![](/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@0:1473318f27b6, 2016-11-16 (annotated)
- Committer:
- lrdawg99
- Date:
- Wed Nov 16 15:54:08 2016 +0000
- Revision:
- 0:1473318f27b6
- Child:
- 1:4e4194db7cd6
Ready to integrate I2C into LT_I2C
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 | 0:1473318f27b6 | 86 | |
lrdawg99 | 0:1473318f27b6 | 87 | //! CPU master clock frequency |
lrdawg99 | 0:1473318f27b6 | 88 | #ifndef F_CPU |
lrdawg99 | 0:1473318f27b6 | 89 | #define F_CPU 16000000UL |
lrdawg99 | 0:1473318f27b6 | 90 | #endif |
lrdawg99 | 0:1473318f27b6 | 91 | |
lrdawg99 | 0:1473318f27b6 | 92 | // Read a byte, store in "value". |
lrdawg99 | 0:1473318f27b6 | 93 | int8_t i2c_read_byte(uint8_t address, uint8_t *value) |
lrdawg99 | 0:1473318f27b6 | 94 | { |
lrdawg99 | 0:1473318f27b6 | 95 | //uint8_t ret=0; |
lrdawg99 | 0:1473318f27b6 | 96 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 97 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 98 | // ret |= i2c_write((address<<1)|I2C_READ_BIT); // Write the I2C 7-bit address with R bit |
lrdawg99 | 0:1473318f27b6 | 99 | // if (ret != 0) // Returns 1 if failed |
lrdawg99 | 0:1473318f27b6 | 100 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 101 | // |
lrdawg99 | 0:1473318f27b6 | 102 | // *value = i2c_read(WITH_NACK); // Read byte from I2C Bus with NAK |
lrdawg99 | 0:1473318f27b6 | 103 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 104 | // return(0); // Return success |
lrdawg99 | 0:1473318f27b6 | 105 | return 0; |
lrdawg99 | 0:1473318f27b6 | 106 | |
lrdawg99 | 0:1473318f27b6 | 107 | } |
lrdawg99 | 0:1473318f27b6 | 108 | |
lrdawg99 | 0:1473318f27b6 | 109 | // Write "value" byte to device at "address" |
lrdawg99 | 0:1473318f27b6 | 110 | int8_t i2c_write_byte(uint8_t address, uint8_t value) |
lrdawg99 | 0:1473318f27b6 | 111 | { |
lrdawg99 | 0:1473318f27b6 | 112 | //int8_t ret= 0 ; |
lrdawg99 | 0:1473318f27b6 | 113 | // |
lrdawg99 | 0:1473318f27b6 | 114 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 115 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 116 | // ret |= i2c_write((address<<1)|I2C_WRITE_BIT); //Write the I2C 7 bit address with W bit |
lrdawg99 | 0:1473318f27b6 | 117 | // ret |= i2c_write(value); //Write value |
lrdawg99 | 0:1473318f27b6 | 118 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 119 | // if (ret!=0) // Returns 1 if failed |
lrdawg99 | 0:1473318f27b6 | 120 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 121 | // return(0); // Returns 0 if success |
lrdawg99 | 0:1473318f27b6 | 122 | return 0; |
lrdawg99 | 0:1473318f27b6 | 123 | } |
lrdawg99 | 0:1473318f27b6 | 124 | |
lrdawg99 | 0:1473318f27b6 | 125 | // Read a byte of data at register specified by "command", store in "value" |
lrdawg99 | 0:1473318f27b6 | 126 | int8_t i2c_read_byte_data(uint8_t address, uint8_t command, uint8_t *value) |
lrdawg99 | 0:1473318f27b6 | 127 | { |
lrdawg99 | 0:1473318f27b6 | 128 | //int8_t ret = 0; |
lrdawg99 | 0:1473318f27b6 | 129 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 130 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 131 | // ret |= i2c_write((address<<1)|I2C_WRITE_BIT); // Write 7 bit address with W bit |
lrdawg99 | 0:1473318f27b6 | 132 | // ret|= i2c_write(command); // Set register to be read to command |
lrdawg99 | 0:1473318f27b6 | 133 | // if (i2c_start()!=0) //I2C repeated START |
lrdawg99 | 0:1473318f27b6 | 134 | // { |
lrdawg99 | 0:1473318f27b6 | 135 | // i2c_stop(); //Attempt to issue I2C STOP |
