +// or after beginTransmission(address) +void TwoWire::write(const uint8_t *data, size_t quantity) +{ + if(transmitting){ + // in master transmitter mode + for(size_t i = 0; i < quantity; ++i){ + write(data[i]); + } + }else{ + // in slave send mode + // reply to master + twi_transmit(data, quantity); + } +} + +// must be called in: +// slave tx event callback +// or after beginTransmission(address) +void TwoWire::write(const char *data) +{ + write((uint8_t*)data, strlen(data)); +} + +// must be called in: +// slave rx event callback +// or after requestFrom(address, numBytes) +int TwoWire::available(void) +{ + return rxBufferLength - rxBufferIndex; +} + +// must be called in: +// slave rx event callback +// or after requestFrom(address, numBytes) +int TwoWire::read(void) +{ + int value = -1; + + // get each successive byte on each call + if(rxBufferIndex < rxBufferLength){ + value = rxBuffer[rxBufferIndex]; + ++rxBufferIndex; + } + + return value; +} + +// must be called in: +// slave rx event callback +// or after requestFrom(address, numBytes) +int TwoWire::peek(void) +{ + int value = -1; + + if(rxBufferIndex < rxBufferLength){ + value = rxBuffer[rxBufferIndex]; + } + + return value; +} + +void TwoWire::flush(void) +{ + // XXX: to be implemented. +} + +// behind the scenes function that is called when data is received +void TwoWire::onReceiveService(uint8_t* inBytes, int numBytes) +{ + // don't bother if user hasn't registered a callback + if(!user_onReceive){ + return; + } + // don't bother if rx buffer is in use by a master requestFrom() op + // i know this drops data, but it allows for slight stupidity + // meaning, they may not have read all the master requestFrom() data yet + if(rxBufferIndex < rxBufferLength){ + return; + } + // copy twi rx buffer into local read buffer + // this enables new reads to happen in parallel + for(uint8_t i = 0; i < numBytes; ++i){ + rxBuffer[i] = inBytes[i]; + } + // set rx iterator vars + rxBufferIndex = 0; + rxBufferLength = numBytes; + // alert user program + user_onReceive(numBytes); +} + +// behind the scenes function that is called when data is requested +void TwoWire::onRequestService(void) +{ + // don't bother if user hasn't registered a callback + if(!user_onRequest){ + return; + } + // reset tx buffer iterator vars + // !!! this will kill any pending pre-master sendTo() activity + txBufferIndex = 0; + txBufferLength = 0; + // alert user program + user_onRequest(); +} + +// sets function called on slave write +void TwoWire::onReceive( void (*function)(int) ) +{ + user_onReceive = function; +} + +// sets function called on slave read +void TwoWire::onRequest( void (*function)(void) ) +{ + user_onRequest = function; +} + +// Preinstantiate Objects ////////////////////////////////////////////////////// + +TwoWire Wire = TwoWire(); + diff --git a/hardware/sam/libraries/Wire/Wire.h b/hardware/sam/libraries/Wire/Wire.h new file mode 100644 index 000000000..51df04e97 --- /dev/null +++ b/hardware/sam/libraries/Wire/Wire.h @@ -0,0 +1,69 @@ +/* + TwoWire.h - TWI/I2C library for Arduino & Wiring + Copyright (c) 2006 Nicholas Zambetti. All right 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. + + 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 +*/ + +#ifndef TwoWire_h +#define TwoWire_h + +#include +#include "Stream.h" + +#define BUFFER_LENGTH 32 + +class TwoWire : public Stream +{ + private: + static uint8_t rxBuffer[]; + static uint8_t rxBufferIndex; + static uint8_t rxBufferLength; + + static uint8_t txAddress; + static uint8_t txBuffer[]; + static uint8_t txBufferIndex; + static uint8_t txBufferLength; + + static uint8_t transmitting; + static void (*user_onRequest)(void); + static void (*user_onReceive)(int); + static void onRequestService(void); + static void onReceiveService(uint8_t*, int); + public: + TwoWire(); + void