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libraries/CN0357/CN0357.cpp@24:dae7123d432a, 2016-05-18 (annotated)

Committer:
Adrian Suciu
Date:
Wed May 18 16:57:57 2016 +0300
Revision:
24:dae7123d432a
Parent:
11:2e67c719ce37 
Improved compatibility with Linux systems

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Adrian Suciu 11:2e67c719ce37 1 /**
Adrian Suciu 11:2e67c719ce37 2 * @file cn0357.cpp
Adrian Suciu 11:2e67c719ce37 3 * @brief Source file for CN0357
Adrian Suciu 11:2e67c719ce37 4 * @author Analog Devices Inc.
Adrian Suciu 11:2e67c719ce37 5 *
Adrian Suciu 11:2e67c719ce37 6 * For support please go to:
Adrian Suciu 11:2e67c719ce37 7 * Github: https://github.com/analogdevicesinc/mbed-adi
Adrian Suciu 11:2e67c719ce37 8 * Support: https://ez.analog.com/community/linux-device-drivers/microcontroller-no-os-drivers
Adrian Suciu 11:2e67c719ce37 9 * Product: www.analog.com/EVAL-CN0357-ARDZ
Adrian Suciu 11:2e67c719ce37 10 * More: https://wiki.analog.com/resources/tools-software/mbed-drivers-all
Adrian Suciu 11:2e67c719ce37 11
Adrian Suciu 11:2e67c719ce37 12 ********************************************************************************
Adrian Suciu 11:2e67c719ce37 13 * Copyright 2016(c) Analog Devices, Inc.
Adrian Suciu 11:2e67c719ce37 14 *
Adrian Suciu 11:2e67c719ce37 15 * All rights reserved.
Adrian Suciu 11:2e67c719ce37 16 *
Adrian Suciu 11:2e67c719ce37 17 * Redistribution and use in source and binary forms, with or without
Adrian Suciu 11:2e67c719ce37 18 * modification, are permitted provided that the following conditions are met:
Adrian Suciu 11:2e67c719ce37 19 * - Redistributions of source code must retain the above copyright
Adrian Suciu 11:2e67c719ce37 20 * notice, this list of conditions and the following disclaimer.
Adrian Suciu 11:2e67c719ce37 21 * - Redistributions in binary form must reproduce the above copyright
Adrian Suciu 11:2e67c719ce37 22 * notice, this list of conditions and the following disclaimer in
Adrian Suciu 11:2e67c719ce37 23 * the documentation and/or other materials provided with the
Adrian Suciu 11:2e67c719ce37 24 * distribution.
Adrian Suciu 11:2e67c719ce37 25 * - Neither the name of Analog Devices, Inc. nor the names of its
Adrian Suciu 11:2e67c719ce37 26 * contributors may be used to endorse or promote products derived
Adrian Suciu 11:2e67c719ce37 27 * from this software without specific prior written permission.
Adrian Suciu 11:2e67c719ce37 28 * - The use of this software may or may not infringe the patent rights
Adrian Suciu 11:2e67c719ce37 29 * of one or more patent holders. This license does not release you
Adrian Suciu 11:2e67c719ce37 30 * from the requirement that you obtain separate licenses from these
Adrian Suciu 11:2e67c719ce37 31 * patent holders to use this software.
Adrian Suciu 11:2e67c719ce37 32 * - Use of the software either in source or binary form, must be run
Adrian Suciu 11:2e67c719ce37 33 * on or directly connected to an Analog Devices Inc. component.