lrdawg99 | 0:1473318f27b6 | 136 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 137 | // } |
lrdawg99 | 0:1473318f27b6 | 138 | // ret |= i2c_write((address<<1)|I2C_READ_BIT); // Write 7 bit address with R bit |
lrdawg99 | 0:1473318f27b6 | 139 | // *value = i2c_read(WITH_NACK); // Read byte from buffer with NAK |
lrdawg99 | 0:1473318f27b6 | 140 | // i2c_stop(); // I2C STOP |
lrdawg99 | 0:1473318f27b6 | 141 | // if (ret!=0) //If there was a NAK return 1 |
lrdawg99 | 0:1473318f27b6 | 142 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 143 | // return(0); // Return success |
lrdawg99 | 0:1473318f27b6 | 144 | return 0; |
lrdawg99 | 0:1473318f27b6 | 145 | } |
lrdawg99 | 0:1473318f27b6 | 146 | |
lrdawg99 | 0:1473318f27b6 | 147 | // Write a byte of data to register specified by "command" |
lrdawg99 | 0:1473318f27b6 | 148 | int8_t i2c_write_byte_data(uint8_t address, uint8_t command, uint8_t value) |
lrdawg99 | 0:1473318f27b6 | 149 | { |
lrdawg99 | 0:1473318f27b6 | 150 | //int8_t ret = 0; |
lrdawg99 | 0:1473318f27b6 | 151 | // |
lrdawg99 | 0:1473318f27b6 | 152 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 153 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 154 | // ret |= i2c_write((address<<1)|I2C_WRITE_BIT); // Write 7 bit address with W bit |
lrdawg99 | 0:1473318f27b6 | 155 | // ret|= i2c_write(command); // Set register to be read to command |
lrdawg99 | 0:1473318f27b6 | 156 | // ret|= i2c_write(value); |
lrdawg99 | 0:1473318f27b6 | 157 | // i2c_stop(); // I2C STOP |
lrdawg99 | 0:1473318f27b6 | 158 | // |
lrdawg99 | 0:1473318f27b6 | 159 | // if (ret!=0) //If there was a NAK return 1 |
lrdawg99 | 0:1473318f27b6 | 160 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 161 | // return(0); // Return success |
lrdawg99 | 0:1473318f27b6 | 162 | return 0; |
lrdawg99 | 0:1473318f27b6 | 163 | } |
lrdawg99 | 0:1473318f27b6 | 164 | |
lrdawg99 | 0:1473318f27b6 | 165 | // Read a 16-bit word of data from register specified by "command" |
lrdawg99 | 0:1473318f27b6 | 166 | int8_t i2c_read_word_data(uint8_t address, uint8_t command, uint16_t *value) |
lrdawg99 | 0:1473318f27b6 | 167 | { |
lrdawg99 | 0:1473318f27b6 | 168 | //int8_t ret = 0; |
lrdawg99 | 0:1473318f27b6 | 169 | // |
lrdawg99 | 0:1473318f27b6 | 170 | // union |
lrdawg99 | 0:1473318f27b6 | 171 | // { |
lrdawg99 | 0:1473318f27b6 | 172 | // uint8_t b[2]; |
lrdawg99 | 0:1473318f27b6 | 173 | // uint16_t w; |
lrdawg99 | 0:1473318f27b6 | 174 | // } data; |
lrdawg99 | 0:1473318f27b6 | 175 | // |
lrdawg99 | 0:1473318f27b6 | 176 | // |
lrdawg99 | 0:1473318f27b6 | 177 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 178 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 179 | // ret |= i2c_write((address<<1)|I2C_WRITE_BIT); // Write 7 bit address with W bit |
lrdawg99 | 0:1473318f27b6 | 180 | // ret |= i2c_write(command); // Set register to be read to command |
lrdawg99 | 0:1473318f27b6 | 181 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 182 | // { |
lrdawg99 | 0:1473318f27b6 | 183 | // i2c_stop(); //Attempt to issue I2C STOP |
lrdawg99 | 0:1473318f27b6 | 184 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 185 | // } |
lrdawg99 | 0:1473318f27b6 | 186 | // ret |= i2c_write((address<<1)|I2C_READ_BIT); // Write 7 bit address with R bit |
lrdawg99 | 0:1473318f27b6 | 187 | // |
lrdawg99 | 0:1473318f27b6 | 188 | // data.b[1] = i2c_read(WITH_ACK); // Read MSB from buffer |
lrdawg99 | 0:1473318f27b6 | 189 | // data.b[0] = i2c_read(WITH_NACK); // Read LSB from buffer |
lrdawg99 | 0:1473318f27b6 | 190 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 191 | // |
