Brian Pearson / SHTx

Humidity and Temperature Sensor - Sensirion SHT1x driver

Dependents:   lpc4088Sensor

Fork of SHTx by Roy van Dam

i2c.hpp@2:189a7d9ddc40, 2016-05-06 (annotated)

Committer:
BPPearson
Date:
Fri May 06 10:17:08 2016 +0000
Revision:
2:189a7d9ddc40
Parent:
1:8465801be23f 
First revision - Melbourne specifics

Who changed what in which revision?

UserRevisionLine numberNew contents of line
NegativeBlack 1:8465801be23f 1 /**
NegativeBlack 1:8465801be23f 2 * Copyright (c) 2010 Roy van Dam <roy@negative-black.org>
NegativeBlack 1:8465801be23f 3 * All rights reserved.
NegativeBlack 1:8465801be23f 4 *
NegativeBlack 1:8465801be23f 5 * Redistribution and use in source and binary forms, with or without
NegativeBlack 1:8465801be23f 6 * modification, are permitted provided that the following conditions
NegativeBlack 1:8465801be23f 7 * are met:
NegativeBlack 1:8465801be23f 8 * 1. Redistributions of source code must retain the above copyright
NegativeBlack 1:8465801be23f 9 * notice, this list of conditions and the following disclaimer.
NegativeBlack 1:8465801be23f 10 * 2. Redistributions in binary form must reproduce the above copyright
NegativeBlack 1:8465801be23f 11 * notice, this list of conditions and the following disclaimer in the
NegativeBlack 1:8465801be23f 12 * documentation and/or other materials provided with the distribution.
NegativeBlack 1:8465801be23f 13 *
NegativeBlack 1:8465801be23f 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
NegativeBlack 1:8465801be23f 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
NegativeBlack 1:8465801be23f 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
NegativeBlack 1:8465801be23f 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
NegativeBlack 1:8465801be23f 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
NegativeBlack 1:8465801be23f 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
NegativeBlack 1:8465801be23f 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
NegativeBlack 1:8465801be23f 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
NegativeBlack 1:8465801be23f 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
NegativeBlack 1:8465801be23f 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
NegativeBlack 1:8465801be23f 24 * SUCH DAMAGE.
NegativeBlack 1:8465801be23f 25 */
NegativeBlack 1:8465801be23f 26
NegativeBlack 1:8465801be23f 27 #ifndef _I2C_HPP_
NegativeBlack 1:8465801be23f 28 #define _I2C_HPP_
NegativeBlack 1:8465801be23f 29
NegativeBlack 1:8465801be23f 30 #include "mbed.h"
NegativeBlack 1:8465801be23f 31
NegativeBlack 1:8465801be23f 32 namespace SHTx {
NegativeBlack 1:8465801be23f 33 /**
NegativeBlack 1:8465801be23f 34 * Class: I2C
NegativeBlack 1:8465801be23f 35 * Humidity and Temperature Sensor - SHT15
NegativeBlack 1:8465801be23f 36 * I2C Bit-bang master driver.
NegativeBlack 1:8465801be23f 37 */
NegativeBlack 1:8465801be23f 38 class I2C {
NegativeBlack 1:8465801be23f 39 private:
NegativeBlack 1:8465801be23f 40 DigitalInOut scl_pin;
NegativeBlack 1:8465801be23f 41 DigitalInOut sda_pin;
NegativeBlack 1:8465801be23f 42