Adrian Suciu 11:2e67c719ce37 34 *
Adrian Suciu 11:2e67c719ce37 35 * THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR
Adrian Suciu 11:2e67c719ce37 36 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT,
Adrian Suciu 11:2e67c719ce37 37 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
Adrian Suciu 11:2e67c719ce37 38 * IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT,
Adrian Suciu 11:2e67c719ce37 39 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
Adrian Suciu 11:2e67c719ce37 40 * LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR
Adrian Suciu 11:2e67c719ce37 41 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
Adrian Suciu 11:2e67c719ce37 42 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
Adrian Suciu 11:2e67c719ce37 43 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
Adrian Suciu 11:2e67c719ce37 44 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Adrian Suciu 11:2e67c719ce37 45 *
Adrian Suciu 11:2e67c719ce37 46 ********************************************************************************/
Adrian Suciu 11:2e67c719ce37 47
Adrian Suciu 11:2e67c719ce37 48 #include "mbed.h"
Adrian Suciu 11:2e67c719ce37 49 #include "AD7790.h"
Adrian Suciu 11:2e67c719ce37 50 #include "AD5270.h"
Adrian Suciu 11:2e67c719ce37 51 #include "CN0357.h"
Adrian Suciu 11:2e67c719ce37 52
Adrian Suciu 11:2e67c719ce37 53 /**
Adrian Suciu 11:2e67c719ce37 54 * @brief CN0357 constructor
Adrian Suciu 11:2e67c719ce37 55 * @param CSAD7790 - (optional)chip select of the AD7790
Adrian Suciu 11:2e67c719ce37 56 * @param CSAD5270 - (optional)chip select of the AD5270
Adrian Suciu 11:2e67c719ce37 57 * @param MOSI - (optional)pin of the SPI interface
Adrian Suciu 11:2e67c719ce37 58 * @param MISO - (optional)pin of the SPI interface
Adrian Suciu 11:2e67c719ce37 59 * @param SCK - (optional)pin of the SPI interface
Adrian Suciu 11:2e67c719ce37 60 */
Adrian Suciu 11:2e67c719ce37 61 CN0357::CN0357(PinName CSAD7790, PinName CSAD5270, PinName MOSI, PinName MISO,
Adrian Suciu 11:2e67c719ce37 62 PinName SCK) :
Adrian Suciu 11:2e67c719ce37 63 _vref(1.2), _sensor_sensitivity(0), _sensor_range(0), _RDACvalue(0),
Adrian Suciu 11:2e67c719ce37 64 ad7790(_vref, CSAD7790, MOSI, MISO, SCK), ad5270(CSAD5270, 20000.0, MOSI, MISO, SCK)
Adrian Suciu 11:2e67c719ce37 65
Adrian Suciu 11:2e67c719ce37 66 {
Adrian Suciu 11:2e67c719ce37 67 }
Adrian Suciu 11:2e67c719ce37 68
Adrian Suciu 11:2e67c719ce37 69 /**
Adrian Suciu 11:2e67c719ce37 70 * @brief initializes the AD7790 and the AD5270
Adrian Suciu 11:2e67c719ce37 71 * @param range - range of the sensor used (in ppm)
Adrian Suciu 11:2e67c719ce37 72 * @param sensitivity - sensitivity of the sensor (A/ppm)
Adrian Suciu 11:2e67c719ce37 73 * @param jp - (optional)jumper configuration of the CN0357
Adrian Suciu 11:2e67c719ce37 74 * @param mode_val - (optional)if jp is set to InternalADC, configures the mode register of the Internal ADC
Adrian Suciu 11:2e67c719ce37 75 * @param filter_val - (optional)if jp is set to InternalADC, configures the filter register of the Internal ADC
Adrian Suciu 11:2e67c719ce37 76 */
Adrian Suciu 11:2e67c719ce37 77 void CN0357::init(float range, float sensitivity, JumperConfig_t jp, uint8_t mode_val, uint8_t filter_val)