lrdawg99 | 0:1473318f27b6 | 192 | // *value = data.w; |
lrdawg99 | 0:1473318f27b6 | 193 | // |
lrdawg99 | 0:1473318f27b6 | 194 | // if (ret!=0) //If NAK |
lrdawg99 | 0:1473318f27b6 | 195 | // return (1); //return 1 |
lrdawg99 | 0:1473318f27b6 | 196 | // return(0); // Return success |
lrdawg99 | 0:1473318f27b6 | 197 | return 0; |
lrdawg99 | 0:1473318f27b6 | 198 | } |
lrdawg99 | 0:1473318f27b6 | 199 | |
lrdawg99 | 0:1473318f27b6 | 200 | // Write a 16-bit word of data to register specified by "command" |
lrdawg99 | 0:1473318f27b6 | 201 | int8_t i2c_write_word_data(uint8_t address, uint8_t command, uint16_t value) |
lrdawg99 | 0:1473318f27b6 | 202 | { |
lrdawg99 | 0:1473318f27b6 | 203 | //int8_t ret=0; |
lrdawg99 | 0:1473318f27b6 | 204 | // |
lrdawg99 | 0:1473318f27b6 | 205 | // union |
lrdawg99 | 0:1473318f27b6 | 206 | // { |
lrdawg99 | 0:1473318f27b6 | 207 | // uint8_t b[2]; |
lrdawg99 | 0:1473318f27b6 | 208 | // uint16_t w; |
lrdawg99 | 0:1473318f27b6 | 209 | // } data; |
lrdawg99 | 0:1473318f27b6 | 210 | // data.w = value; |
lrdawg99 | 0:1473318f27b6 | 211 | // |
lrdawg99 | 0:1473318f27b6 | 212 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 213 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 214 | // ret |= i2c_write((address<<1)|I2C_WRITE_BIT); // Write 7 bit address with W bit |
lrdawg99 | 0:1473318f27b6 | 215 | // ret|= i2c_write(command); // Set register to be read to command |
lrdawg99 | 0:1473318f27b6 | 216 | // ret|= i2c_write(data.b[1]); //Write MSB |
lrdawg99 | 0:1473318f27b6 | 217 | // ret|= i2c_write(data.b[0]); //Write LSB; |
lrdawg99 | 0:1473318f27b6 | 218 | // |
lrdawg99 | 0:1473318f27b6 | 219 | // i2c_stop(); // I2C STOP |
lrdawg99 | 0:1473318f27b6 | 220 | // |
lrdawg99 | 0:1473318f27b6 | 221 | // if (ret!=0) //If there was a NAK return 1 |
lrdawg99 | 0:1473318f27b6 | 222 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 223 | // return(0); |
lrdawg99 | 0:1473318f27b6 | 224 | |
lrdawg99 | 0:1473318f27b6 | 225 | return 0; |
lrdawg99 | 0:1473318f27b6 | 226 | } |
lrdawg99 | 0:1473318f27b6 | 227 | |
lrdawg99 | 0:1473318f27b6 | 228 | // Read a block of data, starting at register specified by "command" and ending at (command + length - 1) |
lrdawg99 | 0:1473318f27b6 | 229 | int8_t i2c_read_block_data(uint8_t address, uint8_t command, uint8_t length, uint8_t *values) |
lrdawg99 | 0:1473318f27b6 | 230 | { |
lrdawg99 | 0:1473318f27b6 | 231 | //uint8_t i = (length-1); |
lrdawg99 | 0:1473318f27b6 | 232 | // int8_t ret = 0; |
lrdawg99 | 0:1473318f27b6 | 233 | // |
lrdawg99 | 0:1473318f27b6 | 234 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 235 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 236 | // ret |= i2c_write((address<<1)|I2C_WRITE_BIT); //Write 7-bit address with W bit |
lrdawg99 | 0:1473318f27b6 | 237 | // if (ret!=0) //If NACK return 1 |
lrdawg99 | 0:1473318f27b6 | 238 | // { |
lrdawg99 | 0:1473318f27b6 | 239 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 240 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 241 | // } |
lrdawg99 | 0:1473318f27b6 | 242 | // ret|= i2c_write(command); //Write 8 bit command word |
lrdawg99 | 0:1473318f27b6 | 243 | // if (ret!=0) //If NACK return 1 |
lrdawg99 | 0:1473318f27b6 | 244 | // { |
lrdawg99 | 0:1473318f27b6 | 245 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 246 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 247 | // } |
lrdawg99 | 0:1473318f27b6 | 248 | // if (i2c_start()!=0) //I2C repeated START |
lrdawg99 | 0:1473318f27b6 | 249 | // { |