NegativeBlack 1:8465801be23f 43 uint32_t frequency;
NegativeBlack 1:8465801be23f 44
NegativeBlack 1:8465801be23f 45 public:
NegativeBlack 1:8465801be23f 46 /**
NegativeBlack 1:8465801be23f 47 * Constructor: SHTx::I2C
NegativeBlack 1:8465801be23f 48 * Create an I2C Master interface, connected to the specified pins.
NegativeBlack 1:8465801be23f 49 * Bit-bang I2C driver to get around the lousy I2C implementation in the
NegativeBlack 1:8465801be23f 50 * SHTx interface...
NegativeBlack 1:8465801be23f 51 *
NegativeBlack 1:8465801be23f 52 * Variables:
NegativeBlack 1:8465801be23f 53 * sda - I2C data line pin
NegativeBlack 1:8465801be23f 54 * scl - I2C clock line pin
NegativeBlack 1:8465801be23f 55 */
NegativeBlack 1:8465801be23f 56 I2C(PinName sda, PinName scl);
NegativeBlack 1:8465801be23f 57
NegativeBlack 1:8465801be23f 58 /**
NegativeBlack 1:8465801be23f 59 * Function: setFrequency
NegativeBlack 1:8465801be23f 60 * Set the frequency of the SHTx::I2C interface
NegativeBlack 1:8465801be23f 61 *
NegativeBlack 1:8465801be23f 62 * Variables:
NegativeBlack 1:8465801be23f 63 * hz - The bus frequency in hertz
NegativeBlack 1:8465801be23f 64 */
NegativeBlack 1:8465801be23f 65 void setFrequency(uint32_t hz);
NegativeBlack 1:8465801be23f 66
NegativeBlack 1:8465801be23f 67 /**
NegativeBlack 1:8465801be23f 68 * Function: start
NegativeBlack 1:8465801be23f 69 * Issue start condition on the SHTx::I2C bus
NegativeBlack 1:8465801be23f 70 */
NegativeBlack 1:8465801be23f 71 void start(void);
NegativeBlack 1:8465801be23f 72
NegativeBlack 1:8465801be23f 73 /**
NegativeBlack 1:8465801be23f 74 * Function: stop
NegativeBlack 1:8465801be23f 75 * Issue stop condition on the SHTx::I2C bus
NegativeBlack 1:8465801be23f 76 */
NegativeBlack 1:8465801be23f 77 void stop(void);
NegativeBlack 1:8465801be23f 78
NegativeBlack 1:8465801be23f 79 /**
NegativeBlack 1:8465801be23f 80 * Function: wait
NegativeBlack 1:8465801be23f 81 * Wait for SHT15 to complete measurement.
NegativeBlack 1:8465801be23f 82 * Max timeout 500ms.
NegativeBlack 1:8465801be23f 83 *
NegativeBlack 1:8465801be23f 84 * Variables:
NegativeBlack 1:8465801be23f 85 * returns - true if an ACK was received, false otherwise
NegativeBlack 1:8465801be23f 86 */
NegativeBlack 1:8465801be23f 87 bool wait(void);
NegativeBlack 1:8465801be23f 88
NegativeBlack 1:8465801be23f 89 /**
NegativeBlack 1:8465801be23f 90 * Function: reset
NegativeBlack 1:8465801be23f 91 * If communication with the device is lost
NegativeBlack 1:8465801be23f 92 * the command will reset the serial interface
NegativeBlack 1:8465801be23f 93 */
NegativeBlack 1:8465801be23f 94 void reset(void);
NegativeBlack 1:8465801be23f 95
NegativeBlack 1:8465801be23f 96 /**
NegativeBlack 1:8465801be23f 97 * Function: write
NegativeBlack 1:8465801be23f 98 * Write single byte out on the SHTx::I2C bus
NegativeBlack 1:8465801be23f 99 *
NegativeBlack 1:8465801be23f 100 * Variables:
NegativeBlack 1:8465801be23f 101 * data - data to write out on bus
NegativeBlack 1:8465801be23f 102 * returns - true if an ACK was received, false otherwise