begin(); + void begin(uint8_t); + void begin(int); + void beginTransmission(uint8_t); + void beginTransmission(int); + uint8_t endTransmission(void); + uint8_t requestFrom(uint8_t, uint8_t); + uint8_t requestFrom(int, int); + virtual void write(uint8_t); + virtual void write(const char *); + virtual void write(const uint8_t *, size_t); + virtual int available(void); + virtual int read(void); + virtual int peek(void); + virtual void flush(void); + void onReceive( void (*)(int) ); + void onRequest( void (*)(void) ); +}; + +extern TwoWire Wire; + +#endif + diff --git a/hardware/sam/libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.pde b/hardware/sam/libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.pde new file mode 100644 index 000000000..9c41c18f1 --- /dev/null +++ b/hardware/sam/libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.pde @@ -0,0 +1,87 @@ +// I2C SRF10 or SRF08 Devantech Ultrasonic Ranger Finder +// by Nicholas Zambetti +// and James Tichenor + +// Demonstrates use of the Wire library reading data from the +// Devantech Utrasonic Rangers SFR08 and SFR10 + +// Created 29 April 2006 + +// This example code is in the public domain. + + +#include + +void setup() +{ + Wire.begin(); // join i2c bus (address optional for master) + Serial.begin(9600); // start serial communication at 9600bps +} + +int reading = 0; + +void loop() +{ + // step 1: instruct sensor to read echoes + Wire.beginTransmission(112); // transmit to device #112 (0x70) + // the address specified in the datasheet is 224 (0xE0) + // but i2c adressing uses the high 7 bits so it's 112 + Wire.write(byte(0x00)); // sets register pointer to the command register (0x00) + Wire.write(byte(0x50)); // command sensor to measure in "inches" (0x50) + // use 0x51 for centimeters + // use 0x52 for ping microseconds + Wire.endTransmission(); // stop transmitting + + // step 2: wait for readings to happen + delay(70); // datasheet suggests at least 65 milliseconds + + // step 3: instruct sensor to return a particular echo reading + Wire.beginTransmission(112); // transmit to device #112 + Wire.write(byte(0x02)); // sets register pointer to echo #1 register (0x02) + Wire.endTransmission(); // stop transmitting + + // step 4: request reading from sensor + Wire.requestFrom(112, 2); // request 2 bytes from slave device #112 + + // step 5: receive reading from sensor + if(2 <= Wire.available()) // if two bytes were received + { + reading = Wire.read(); // receive high byte (overwrites previous reading) + reading = reading << 8; // shift high byte to be high 8 bits + reading |= Wire.read(); // receive low byte as lower 8 bits + Serial.println(reading); // print the reading + } + + delay(250); // wait a bit since people have to read the output :) +} + + +/* + +// The following code changes the address of a Devantech Ultrasonic Range Finder (SRF10 or SRF08) +// usage: changeAddress(0x70, 0xE6); + +void changeAddress(byte oldAddress, byte newAddress) +{ + Wire.beginTransmission(oldAddress); + Wire.write(byte(0x00)); + Wire.write(byte(0xA0)); + Wire.endTransmission(); + + Wire.beginTransmission(oldAddress); + Wire.write(byte(0x00)); + Wire.write(byte(0xAA)); + Wire.endTransmission(); + + Wire.beginTransmission(oldAddress); + Wire.write(byte(0x00)); + Wire.write(byte(0xA5)); + Wire.endTransmission(); + + Wire.beginTransmission(oldAddress); + Wire.write(byte(0x00)); + Wire.write(newAddress); + Wire.endTransmission(); +} + +*/ diff --git a/hardware/sam/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.pde b/hardware/sam/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.pde new file mode 100644 index 000000000..38da1c543 --- /dev/null +++ b/hardware/sam/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.pde @@ -0,0 +1,39 @@ +// I2C Digital Potentiometer +// by Nicholas Zambetti +// and