lrdawg99 | 0:1473318f27b6 | 250 | // i2c_stop(); //Attempt to issue I2C STOP |
lrdawg99 | 0:1473318f27b6 | 251 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 252 | // } |
lrdawg99 | 0:1473318f27b6 | 253 | // ret |= i2c_write((address<<1)|I2C_READ_BIT); //Write 7-bit address with R bit |
lrdawg99 | 0:1473318f27b6 | 254 | // |
lrdawg99 | 0:1473318f27b6 | 255 | // if (ret!=0) //If NACK return 1 |
lrdawg99 | 0:1473318f27b6 | 256 | // { |
lrdawg99 | 0:1473318f27b6 | 257 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 258 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 259 | // } |
lrdawg99 | 0:1473318f27b6 | 260 | // while (i>0) //Begin read loop |
lrdawg99 | 0:1473318f27b6 | 261 | // { |
lrdawg99 | 0:1473318f27b6 | 262 | // values[i] = i2c_read(WITH_ACK); //Read from bus with ACK |
lrdawg99 | 0:1473318f27b6 | 263 | // i--; |
lrdawg99 | 0:1473318f27b6 | 264 | // } |
lrdawg99 | 0:1473318f27b6 | 265 | // |
lrdawg99 | 0:1473318f27b6 | 266 | // values[0] = i2c_read(WITH_NACK); //Read from bus with NACK for the last one; |
lrdawg99 | 0:1473318f27b6 | 267 | // |
lrdawg99 | 0:1473318f27b6 | 268 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 269 | // |
lrdawg99 | 0:1473318f27b6 | 270 | // |
lrdawg99 | 0:1473318f27b6 | 271 | // return(0); // Success! |
lrdawg99 | 0:1473318f27b6 | 272 | return 0; |
lrdawg99 | 0:1473318f27b6 | 273 | } |
lrdawg99 | 0:1473318f27b6 | 274 | |
lrdawg99 | 0:1473318f27b6 | 275 | |
lrdawg99 | 0:1473318f27b6 | 276 | // Read a block of data, no command byte, reads length number of bytes and stores it in values. |
lrdawg99 | 0:1473318f27b6 | 277 | int8_t i2c_read_block_data(uint8_t address, uint8_t length, uint8_t *values) |
lrdawg99 | 0:1473318f27b6 | 278 | { |
lrdawg99 | 0:1473318f27b6 | 279 | //uint8_t i = (length-1); |
lrdawg99 | 0:1473318f27b6 | 280 | // int8_t ret = 0; |
lrdawg99 | 0:1473318f27b6 | 281 | // |
lrdawg99 | 0:1473318f27b6 | 282 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 283 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 284 | // ret |= i2c_write((address<<1)|I2C_READ_BIT); //Write 7-bit address with R bit |
lrdawg99 | 0:1473318f27b6 | 285 | // |
lrdawg99 | 0:1473318f27b6 | 286 | // if (ret!=0) //If NACK return 1 |
lrdawg99 | 0:1473318f27b6 | 287 | // { |
lrdawg99 | 0:1473318f27b6 | 288 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 289 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 290 | // } |
lrdawg99 | 0:1473318f27b6 | 291 | // while (i>0) //Begin read loop |
lrdawg99 | 0:1473318f27b6 | 292 | // { |
lrdawg99 | 0:1473318f27b6 | 293 | // values[i] = i2c_read(WITH_ACK); //Read from bus with ACK |
lrdawg99 | 0:1473318f27b6 | 294 | // i--; |
lrdawg99 | 0:1473318f27b6 | 295 | // } |
lrdawg99 | 0:1473318f27b6 | 296 | // |
lrdawg99 | 0:1473318f27b6 | 297 | // values[0] = i2c_read(WITH_NACK); //Read from bus with NACK for the last one; |
lrdawg99 | 0:1473318f27b6 | 298 | // |
lrdawg99 | 0:1473318f27b6 | 299 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 300 | // |
lrdawg99 | 0:1473318f27b6 | 301 | // |
lrdawg99 | 0:1473318f27b6 | 302 | // return(0); // Success! |
lrdawg99 | 0:1473318f27b6 | 303 | return 0; |
lrdawg99 | 0:1473318f27b6 | 304 | } |
lrdawg99 | 0:1473318f27b6 | 305 | |
lrdawg99 | 0:1473318f27b6 | 306 | |
lrdawg99 | 0:1473318f27b6 | 307 | // Write a block of data, starting at register specified by "command" and ending at (command + length - 1) |
lrdawg99 | 0:1473318f27b6 | 308 | int8_t i2c_write_block_data(uint8_t address, uint8_t command, uint8_t length, uint8_t *values) |