NegativeBlack 1:8465801be23f 103 */
NegativeBlack 1:8465801be23f 104 bool write(uint8_t data);
NegativeBlack 1:8465801be23f 105
NegativeBlack 1:8465801be23f 106 /**
NegativeBlack 1:8465801be23f 107 * Function: write
NegativeBlack 1:8465801be23f 108 * Read single byte form the I2C bus
NegativeBlack 1:8465801be23f 109 *
NegativeBlack 1:8465801be23f 110 * Variables:
NegativeBlack 1:8465801be23f 111 * ack - indicates if the byte is to be acknowledged
NegativeBlack 1:8465801be23f 112 * returns - the read byte
NegativeBlack 1:8465801be23f 113 */
NegativeBlack 1:8465801be23f 114 uint8_t read(bool ack);
NegativeBlack 1:8465801be23f 115
NegativeBlack 1:8465801be23f 116 private:
NegativeBlack 1:8465801be23f 117 /**
NegativeBlack 1:8465801be23f 118 * Function: output
NegativeBlack 1:8465801be23f 119 * Configures sda pin as output
NegativeBlack 1:8465801be23f 120 */
NegativeBlack 1:8465801be23f 121 void output(void);
NegativeBlack 1:8465801be23f 122
NegativeBlack 1:8465801be23f 123 /**
NegativeBlack 1:8465801be23f 124 * Function: input
NegativeBlack 1:8465801be23f 125 * Configures sda pin as input
NegativeBlack 1:8465801be23f 126 */
NegativeBlack 1:8465801be23f 127 void input(void);
NegativeBlack 1:8465801be23f 128
NegativeBlack 1:8465801be23f 129 /**
NegativeBlack 1:8465801be23f 130 * Function: sda
NegativeBlack 1:8465801be23f 131 * Drive sda pin.
NegativeBlack 1:8465801be23f 132 *
NegativeBlack 1:8465801be23f 133 * Variables:
NegativeBlack 1:8465801be23f 134 * value - drive pin high or low
NegativeBlack 1:8465801be23f 135 */
NegativeBlack 1:8465801be23f 136 void sda(bool value);
NegativeBlack 1:8465801be23f 137
NegativeBlack 1:8465801be23f 138 /**
NegativeBlack 1:8465801be23f 139 * Function: scl
NegativeBlack 1:8465801be23f 140 * Drive scl pin.
NegativeBlack 1:8465801be23f 141 *
NegativeBlack 1:8465801be23f 142 * Variables:
NegativeBlack 1:8465801be23f 143 * value - drive pin high or low
NegativeBlack 1:8465801be23f 144 */
NegativeBlack 1:8465801be23f 145 void scl(bool value);
NegativeBlack 1:8465801be23f 146
NegativeBlack 1:8465801be23f 147 /**
NegativeBlack 1:8465801be23f 148 * Function: shift_out
NegativeBlack 1:8465801be23f 149 * Write single bit out on the SHTx::I2C bus
NegativeBlack 1:8465801be23f 150 *
NegativeBlack 1:8465801be23f 151 * Variables:
NegativeBlack 1:8465801be23f 152 * bit - value of the bit to be written.
NegativeBlack 1:8465801be23f 153 */
NegativeBlack 1:8465801be23f 154 void shift_out(bool bit);
NegativeBlack 1:8465801be23f 155
NegativeBlack 1:8465801be23f 156 /**
NegativeBlack 1:8465801be23f 157 * Function: shift_in
NegativeBlack 1:8465801be23f 158 * Read single bit from the SHTx::I2C bus
NegativeBlack 1:8465801be23f 159 *
NegativeBlack 1:8465801be23f 160 * Variables:
NegativeBlack 1:8465801be23f 161 * return - value of the bit read.
NegativeBlack 1:8465801be23f 162 */
NegativeBlack 1:8465801be23f 163 bool shift_in(void);
NegativeBlack 1:8465801be23f 164 };
NegativeBlack 1:8465801be23f 165 }
NegativeBlack 1:8465801be23f 166
NegativeBlack 1:8465801be23f 167 /* !_I2C_HPP_ */
NegativeBlack 0:d55659b0c4a0 168 #endif