Shawn Bonkowski + +// Demonstrates use of the Wire library +// Controls AD5171 digital potentiometer via I2C/TWI + +// Created 31 March 2006 + +// This example code is in the public domain. + +// This example code is in the public domain. + + +#include + +void setup() +{ + Wire.begin(); // join i2c bus (address optional for master) +} + +byte val = 0; + +void loop() +{ + Wire.beginTransmission(44); // transmit to device #44 (0x2c) + // device address is specified in datasheet + Wire.write(byte(0x00)); // sends instruction byte + Wire.write(val); // sends potentiometer value byte + Wire.endTransmission(); // stop transmitting + + val++; // increment value + if(val == 64) // if reached 64th position (max) + { + val = 0; // start over from lowest value + } + delay(500); +} + diff --git a/hardware/sam/libraries/Wire/examples/master_reader/master_reader.pde b/hardware/sam/libraries/Wire/examples/master_reader/master_reader.pde new file mode 100644 index 000000000..4124d7d6b --- /dev/null +++ b/hardware/sam/libraries/Wire/examples/master_reader/master_reader.pde @@ -0,0 +1,32 @@ +// Wire Master Reader +// by Nicholas Zambetti + +// Demonstrates use of the Wire library +// Reads data from an I2C/TWI slave device +// Refer to the "Wire Slave Sender" example for use with this + +// Created 29 March 2006 + +// This example code is in the public domain. + + +#include + +void setup() +{ + Wire.begin(); // join i2c bus (address optional for master) + Serial.begin(9600); // start serial for output +} + +void loop() +{ + Wire.requestFrom(2, 6); // request 6 bytes from slave device #2 + + while(Wire.available()) // slave may send less than requested + { + char c = Wire.read(); // receive a byte as character + Serial.print(c); // print the character + } + + delay(500); +} diff --git a/hardware/sam/libraries/Wire/examples/master_writer/master_writer.pde b/hardware/sam/libraries/Wire/examples/master_writer/master_writer.pde new file mode 100644 index 000000000..ccaa0361b --- /dev/null +++ b/hardware/sam/libraries/Wire/examples/master_writer/master_writer.pde @@ -0,0 +1,31 @@ +// Wire Master Writer +// by Nicholas Zambetti + +// Demonstrates use of the Wire library +// Writes data to an I2C/TWI slave device +// Refer to the "Wire Slave Receiver" example for use with this + +// Created 29 March 2006 + +// This example code is in the public domain. + + +#include + +void setup() +{ + Wire.begin(); // join i2c bus (address optional for master) +} + +byte x = 0; + +void loop() +{ + Wire.beginTransmission(4); // transmit to device #4 + Wire.write("x is "); // sends five bytes + Wire.write(x); // sends one byte + Wire.endTransmission(); // stop transmitting + + x++; + delay(500); +} diff --git a/hardware/sam/libraries/Wire/examples/slave_receiver/slave_receiver.pde b/hardware/sam/libraries/Wire/examples/slave_receiver/slave_receiver.pde new file mode 100644 index 000000000..60dd4bdde --- /dev/null +++ b/hardware/sam/libraries/Wire/examples/slave_receiver/slave_receiver.pde @@ -0,0 +1,38 @@ +// Wire Slave Receiver +// by Nicholas Zambetti + +// Demonstrates use of the Wire library +// Receives data as an I2C/TWI slave device +// Refer to the "Wire Master Writer" example for use with this + +// Created 29 March 2006 + +// This example code is in the public domain. + + +#include + +void setup() +{ + Wire.begin(4); // join i2c bus with address #4 + Wire.onReceive(receiveEvent); // register event + Serial.begin(9600); // start serial for output +} + +void loop() +{ + delay(100); +} + +// function that executes whenever data is received from master +// this function is registered as an event, see setup() +void receiveEvent(int howMany) +{ + while(1 < Wire.available()) // loop through all but the last + { + char c = Wire.read(); // receive byte as a character + Serial.print(c); // print the character + } + int x = Wire.read(); // receive byte as an integer + Serial.println(x); // print the integer +} diff --git a/hardware/sam/libraries/Wire/examples/slave_sender/slave_sender.pde b/hardware/sam/libraries/Wire/examples/slave_sender/slave_sender.pde new file mode 100644 index 000000000..d3b238af9 --- /dev/null +++ b/hardware/sam/libraries/Wire/examples/slave_sender/slave_sender.pde @@ -0,0 +1,32 @@ +// Wire Slave Sender +// by Nicholas Zambetti + +// Demonstrates use of the Wire library +// Sends data as an I2C/TWI slave device +// Refer to the "Wire Master Reader" example for use with this + +// Created 29 March 2006 + +// This example code is in the public domain. + + +#include + +void setup() +{ + Wire.begin(2); // join i2c bus with address #2 + Wire.onRequest(requestEvent); // register event +} + +void loop() +{ + delay(100); +} + +// function that executes whenever data is requested by master +// this function is registered as an event, see setup() +void requestEvent() +{ + Wire.write("hello "); // respond with message of 6 bytes + // as expected by master +} diff --git a/hardware/sam/libraries/Wire/keywords.txt b/hardware/sam/libraries/Wire/keywords.txt new file mode 100644 index 000000000..12f129b99 --- /dev/null +++ b/hardware/sam/libraries/Wire/keywords.txt @@ -0,0 +1,31 @@ +####################################### +# Syntax Coloring Map For Wire +####################################### + +####################################### +# Datatypes (KEYWORD1) +####################################### + +####################################### +# Methods and Functions (KEYWORD2) +####################################### + +begin KEYWORD2 +beginTransmission KEYWORD2 +endTransmission KEYWORD2 +requestFrom KEYWORD2 +send KEYWORD2 +receive KEYWORD2 +onReceive KEYWORD2 +onRequest KEYWORD2 + +####################################### +# Instances (KEYWORD2) +####################################### + +Wire KEYWORD2 + +####################################### +# Constants (LITERAL1) +####################################### + diff --git a/hardware/sam/libraries/Wire/utility/twi.c b/hardware/sam/libraries/Wire/utility/twi.c new file mode 100644 index 000000000..cef8373a8 --- /dev/null +++ b/hardware/sam/libraries/Wire/utility/twi.c @@ -0,0 +1,476 @@ +/* + twi.c - TWI/I2C library for Wiring & Arduino + Copyright (c) 2006 Nicholas Zambetti. All right 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. + + 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 +*/ + +#include +#include +#include +#include +#include +#include + +#ifndef cbi +#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit)) +#endif + +#ifndef sbi +#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit)) +#endif + +#include "twi.h" + +static volatile uint8_t twi_state; +static uint8_t twi_slarw; + +static void (*twi_onSlaveTransmit)(void); +static void (*twi_onSlaveReceive)(uint8_t*, int); + +static uint8_t twi_masterBuffer[TWI_BUFFER_LENGTH]; +static volatile uint8_t twi_masterBufferIndex; +static uint8_t twi_masterBufferLength; + +static uint8_t twi_txBuffer[TWI_BUFFER_LENGTH]; +static volatile uint8_t twi_txBufferIndex; +static volatile uint8_t twi_txBufferLength; + +static uint8_t twi_rxBuffer[TWI_BUFFER_LENGTH]; +static volatile uint8_t twi_rxBufferIndex; + +static volatile uint8_t twi_error; + +/* + * Function twi_init + * Desc readys twi pins and sets twi bitrate + * Input none + * Output none + */ +void twi_init(void) +{ + // initialize state + twi_state = TWI_READY; + + #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 / TWI_FREQ) - 16) / 2; + + /* twi bit rate formula from atmega128 manual pg 204 + SCL Frequency = CPU Clock Frequency / (16 + (2 * TWBR)) + note: TWBR should be 10 or higher for master mode + It is 72 for a 16mhz Wiring board with 100kHz TWI */ + + // enable twi module, acks, and