lrdawg99 | 0:1473318f27b6 | 309 | { |
lrdawg99 | 0:1473318f27b6 | 310 | // int8_t i = length-1; |
lrdawg99 | 0:1473318f27b6 | 311 | // int8_t ret = 0; |
lrdawg99 | 0:1473318f27b6 | 312 | // |
lrdawg99 | 0:1473318f27b6 | 313 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 314 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 315 | // ret |= i2c_write((address<<1)|I2C_WRITE_BIT); // Write 7 bit address with W bit |
lrdawg99 | 0:1473318f27b6 | 316 | // ret|= i2c_write(command); // Set register to be read to command |
lrdawg99 | 0:1473318f27b6 | 317 | // |
lrdawg99 | 0:1473318f27b6 | 318 | // while (i>=0) |
lrdawg99 | 0:1473318f27b6 | 319 | // { |
lrdawg99 | 0:1473318f27b6 | 320 | // ret|= i2c_write(values[i]); //Write Value |
lrdawg99 | 0:1473318f27b6 | 321 | // i--; |
lrdawg99 | 0:1473318f27b6 | 322 | // } |
lrdawg99 | 0:1473318f27b6 | 323 | // i2c_stop(); // I2C STOP |
lrdawg99 | 0:1473318f27b6 | 324 | // |
lrdawg99 | 0:1473318f27b6 | 325 | // if (ret!=0) |
lrdawg99 | 0:1473318f27b6 | 326 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 327 | // else |
lrdawg99 | 0:1473318f27b6 | 328 | // return(0); // Success! |
lrdawg99 | 0:1473318f27b6 | 329 | return 0; |
lrdawg99 | 0:1473318f27b6 | 330 | } |
lrdawg99 | 0:1473318f27b6 | 331 | |
lrdawg99 | 0:1473318f27b6 | 332 | // Write two command bytes, then receive a block of data |
lrdawg99 | 0:1473318f27b6 | 333 | int8_t i2c_two_byte_command_read_block(uint8_t address, uint16_t command, uint8_t length, uint8_t *values) |
lrdawg99 | 0:1473318f27b6 | 334 | { |
lrdawg99 | 0:1473318f27b6 | 335 | // |
lrdawg99 | 0:1473318f27b6 | 336 | // int8_t ret = 0; |
lrdawg99 | 0:1473318f27b6 | 337 | // |
lrdawg99 | 0:1473318f27b6 | 338 | // union |
lrdawg99 | 0:1473318f27b6 | 339 | // { |
lrdawg99 | 0:1473318f27b6 | 340 | // uint8_t b[2]; |
lrdawg99 | 0:1473318f27b6 | 341 | // uint16_t w; |
lrdawg99 | 0:1473318f27b6 | 342 | // } comm; |
lrdawg99 | 0:1473318f27b6 | 343 | // comm.w = command; |
lrdawg99 | 0:1473318f27b6 | 344 | // |
lrdawg99 | 0:1473318f27b6 | 345 | // uint8_t i = (length-1); |
lrdawg99 | 0:1473318f27b6 | 346 | // |
lrdawg99 | 0:1473318f27b6 | 347 | // |
lrdawg99 | 0:1473318f27b6 | 348 | // if (i2c_start()!=0) //I2C START |
lrdawg99 | 0:1473318f27b6 | 349 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 350 | // ret |= i2c_write((address<<1)|I2C_WRITE_BIT); //Write 7-bit address with W bit |
lrdawg99 | 0:1473318f27b6 | 351 | // ret |= i2c_write(comm.b[1]); //Write MSB command word |
lrdawg99 | 0:1473318f27b6 | 352 | // ret |= i2c_write(comm.b[0]); // Write LSB of command |
lrdawg99 | 0:1473318f27b6 | 353 | // if (i2c_start()!=0) //I2C repeated START |
lrdawg99 | 0:1473318f27b6 | 354 | // { |
lrdawg99 | 0:1473318f27b6 | 355 | // i2c_stop(); //Attempt to issue I2C STOP |
lrdawg99 | 0:1473318f27b6 | 356 | // return(1); //Stop and return 0 if START fail |
lrdawg99 | 0:1473318f27b6 | 357 | // } |
lrdawg99 | 0:1473318f27b6 | 358 | // ret |= i2c_write((address<<1)|I2C_READ_BIT); //Write 7-bit address with R bit |
lrdawg99 | 0:1473318f27b6 | 359 | // if (ret!=0) //If NACK return 1 |
lrdawg99 | 0:1473318f27b6 | 360 | // { |
lrdawg99 | 0:1473318f27b6 | 361 | // i2c_stop(); |
lrdawg99 | 0:1473318f27b6 | 362 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 363 | // } |
lrdawg99 | 0:1473318f27b6 | 364 | // while (i> 0) //Begin read loop |
lrdawg99 | 0:1473318f27b6 | 365 | // { |
lrdawg99 | 0:1473318f27b6 | 366 | // values[i] = i2c_read(WITH_ACK); //Read from bus with ACK |
lrdawg99 | 0:1473318f27b6 | 367 | // i--; |
