![](/media/cache/img/default_profile.jpg.50x50_q85.jpg)
I2C not yet integrated
Tested working with single and differential voltages.
Connect SCL (pin 11) to D15 Connect SDA (pin 10) to D14 Connect pin 16 to +5v Connect pin 9 to gnd
LT_I2C.cpp@2:c9e727dcd00e, 2016-12-06 (annotated)
- Committer:
- lrdawg99
- Date:
- Tue Dec 06 18:34:46 2016 +0000
- Revision:
- 2:c9e727dcd00e
- Parent:
- 1:4e4194db7cd6
made object oriented
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
lrdawg99 | 0:1473318f27b6 | 1 | |
lrdawg99 | 0:1473318f27b6 | 2 | /*! |
lrdawg99 | 0:1473318f27b6 | 3 | LT_I2C: Routines to communicate with ATmega328P's hardware I2C port. |
lrdawg99 | 0:1473318f27b6 | 4 | |
lrdawg99 | 0:1473318f27b6 | 5 | @verbatim |
lrdawg99 | 0:1473318f27b6 | 6 | |
lrdawg99 | 0:1473318f27b6 | 7 | LT_I2C contains the low level routines to communicate with devices using the |
lrdawg99 | 0:1473318f27b6 | 8 | ATMega328's onboard hardware I2C port. Each routine checks the Two Wire Status |
lrdawg99 | 0:1473318f27b6 | 9 | Register (TWSR) at the end of the transaction and returns 0 if successful and 1 |
lrdawg99 | 0:1473318f27b6 | 10 | if not successful. |
lrdawg99 | 0:1473318f27b6 | 11 | |
lrdawg99 | 0:1473318f27b6 | 12 | I2C Frequency = (CPU Clock frequency)/(16+2(TWBR)*Prescaler) |
lrdawg99 | 0:1473318f27b6 | 13 | |
lrdawg99 | 0:1473318f27b6 | 14 | TWBR-Two Wire Bit Rate Register |
lrdawg99 | 0:1473318f27b6 | 15 | TWCR=Two Wire Control Register (TWINT TWEA TWSTA TWSTO TWWC TWEN - TWIE) |
lrdawg99 | 0:1473318f27b6 | 16 | TWSR=Two Wire Status Register |
lrdawg99 | 0:1473318f27b6 | 17 | |
lrdawg99 | 0:1473318f27b6 | 18 | Prescaler Values: |
lrdawg99 | 0:1473318f27b6 | 19 | TWSR1 TWSR0 Prescaler |
lrdawg99 | 0:1473318f27b6 | 20 | 0 0 1 |
lrdawg99 | 0:1473318f27b6 | 21 | 0 1 4 |
lrdawg99 | 0:1473318f27b6 | 22 | 1 0 16 |
lrdawg99 | 0:1473318f27b6 | 23 | 1 1 64 |
lrdawg99 | 0:1473318f27b6 | 24 | |
lrdawg99 | 0:1473318f27b6 | 25 | Examples: |
lrdawg99 | 0:1473318f27b6 | 26 | CPU Frequency = 16Mhz on Arduino Uno |
lrdawg99 | 0:1473318f27b6 | 27 | I2C Frequency Prescaler TWSR1 TWSR0 TWBR |
lrdawg99 | 0:1473318f27b6 | 28 | 1khz 64 1 1 125 |
lrdawg99 | 0:1473318f27b6 | 29 | 10khz 64 1 1 12 |
lrdawg99 | 0:1473318f27b6 | 30 | 50khz 16 1 0 10 |
lrdawg99 | 0:1473318f27b6 | 31 | 100khz 4 0 1 18 |
lrdawg99 | 0:1473318f27b6 | 32 | 400khz 1 0 0 12 |
lrdawg99 | 0:1473318f27b6 | 33 | |
lrdawg99 | 0:1473318f27b6 | 34 | @endverbatim |
lrdawg99 | 0:1473318f27b6 | 35 | |
lrdawg99 | 0:1473318f27b6 | 36 | REVISION HISTORY |
lrdawg99 | 0:1473318f27b6 | 37 | $Revision: 5469 $ |
lrdawg99 | 0:1473318f27b6 | 38 | $Date: 2016-07-22 17:01:32 -0700 (Fri, 22 Jul 2016) $ |
lrdawg99 | 0:1473318f27b6 | 39 | |
lrdawg99 | 0:1473318f27b6 | 40 | Copyright (c) 2013, Linear Technology Corp.(LTC) |
lrdawg99 | 0:1473318f27b6 | 41 | All rights reserved. |
lrdawg99 | 0:1473318f27b6 | 42 | |
lrdawg99 | 0:1473318f27b6 | 43 | Redistribution and use in source and binary forms, with or without |
lrdawg99 | 0:1473318f27b6 | 44 | modification, are permitted provided that the following conditions are met: |