twi interrupt + TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA); +} + +/* + * Function twi_slaveInit + * Desc sets slave address and enables interrupt + * Input none + * Output none + */ +void twi_setAddress(uint8_t address) +{ + // set twi slave address (skip over TWGCE bit) + TWAR = address << 1; +} + +/* + * Function twi_readFrom + * Desc attempts to become twi bus master and read a + * series of bytes from a device on the bus + * Input address: 7bit i2c device address + * data: pointer to byte array + * length: number of bytes to read into array + * Output number of bytes read + */ +uint8_t twi_readFrom(uint8_t address, uint8_t* data, uint8_t length) +{ + uint8_t i; + + // ensure data will fit into buffer + if(TWI_BUFFER_LENGTH < length){ + return 0; + } + + // wait until twi is ready, become master receiver + while(TWI_READY != twi_state){ + continue; + } + twi_state = TWI_MRX; + // reset error state (0xFF.. no error occured) + twi_error = 0xFF; + + // initialize buffer iteration vars + twi_masterBufferIndex = 0; + twi_masterBufferLength = length-1; // This is not intuitive, read on... + // On receive, the previously configured ACK/NACK setting is transmitted in + // response to the received byte before the interrupt is signalled. + // Therefor we must actually set NACK when the _next_ to last byte is + // received, causing that NACK to be sent in response to receiving the last + // expected byte of data. + + // build sla+w, slave device address + w bit + twi_slarw = TW_READ; + twi_slarw |= address << 1; + + // send start condition + TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTA); + + // wait for read operation to complete + while(TWI_MRX == twi_state){ + continue; + } + + if (twi_masterBufferIndex < length) + length = twi_masterBufferIndex; + + // copy twi buffer to data + for(i = 0; i < length; ++i){ + data[i] = twi_masterBuffer[i]; + } + + return length; +} + +/* + * Function twi_writeTo + * Desc attempts to become twi bus master and write a + * series of bytes to a device on the bus + * Input address: 7bit i2c device address + * data: pointer to byte array + * length: number of bytes in array + * wait: boolean indicating to wait for write or not + * Output 0 .. success + * 1 .. length to long for buffer + * 2 .. address send, NACK received + * 3 .. data send, NACK received + * 4 .. other twi error (lost bus arbitration, bus error, ..) + */ +uint8_t twi_writeTo(uint8_t address, uint8_t* data, uint8_t length, uint8_t wait) +{ + uint8_t i; + + // ensure data will fit into buffer + if(TWI_BUFFER_LENGTH < length){ + return 1; + } + + // wait until twi is ready, become master transmitter + while(TWI_READY != twi_state){ + continue; + } + twi_state = TWI_MTX; + // reset error state (0xFF.. no error occured) + twi_error = 0xFF; + + // initialize buffer iteration vars + twi_masterBufferIndex = 0; + twi_masterBufferLength = length; + + // copy data to twi buffer + for(i = 0; i < length; ++i){ + twi_masterBuffer[i] = data[i]; + } + + // build sla+w, slave device address + w bit + twi_slarw = TW_WRITE; + twi_slarw |= address << 1; + + // send start condition + TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTA); + + // wait for write operation to complete + while(wait && (TWI_MTX == twi_state)){ + continue; + } + + if (twi_error == 0xFF) + return 0; // success + else if (twi_error == TW_MT_SLA_NACK) + return 2; // error: address send, nack received + else if (twi_error == TW_MT_DATA_NACK) + return 3; // error: data send, nack received + else + return 4; // other twi error +} + +/* + * Function twi_transmit + * Desc fills slave tx buffer with data + * must be called in slave tx event callback + * Input data: pointer to byte array + * length: number of bytes in array + * Output 1 length too long for buffer + * 2 not slave transmitter + * 