lrdawg99 | 0:1473318f27b6 | 368 | // } |
lrdawg99 | 0:1473318f27b6 | 369 | // |
lrdawg99 | 0:1473318f27b6 | 370 | // values[0] = i2c_read(WITH_NACK); //Read from bus with NACK for the last one; |
lrdawg99 | 0:1473318f27b6 | 371 | // i2c_stop(); //I2C STOP |
lrdawg99 | 0:1473318f27b6 | 372 | // |
lrdawg99 | 0:1473318f27b6 | 373 | // |
lrdawg99 | 0:1473318f27b6 | 374 | // return(0); // Success! |
lrdawg99 | 0:1473318f27b6 | 375 | return 0; |
lrdawg99 | 0:1473318f27b6 | 376 | } |
lrdawg99 | 0:1473318f27b6 | 377 | |
lrdawg99 | 0:1473318f27b6 | 378 | // Initializes Linduino I2C port. |
lrdawg99 | 0:1473318f27b6 | 379 | // Before communicating to the I2C port throught the QuikEval connector, you must also run |
lrdawg99 | 0:1473318f27b6 | 380 | // quikeval_I2C_connect to connect the I2C port to the QuikEval connector throught the |
lrdawg99 | 0:1473318f27b6 | 381 | // QuikEval MUX (and disconnect SPI). |
lrdawg99 | 0:1473318f27b6 | 382 | void quikeval_I2C_init(void) |
lrdawg99 | 0:1473318f27b6 | 383 | { |
lrdawg99 | 0:1473318f27b6 | 384 | // i2c_enable(); //! 1) Enable the I2C port; |
lrdawg99 | 0:1473318f27b6 | 385 | } |
lrdawg99 | 0:1473318f27b6 | 386 | |
lrdawg99 | 0:1473318f27b6 | 387 | // Switch MUX to connect I2C pins to QuikEval connector. |
lrdawg99 | 0:1473318f27b6 | 388 | // This will disconnect SPI pins. |
lrdawg99 | 0:1473318f27b6 | 389 | void quikeval_I2C_connect(void) |
lrdawg99 | 0:1473318f27b6 | 390 | { |
lrdawg99 | 0:1473318f27b6 | 391 | //// Enable I2C |
lrdawg99 | 0:1473318f27b6 | 392 | // pinMode(QUIKEVAL_MUX_MODE_PIN, OUTPUT); //! 1) Set Mux pin as an output |
lrdawg99 | 0:1473318f27b6 | 393 | // if (digitalRead(QUIKEVAL_MUX_MODE_PIN) == LOW) //! 2) If pin is already high, do nothing |
lrdawg99 | 0:1473318f27b6 | 394 | // { |
lrdawg99 | 0:1473318f27b6 | 395 | // digitalWrite(QUIKEVAL_MUX_MODE_PIN, HIGH); //! 3) Set the Mux pin to high |
lrdawg99 | 0:1473318f27b6 | 396 | // delay(55); //! 4) And wait for LTC4315 to connect (required for rev B) |
lrdawg99 | 0:1473318f27b6 | 397 | // } |
lrdawg99 | 0:1473318f27b6 | 398 | } |
lrdawg99 | 0:1473318f27b6 | 399 | |
lrdawg99 | 0:1473318f27b6 | 400 | // Setup the hardware I2C interface. |
lrdawg99 | 0:1473318f27b6 | 401 | // i2c_enable or quikeval_I2C_init must be called before using any of the other I2C routines. |
lrdawg99 | 0:1473318f27b6 | 402 | void i2c_enable() |
lrdawg99 | 0:1473318f27b6 | 403 | { |
lrdawg99 | 0:1473318f27b6 | 404 | // // set these for 100KHz to match the DC590 |
lrdawg99 | 0:1473318f27b6 | 405 | // TWSR = (HARDWARE_I2C_PRESCALER_4 & 0x03); //! 1) set the prescaler bits |
lrdawg99 | 0:1473318f27b6 | 406 | // TWBR = 18; //! 2) set the bit rate |
lrdawg99 | 0:1473318f27b6 | 407 | |
lrdawg99 | 0:1473318f27b6 | 408 | } |
lrdawg99 | 0:1473318f27b6 | 409 | |
lrdawg99 | 0:1473318f27b6 | 410 | |
lrdawg99 | 0:1473318f27b6 | 411 | // Write start bit to the hardware I2C port |
lrdawg99 | 0:1473318f27b6 | 412 | // return 0 if successful, 1 if not successful |
lrdawg99 | 0:1473318f27b6 | 413 | int8_t i2c_start() |
lrdawg99 | 0:1473318f27b6 | 414 | { |
lrdawg99 | 0:1473318f27b6 | 415 | //uint8_t result; |
lrdawg99 | 0:1473318f27b6 | 416 | // uint16_t timeout; |
lrdawg99 | 0:1473318f27b6 | 417 | // TWCR=(1<<TWINT) | (1<<TWSTA) | (1<<TWEN); //! 1) I2C start |
lrdawg99 | 0:1473318f27b6 | 418 | // for (timeout = 0; timeout < HW_I2C_TIMEOUT; timeout++) //! 2) START the timeout loop |
lrdawg99 | 0:1473318f27b6 | 419 | // { |
lrdawg99 | 0:1473318f27b6 | 420 | // _delay_us(1); |