lrdawg99 | 0:1473318f27b6 | 45 | |
lrdawg99 | 0:1473318f27b6 | 46 | 1. Redistributions of source code must retain the above copyright notice, this |
lrdawg99 | 0:1473318f27b6 | 47 | list of conditions and the following disclaimer. |
lrdawg99 | 0:1473318f27b6 | 48 | 2. Redistributions in binary form must reproduce the above copyright notice, |
lrdawg99 | 0:1473318f27b6 | 49 | this list of conditions and the following disclaimer in the documentation |
lrdawg99 | 0:1473318f27b6 | 50 | and/or other materials provided with the distribution. |
lrdawg99 | 0:1473318f27b6 | 51 | |
lrdawg99 | 0:1473318f27b6 | 52 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND |
lrdawg99 | 0:1473318f27b6 | 53 | ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
lrdawg99 | 0:1473318f27b6 | 54 | WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
lrdawg99 | 0:1473318f27b6 | 55 | DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR |
lrdawg99 | 0:1473318f27b6 | 56 | ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
lrdawg99 | 0:1473318f27b6 | 57 | (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
lrdawg99 | 0:1473318f27b6 | 58 | LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
lrdawg99 | 0:1473318f27b6 | 59 | ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
lrdawg99 | 0:1473318f27b6 | 60 | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
lrdawg99 | 0:1473318f27b6 | 61 | SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
lrdawg99 | 0:1473318f27b6 | 62 | |
lrdawg99 | 0:1473318f27b6 | 63 | The views and conclusions contained in the software and documentation are those |
lrdawg99 | 0:1473318f27b6 | 64 | of the authors and should not be interpreted as representing official policies, |
lrdawg99 | 0:1473318f27b6 | 65 | either expressed or implied, of Linear Technology Corp. |
lrdawg99 | 0:1473318f27b6 | 66 | |
lrdawg99 | 0:1473318f27b6 | 67 | The Linear Technology Linduino is not affiliated with the official Arduino team. |
lrdawg99 | 0:1473318f27b6 | 68 | However, the Linduino is only possible because of the Arduino team's commitment |
lrdawg99 | 0:1473318f27b6 | 69 | to the open-source community. Please, visit http://www.arduino.cc and |
lrdawg99 | 0:1473318f27b6 | 70 | http://store.arduino.cc , and consider a purchase that will help fund their |
lrdawg99 | 0:1473318f27b6 | 71 | ongoing work. |
lrdawg99 | 0:1473318f27b6 | 72 | */ |
lrdawg99 | 0:1473318f27b6 | 73 | |
lrdawg99 | 0:1473318f27b6 | 74 | //! @defgroup LT_I2C LT_I2C: Routines to Communicate With ATmega328P's hardware I2C port. |
lrdawg99 | 0:1473318f27b6 | 75 | |
lrdawg99 | 0:1473318f27b6 | 76 | /*! @file |
lrdawg99 | 0:1473318f27b6 | 77 | @ingroup LT_I2C |
lrdawg99 | 0:1473318f27b6 | 78 | Library for LT_I2C: Routines to Communicate With ATmega328P's hardware I2C port. |
lrdawg99 | 0:1473318f27b6 | 79 | */ |
lrdawg99 | 0:1473318f27b6 | 80 | |
lrdawg99 | 0:1473318f27b6 | 81 | //#include <Arduino.h> |
lrdawg99 | 0:1473318f27b6 | 82 | #include <stdint.h> |
lrdawg99 | 0:1473318f27b6 | 83 | //#include <util/delay.h> |