0 ok + */ +uint8_t twi_transmit(const uint8_t* data, uint8_t length) +{ + uint8_t i; + + // ensure data will fit into buffer + if(TWI_BUFFER_LENGTH < length){ + return 1; + } + + // ensure we are currently a slave transmitter + if(TWI_STX != twi_state){ + return 2; + } + + // set length and copy data into tx buffer + twi_txBufferLength = length; + for(i = 0; i < length; ++i){ + twi_txBuffer[i] = data[i]; + } + + return 0; +} + +/* + * Function twi_attachSlaveRxEvent + * Desc sets function called before a slave read operation + * Input function: callback function to use + * Output none + */ +void twi_attachSlaveRxEvent( void (*function)(uint8_t*, int) ) +{ + twi_onSlaveReceive = function; +} + +/* + * Function twi_attachSlaveTxEvent + * Desc sets function called before a slave write operation + * Input function: callback function to use + * Output none + */ +void twi_attachSlaveTxEvent( void (*function)(void) ) +{ + twi_onSlaveTransmit = function; +} + +/* + * Function twi_reply + * Desc sends byte or readys receive line + * Input ack: byte indicating to ack or to nack + * Output none + */ +void twi_reply(uint8_t ack) +{ + // transmit master read ready signal, with or without ack + if(ack){ + TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT) | _BV(TWEA); + }else{ + TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT); + } +} + +/* + * Function twi_stop + * Desc relinquishes bus master status + * Input none + * Output none + */ +void twi_stop(void) +{ + // send stop condition + TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO); + + // wait for stop condition to be exectued on bus + // TWINT is not set after a stop condition! + while(TWCR & _BV(TWSTO)){ + continue; + } + + // update twi state + twi_state = TWI_READY; +} + +/* + * Function twi_releaseBus + * Desc releases bus control + * Input none + * Output none + */ +void twi_releaseBus(void) +{ + // release bus + TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT); + + // update twi state + twi_state = TWI_READY; +} + +SIGNAL(TWI_vect) +{ + switch(TW_STATUS){ + // All Master + case TW_START: // sent start condition + case TW_REP_START: // sent repeated start condition + // copy device address and r/w bit to output register and ack + TWDR = twi_slarw; + twi_reply(1); + break; + + // Master Transmitter + case TW_MT_SLA_ACK: // slave receiver acked address + case TW_MT_DATA_ACK: // slave receiver acked data + // if there is data to send, send it, otherwise stop + if(twi_masterBufferIndex < twi_masterBufferLength){ + // copy data to output register and ack + TWDR = twi_masterBuffer[twi_masterBufferIndex++]; + twi_reply(1); + }else{ + twi_stop(); + } + break; + case TW_MT_SLA_NACK: // address sent, nack received + twi_error = TW_MT_SLA_NACK; + twi_stop(); + break; + case TW_MT_DATA_NACK: // data sent, nack received + twi_error = TW_MT_DATA_NACK; + twi_stop(); + break; + case TW_MT_ARB_LOST: // lost bus arbitration + twi_error = TW_MT_ARB_LOST; + twi_releaseBus(); + break; + + // Master Receiver + case TW_MR_DATA_ACK: // data received, ack sent + // put byte into buffer + twi_masterBuffer[twi_masterBufferIndex++] = TWDR; + case TW_MR_SLA_ACK: // address sent, ack received + // ack if more bytes are expected, otherwise nack + if(twi_masterBufferIndex < twi_masterBufferLength){ + twi_reply(1); + }else{ + twi_reply(0); + } + break; + case TW_MR_DATA_NACK: // data received, nack sent + // put final byte into buffer + twi_masterBuffer[twi_masterBufferIndex++] = TWDR; + case TW_MR_SLA_NACK: // address sent, nack received + twi_stop(); + break; + // TW_MR_ARB_LOST handled by TW_MT_ARB_LOST case + + // Slave Receiver + case TW_SR_SLA_ACK: // addressed, returned ack + case TW_SR_GCALL_ACK: // addressed generally, returned ack + case TW_SR_ARB_LOST_SLA_ACK: // lost arbitration, returned ack + case