lrdawg99 | 0:1473318f27b6 | 421 | // if (TWCR & (1 << TWINT)) break; //! 3) Check the TWINT bit in TWCR |
lrdawg99 | 0:1473318f27b6 | 422 | // } |
lrdawg99 | 0:1473318f27b6 | 423 | // result=(TWSR & 0xF8); //! 4) Mask the status |
lrdawg99 | 0:1473318f27b6 | 424 | // if ((result == STATUS_START) || (result == STATUS_REPEATED_START)) |
lrdawg99 | 0:1473318f27b6 | 425 | // return(0); //! 5) Return status |
lrdawg99 | 0:1473318f27b6 | 426 | // else |
lrdawg99 | 0:1473318f27b6 | 427 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 428 | return 0; |
lrdawg99 | 0:1473318f27b6 | 429 | } |
lrdawg99 | 0:1473318f27b6 | 430 | |
lrdawg99 | 0:1473318f27b6 | 431 | // Write a repeat start bit to the hardware I2C port |
lrdawg99 | 0:1473318f27b6 | 432 | // return 0 if successful, 1 if not successful |
lrdawg99 | 0:1473318f27b6 | 433 | int8_t i2c_repeated_start() |
lrdawg99 | 0:1473318f27b6 | 434 | { |
lrdawg99 | 0:1473318f27b6 | 435 | //uint8_t result; |
lrdawg99 | 0:1473318f27b6 | 436 | // uint16_t timeout; |
lrdawg99 | 0:1473318f27b6 | 437 | // TWCR=(1<<TWINT) | (1<<TWSTA) | (1<<TWEN); //! 1) I2C repeated start |
lrdawg99 | 0:1473318f27b6 | 438 | // for (timeout = 0; timeout < HW_I2C_TIMEOUT; timeout++) //! 2) START the timeout loop |
lrdawg99 | 0:1473318f27b6 | 439 | // { |
lrdawg99 | 0:1473318f27b6 | 440 | // _delay_us(1); |
lrdawg99 | 0:1473318f27b6 | 441 | // if (TWCR & (1 << TWINT)) break; //! 3) Check the TWINT bit in TWCR |
lrdawg99 | 0:1473318f27b6 | 442 | // } |
lrdawg99 | 0:1473318f27b6 | 443 | // result=(TWSR & 0xF8); //! 4) Mask the status |
lrdawg99 | 0:1473318f27b6 | 444 | // if (result == STATUS_REPEATED_START) |
lrdawg99 | 0:1473318f27b6 | 445 | // return(0); //! 5) Return status |
lrdawg99 | 0:1473318f27b6 | 446 | // else |
lrdawg99 | 0:1473318f27b6 | 447 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 448 | return 0; |
lrdawg99 | 0:1473318f27b6 | 449 | } |
lrdawg99 | 0:1473318f27b6 | 450 | |
lrdawg99 | 0:1473318f27b6 | 451 | // Write stop bit to the hardware I2C port |
lrdawg99 | 0:1473318f27b6 | 452 | void i2c_stop() |
lrdawg99 | 0:1473318f27b6 | 453 | { |
lrdawg99 | 0:1473318f27b6 | 454 | //TWCR=(1<<TWINT) | (1<<TWEN) | (1<<TWSTO); //! 1) I2C stop |
lrdawg99 | 0:1473318f27b6 | 455 | // while (TWCR & (1<<TWSTO)); //! 2) Wait for stop to complete |
lrdawg99 | 0:1473318f27b6 | 456 | } |
lrdawg99 | 0:1473318f27b6 | 457 | |
lrdawg99 | 0:1473318f27b6 | 458 | // Send a data byte to hardware I2C port |
lrdawg99 | 0:1473318f27b6 | 459 | // return 0 if successful, 1 if not successful |
lrdawg99 | 0:1473318f27b6 | 460 | int8_t i2c_write(uint8_t data) |
lrdawg99 | 0:1473318f27b6 | 461 | { |
lrdawg99 | 0:1473318f27b6 | 462 | // uint8_t result; |
lrdawg99 | 0:1473318f27b6 | 463 | // uint16_t timeout; |
lrdawg99 | 0:1473318f27b6 | 464 | // TWDR = data; //! 1) Load data register |
lrdawg99 | 0:1473318f27b6 | 465 | // TWCR =(1<<TWINT) | (1<<TWEN); //! 2) START transaction |
lrdawg99 | 0:1473318f27b6 | 466 | // for (timeout = 0; timeout < HW_I2C_TIMEOUT; timeout++) //! 3) START the timeout loop |
lrdawg99 | 0:1473318f27b6 | 467 | // { |
lrdawg99 | 0:1473318f27b6 | 468 | // _delay_us(1); |
lrdawg99 | 0:1473318f27b6 | 469 | // if (TWCR & (1 << TWINT)) break; //! 4) Check the TWINT bit in TWCR |
lrdawg99 | 0:1473318f27b6 | 470 | // } |
lrdawg99 | 0:1473318f27b6 | 471 | // result=(TWSR & 0xF8); //! 5) Update status |
lrdawg99 | 0:1473318f27b6 | 472 | // // For a generic write, need to consider all three of these cases (processor specific, some may not be this detailed.) |