lrdawg99 | 0:1473318f27b6 | 84 | #include "Linduino.h" |
lrdawg99 | 0:1473318f27b6 | 85 | #include "LT_I2C.h" |
lrdawg99 | 1:4e4194db7cd6 | 86 | #include "mbed.h" |
lrdawg99 | 0:1473318f27b6 | 87 | |
lrdawg99 | 0:1473318f27b6 | 88 | //! CPU master clock frequency |
lrdawg99 | 0:1473318f27b6 | 89 | #ifndef F_CPU |
lrdawg99 | 0:1473318f27b6 | 90 | #define F_CPU 16000000UL |
lrdawg99 | 0:1473318f27b6 | 91 | #endif |
lrdawg99 | 1:4e4194db7cd6 | 92 | Serial pc1(USBTX, USBRX, 9600); |
lrdawg99 | 0:1473318f27b6 | 93 | |
lrdawg99 | 0:1473318f27b6 | 94 | |
lrdawg99 | 2:c9e727dcd00e | 95 | LT_I2C::LT_I2C() { |
lrdawg99 | 2:c9e727dcd00e | 96 | i2c = new I2C(I2C_SDA, I2C_SCL); |
lrdawg99 | 2:c9e727dcd00e | 97 | i2c->frequency(400000); //maximum from datasheet for ltc2991 |
lrdawg99 | 2:c9e727dcd00e | 98 | } |
lrdawg99 | 2:c9e727dcd00e | 99 | |
lrdawg99 | 2:c9e727dcd00e | 100 | LT_I2C::LT_I2C(PinName sda_, PinName scl_) { |
lrdawg99 | 2:c9e727dcd00e | 101 | sda = sda_; |
lrdawg99 | 2:c9e727dcd00e | 102 | scl = scl_; |
lrdawg99 | 2:c9e727dcd00e | 103 | i2c = new I2C(sda_ , scl_); |
lrdawg99 | 2:c9e727dcd00e | 104 | i2c->frequency(400000); //maximum from datasheet for ltc2991 |
lrdawg99 | 2:c9e727dcd00e | 105 | } |
lrdawg99 | 0:1473318f27b6 | 106 | |
lrdawg99 | 0:1473318f27b6 | 107 | // Read a byte of data at register specified by "command", store in "value" |
lrdawg99 | 2:c9e727dcd00e | 108 | int8_t LT_I2C::i2c_read_byte_data(uint8_t address, uint8_t command, uint8_t *value) |
lrdawg99 | 0:1473318f27b6 | 109 | { |
lrdawg99 | 1:4e4194db7cd6 | 110 | int8_t ret = 0; |
lrdawg99 | 1:4e4194db7cd6 | 111 | |
lrdawg99 | 1:4e4194db7cd6 | 112 | char cmd1[1]; |
lrdawg99 | 1:4e4194db7cd6 | 113 | cmd1[0] = command; |
lrdawg99 | 1:4e4194db7cd6 | 114 | char v[1]; |
lrdawg99 | 1:4e4194db7cd6 | 115 | v[0] = 0; |
lrdawg99 | 1:4e4194db7cd6 | 116 | |
lrdawg99 | 2:c9e727dcd00e | 117 | ret |= i2c->write((address<<1) | I2C_WRITE_BIT, cmd1, 1, true); |
lrdawg99 | 2:c9e727dcd00e | 118 | ret |= i2c->read((address<<1) | I2C_READ_BIT, v, 1, false); |
lrdawg99 | 1:4e4194db7cd6 | 119 | |
lrdawg99 | 1:4e4194db7cd6 | 120 | *value = v[0]; |
lrdawg99 | 1:4e4194db7cd6 | 121 | |
lrdawg99 | 1:4e4194db7cd6 | 122 | if (ret == 0) { |
lrdawg99 | 1:4e4194db7cd6 | 123 | return 0; //success |
lrdawg99 | 1:4e4194db7cd6 | 124 | } |
lrdawg99 | 1:4e4194db7cd6 | 125 | return(1); |
lrdawg99 | 0:1473318f27b6 | 126 | } |
lrdawg99 | 0:1473318f27b6 | 127 | |
lrdawg99 | 0:1473318f27b6 | 128 | // Write a byte of data to register specified by "command" |
lrdawg99 | 2:c9e727dcd00e | 129 | int8_t LT_I2C::i2c_write_byte_data(uint8_t address, uint8_t command, uint8_t value) |
lrdawg99 | 0:1473318f27b6 | 130 | { |
lrdawg99 | 1:4e4194db7cd6 | 131 | int8_t ret = 0; |
lrdawg99 | 1:4e4194db7cd6 | 132 | char cmd[2]; |
lrdawg99 | 1:4e4194db7cd6 | 133 | cmd[0] = command; |
lrdawg99 | 1:4e4194db7cd6 | 134 | cmd[1] = value; |
lrdawg99 | 2:c9e727dcd00e | 135 | ret |= i2c->write((address<<1) | I2C_WRITE_BIT, cmd, 2, false); |
lrdawg99 | 1:4e4194db7cd6 | 136 | |
lrdawg99 | 1:4e4194db7cd6 | 137 | if (ret == 0) { |