TW_SR_ARB_LOST_GCALL_ACK: // lost arbitration, returned ack + // enter slave receiver mode + twi_state = TWI_SRX; + // indicate that rx buffer can be overwritten and ack + twi_rxBufferIndex = 0; + twi_reply(1); + break; + case TW_SR_DATA_ACK: // data received, returned ack + case TW_SR_GCALL_DATA_ACK: // data received generally, returned ack + // if there is still room in the rx buffer + if(twi_rxBufferIndex < TWI_BUFFER_LENGTH){ + // put byte in buffer and ack + twi_rxBuffer[twi_rxBufferIndex++] = TWDR; + twi_reply(1); + }else{ + // otherwise nack + twi_reply(0); + } + break; + case TW_SR_STOP: // stop or repeated start condition received + // put a null char after data if there's room + if(twi_rxBufferIndex < TWI_BUFFER_LENGTH){ + twi_rxBuffer[twi_rxBufferIndex] = '\0'; + } + // sends ack and stops interface for clock stretching + twi_stop(); + // callback to user defined callback + twi_onSlaveReceive(twi_rxBuffer, twi_rxBufferIndex); + // since we submit rx buffer to "wire" library, we can reset it + twi_rxBufferIndex = 0; + // ack future responses and leave slave receiver state + twi_releaseBus(); + break; + case TW_SR_DATA_NACK: // data received, returned nack + case TW_SR_GCALL_DATA_NACK: // data received generally, returned nack + // nack back at master + twi_reply(0); + break; + + // Slave Transmitter + case TW_ST_SLA_ACK: // addressed, returned ack + case TW_ST_ARB_LOST_SLA_ACK: // arbitration lost, returned ack + // enter slave transmitter mode + twi_state = TWI_STX; + // ready the tx buffer index for iteration + twi_txBufferIndex = 0; + // set tx buffer length to be zero, to verify if user changes it + twi_txBufferLength = 0; + // request for txBuffer to be filled and length to be set + // note: user must call twi_transmit(bytes, length) to do this + twi_onSlaveTransmit(); + // if they didn't change buffer & length, initialize it + if(0 == twi_txBufferLength){ + twi_txBufferLength = 1; + twi_txBuffer[0] = 0x00; + } + // transmit first byte from buffer, fall + case TW_ST_DATA_ACK: // byte sent, ack returned + // copy data to output register + TWDR = twi_txBuffer[twi_txBufferIndex++]; + // if there is more to send, ack, otherwise nack + if(twi_txBufferIndex < twi_txBufferLength){ + twi_reply(1); + }else{ + twi_reply(0); + } + break; + case TW_ST_DATA_NACK: // received nack, we are done + case TW_ST_LAST_DATA: // received ack, but we are done already! + // ack future responses + twi_reply(1); + // leave slave receiver state + twi_state = TWI_READY; + break; + + // All + case TW_NO_INFO: // no state information + break; + case TW_BUS_ERROR: // bus error, illegal stop/start + twi_error = TW_BUS_ERROR; + twi_stop(); + break; + } +} + diff --git a/hardware/sam/libraries/Wire/utility/twi.h b/hardware/sam/libraries/Wire/utility/twi.h new file mode 100644 index 000000000..831b9282a --- /dev/null +++ b/hardware/sam/libraries/Wire/utility/twi.h @@ -0,0 +1,53 @@ +/* + twi.h - TWI/I2C library for Wiring & Arduino + Copyright (c) 2006 Nicholas Zambetti. All right 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. + + 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 +*/ + +#ifndef twi_h +#define twi_h + + #include + + //#define ATMEGA8 + + #ifndef TWI_FREQ + #define TWI_FREQ 100000L + #endif + + #ifndef TWI_BUFFER_LENGTH + #define TWI_BUFFER_LENGTH 32 + #endif + + #define TWI_READY 0 + #define TWI_MRX 1 + #define TWI_MTX 2 + #define TWI_SRX 3 + #define TWI_STX 4 + + void twi_init(void); + void twi_setAddress(uint8_t); + uint8_t twi_readFrom(uint8_t, uint8_t*, uint8_t); + uint8_t twi_writeTo(uint8_t, uint8_t*, uint8_t, uint8_t); + uint8_t twi_transmit(const uint8_t*, uint8_t); + void twi_attachSlaveRxEvent( void (*)(uint8_t*, int) ); + void twi_attachSlaveTxEvent( void (*)(void) ); + void twi_reply(uint8_t); + void twi_stop(void); + void twi_releaseBus(void); + +#endif +