lrdawg99 | 0:1473318f27b6 | 473 | // if ((result == STATUS_WRITE_ACK) || (result == STATUS_ADDRESS_WRITE_ACK) || (result == STATUS_ADDRESS_READ_ACK)) |
lrdawg99 | 0:1473318f27b6 | 474 | // return(0); //! 6) Return status |
lrdawg99 | 0:1473318f27b6 | 475 | // else |
lrdawg99 | 0:1473318f27b6 | 476 | // return(1); |
lrdawg99 | 0:1473318f27b6 | 477 | return 0; |
lrdawg99 | 0:1473318f27b6 | 478 | } |
lrdawg99 | 0:1473318f27b6 | 479 | |
lrdawg99 | 0:1473318f27b6 | 480 | // Read a data byte from the hardware I2C port. |
lrdawg99 | 0:1473318f27b6 | 481 | // Returns the data byte read. |
lrdawg99 | 0:1473318f27b6 | 482 | uint8_t i2c_read(int8_t ack) |
lrdawg99 | 0:1473318f27b6 | 483 | { |
lrdawg99 | 0:1473318f27b6 | 484 | //uint8_t result; |
lrdawg99 | 0:1473318f27b6 | 485 | // uint8_t return_value = 1; |
lrdawg99 | 0:1473318f27b6 | 486 | // uint16_t timeout; |
lrdawg99 | 0:1473318f27b6 | 487 | // uint8_t data; |
lrdawg99 | 0:1473318f27b6 | 488 | // if (ack == 0) |
lrdawg99 | 0:1473318f27b6 | 489 | // { |
lrdawg99 | 0:1473318f27b6 | 490 | // TWCR=(1<<TWINT) | (1<<TWEN) | (1<<TWEA); //! 1) START transaction with ack |
lrdawg99 | 0:1473318f27b6 | 491 | // for (timeout = 0; timeout < HW_I2C_TIMEOUT; timeout++) //! 2) START timeout loop |
lrdawg99 | 0:1473318f27b6 | 492 | // { |
lrdawg99 | 0:1473318f27b6 | 493 | // _delay_us(1); |
lrdawg99 | 0:1473318f27b6 | 494 | // if (TWCR & (1 << TWINT)) break; //! 3) Check the TWINT bit in TWCR |
lrdawg99 | 0:1473318f27b6 | 495 | // } |
lrdawg99 | 0:1473318f27b6 | 496 | // data = TWDR; //! 4) Get data |
lrdawg99 | 0:1473318f27b6 | 497 | // result = TWSR & 0xF8; //! 5) Update status |
lrdawg99 | 0:1473318f27b6 | 498 | // if (result == STATUS_READ_ACK) return_value = 0; |
lrdawg99 | 0:1473318f27b6 | 499 | // } |
lrdawg99 | 0:1473318f27b6 | 500 | // else |
lrdawg99 | 0:1473318f27b6 | 501 | // { |
lrdawg99 | 0:1473318f27b6 | 502 | // TWCR=(1<<TWINT) | (1<<TWEN); //! 6) START transaction with NACK |
lrdawg99 | 0:1473318f27b6 | 503 | // for (timeout = 0; timeout < HW_I2C_TIMEOUT; timeout++) |
lrdawg99 | 0:1473318f27b6 | 504 | // { |
lrdawg99 | 0:1473318f27b6 | 505 | // _delay_us(1); |
lrdawg99 | 0:1473318f27b6 | 506 | // if (TWCR & (1 << TWINT)) break; //! 7) Check the TWINT bit in TWCR |
lrdawg99 | 0:1473318f27b6 | 507 | // } |
lrdawg99 | 0:1473318f27b6 | 508 | // data = TWDR; //! 8) Get data |
lrdawg99 | 0:1473318f27b6 | 509 | // result = TWSR & 0xF8; //! 9) Update status |
lrdawg99 | 0:1473318f27b6 | 510 | // if (result == STATUS_READ_NACK) return_value = 0; |
lrdawg99 | 0:1473318f27b6 | 511 | // } |
lrdawg99 | 0:1473318f27b6 | 512 | // return(data); |
lrdawg99 | 0:1473318f27b6 | 513 | return 0; |
lrdawg99 | 0:1473318f27b6 | 514 | } |
lrdawg99 | 0:1473318f27b6 | 515 | |
lrdawg99 | 0:1473318f27b6 | 516 | // Poll the I2C port and look for an acknowledge |
lrdawg99 | 0:1473318f27b6 | 517 | // Returns 0 if successful, 1 if not successful |
lrdawg99 | 0:1473318f27b6 | 518 | int8_t i2c_poll(uint8_t i2c_address) |
lrdawg99 | 0:1473318f27b6 | 519 | |
lrdawg99 | 0:1473318f27b6 | 520 | { |
lrdawg99 | 0:1473318f27b6 | 521 | //int8_t ack=0; |
lrdawg99 | 0:1473318f27b6 | 522 | // ack |= i2c_start(); //! 1) I2C start |
lrdawg99 | 0:1473318f27b6 | 523 | // ack |= i2c_write((i2c_address<<1) | I2C_WRITE_BIT); //! 2) I2C address + !write |
lrdawg99 | 0:1473318f27b6 | 524 | // i2c_stop(); //! 3) I2C stop |
lrdawg99 | 0:1473318f27b6 | 525 | // return(ack); //! 4) Return ack status |
lrdawg99 | 0:1473318f27b6 | 526 | return 0; |
lrdawg99 | 0:1473318f27b6 | 527 | } |