lrdawg99 | 1:4e4194db7cd6 | 138 | return 0; //success |
lrdawg99 | 1:4e4194db7cd6 | 139 | } |
lrdawg99 | 1:4e4194db7cd6 | 140 | return(1); |
lrdawg99 | 0:1473318f27b6 | 141 | } |
lrdawg99 | 0:1473318f27b6 | 142 | |
lrdawg99 | 2:c9e727dcd00e | 143 | int8_t LT_I2C::i2c_read_word_data(uint8_t address, uint8_t command, uint16_t *value) |
lrdawg99 | 0:1473318f27b6 | 144 | { |
lrdawg99 | 1:4e4194db7cd6 | 145 | int8_t ret = 0; |
lrdawg99 | 1:4e4194db7cd6 | 146 | |
lrdawg99 | 1:4e4194db7cd6 | 147 | |
lrdawg99 | 1:4e4194db7cd6 | 148 | union { |
lrdawg99 | 1:4e4194db7cd6 | 149 | char b[2]; |
lrdawg99 | 1:4e4194db7cd6 | 150 | uint16_t w; |
lrdawg99 | 1:4e4194db7cd6 | 151 | } data; |
lrdawg99 | 1:4e4194db7cd6 | 152 | |
lrdawg99 | 1:4e4194db7cd6 | 153 | char writedata[2]; |
lrdawg99 | 1:4e4194db7cd6 | 154 | writedata[0] = command; //msb |
lrdawg99 | 1:4e4194db7cd6 | 155 | writedata[1] = command+1; //lsb |
lrdawg99 | 1:4e4194db7cd6 | 156 | |
lrdawg99 | 2:c9e727dcd00e | 157 | ret |= i2c->write((address << 1) | I2C_WRITE_BIT, &writedata[0], 1, true); |
lrdawg99 | 2:c9e727dcd00e | 158 | ret |= i2c->read((address << 1) | I2C_READ_BIT, &data.b[1], 1, false); |
lrdawg99 | 2:c9e727dcd00e | 159 | ret |= i2c->write((address << 1) | I2C_WRITE_BIT, &writedata[1], 1, true); |
lrdawg99 | 2:c9e727dcd00e | 160 | ret |= i2c->read((address << 1) | I2C_READ_BIT, &data.b[0], 1, false); |
lrdawg99 | 1:4e4194db7cd6 | 161 | |
lrdawg99 | 1:4e4194db7cd6 | 162 | |
lrdawg99 | 1:4e4194db7cd6 | 163 | *value = data.w; |
lrdawg99 | 1:4e4194db7cd6 | 164 | |
lrdawg99 | 1:4e4194db7cd6 | 165 | if (ret == 0) { |
lrdawg99 | 1:4e4194db7cd6 | 166 | return 0; |
lrdawg99 | 1:4e4194db7cd6 | 167 | } |
lrdawg99 | 1:4e4194db7cd6 | 168 | return(1); |
lrdawg99 | 0:1473318f27b6 | 169 | } |
lrdawg99 | 0:1473318f27b6 | 170 | |
lrdawg99 | 0:1473318f27b6 | 171 | // Write a 16-bit word of data to register specified by "command" |
lrdawg99 | 2:c9e727dcd00e | 172 | int8_t LT_I2C::i2c_write_word_data(uint8_t address, uint8_t command, uint16_t value) |
lrdawg99 | 0:1473318f27b6 | 173 | { |
lrdawg99 | 1:4e4194db7cd6 | 174 | int8_t ret = 0; |
lrdawg99 | 1:4e4194db7cd6 | 175 | |
lrdawg99 | 1:4e4194db7cd6 | 176 | union |
lrdawg99 | 1:4e4194db7cd6 | 177 | { |
lrdawg99 | 1:4e4194db7cd6 | 178 | uint8_t b[2]; |
lrdawg99 | 1:4e4194db7cd6 | 179 | uint16_t w; |
lrdawg99 | 1:4e4194db7cd6 | 180 | } data; |
lrdawg99 | 1:4e4194db7cd6 | 181 | data.w = value; |
lrdawg99 | 1:4e4194db7cd6 | 182 | |
lrdawg99 | 1:4e4194db7cd6 | 183 | char cmd[3]; |
lrdawg99 | 1:4e4194db7cd6 | 184 | cmd[0] = command; |
lrdawg99 | 1:4e4194db7cd6 | 185 | cmd[1] = data.b[1]; |
lrdawg99 | 1:4e4194db7cd6 | 186 | cmd[2] = data.b[0]; |
lrdawg99 | 0:1473318f27b6 | 187 | |
lrdawg99 | 2:c9e727dcd00e | 188 | ret |= i2c->write((address<<1) | I2C_WRITE_BIT, cmd, 3, false); |
lrdawg99 | 0:1473318f27b6 | 189 | |
lrdawg99 | 1:4e4194db7cd6 | 190 | if (ret == 0) { |
lrdawg99 | 1:4e4194db7cd6 | 191 | return 0; |
lrdawg99 | 1:4e4194db7cd6 | 192 | } |
lrdawg99 | 1:4e4194db7cd6 | 193 | return(1); |
lrdawg99 | 1:4e4194db7cd6 | 194 | } |