Adrian Suciu 11:2e67c719ce37 78 {
Adrian Suciu 11:2e67c719ce37 79 ad5270.frequency(500000);
Adrian Suciu 11:2e67c719ce37 80 ad7790.frequency(500000);
Adrian Suciu 11:2e67c719ce37 81
Adrian Suciu 11:2e67c719ce37 82 float resistance = set_sensor_parameters(range, sensitivity);
Adrian Suciu 11:2e67c719ce37 83
Adrian Suciu 11:2e67c719ce37 84 if(jp == INTERNAL_AD7790) {
Adrian Suciu 11:2e67c719ce37 85 _AD7790_init(mode_val, filter_val);
Adrian Suciu 11:2e67c719ce37 86 }
Adrian Suciu 11:2e67c719ce37 87 _rdac_init(resistance);
Adrian Suciu 11:2e67c719ce37 88 }
Adrian Suciu 11:2e67c719ce37 89
Adrian Suciu 11:2e67c719ce37 90 /**
Adrian Suciu 11:2e67c719ce37 91 * @brief initializes the RDAC and sets SDO to HiZ
Adrian Suciu 11:2e67c719ce37 92 * @param resistance - resistance value to initialize the RDAC
Adrian Suciu 11:2e67c719ce37 93 * @return
Adrian Suciu 11:2e67c719ce37 94 */
Adrian Suciu 11:2e67c719ce37 95 void CN0357::_rdac_init(float resistance)
Adrian Suciu 11:2e67c719ce37 96 {
Adrian Suciu 11:2e67c719ce37 97 /* RDAC initialization*/
Adrian Suciu 11:2e67c719ce37 98 /* Compute for the nearest RDAC value from given resistance and save data to the structure */
Adrian Suciu 11:2e67c719ce37 99 set_RDAC_value(resistance);
Adrian Suciu 11:2e67c719ce37 100 /* Set AD5270 SDO to Hi-Z */
Adrian Suciu 11:2e67c719ce37 101 ad5270.set_SDO_HiZ();
Adrian Suciu 11:2e67c719ce37 102 }
Adrian Suciu 11:2e67c719ce37 103
Adrian Suciu 11:2e67c719ce37 104 /**
Adrian Suciu 11:2e67c719ce37 105 * @brief initializes the AD7790
Adrian Suciu 11:2e67c719ce37 106 * @param mode_val - configures the mode register of the Internal ADC
Adrian Suciu 11:2e67c719ce37 107 * @param filter_val - configures the filter register of the Internal ADC
Adrian Suciu 11:2e67c719ce37 108 */
Adrian Suciu 11:2e67c719ce37 109 void CN0357::_AD7790_init(uint8_t mode_val, uint8_t filter_val)
Adrian Suciu 11:2e67c719ce37 110 {
Adrian Suciu 11:2e67c719ce37 111 ad7790.reset();
Adrian Suciu 11:2e67c719ce37 112 wait_ms(50);
Adrian Suciu 11:2e67c719ce37 113
Adrian Suciu 11:2e67c719ce37 114 ad7790.write_mode_reg(mode_val);
Adrian Suciu 11:2e67c719ce37 115 wait_us(2);
Adrian Suciu 11:2e67c719ce37 116
Adrian Suciu 11:2e67c719ce37 117 ad7790.write_filter_reg(filter_val);
Adrian Suciu 11:2e67c719ce37 118 wait_ms(50);
Adrian Suciu 11:2e67c719ce37 119 }
Adrian Suciu 11:2e67c719ce37 120
Adrian Suciu 11:2e67c719ce37 121 /**
Adrian Suciu 11:2e67c719ce37 122 * @brief reads the status register of the AD7790
Adrian Suciu 11:2e67c719ce37 123 * @return status register value
Adrian Suciu 11:2e67c719ce37 124 */
Adrian Suciu 11:2e67c719ce37 125 uint8_t CN0357::read_adc_status(void)
Adrian Suciu 11:2e67c719ce37 126 {
Adrian Suciu 11:2e67c719ce37 127 return ad7790.read_status_reg();
Adrian Suciu 11:2e67c719ce37 128 }
Adrian Suciu 11:2e67c719ce37 129
Adrian Suciu 11:2e67c719ce37 130 /**
Adrian Suciu 11:2e67c719ce37 131 * @brief reads the ADC and computes the sensor voltage
Adrian Suciu 11:2e67c719ce37 132 * @return sensor voltage
Adrian Suciu 11:2e67c719ce37 133 */
Adrian Suciu 11:2e67c719ce37 134 float CN0357::read_sensor_voltage(void)
Adrian Suciu 11:2e67c719ce37 135 {
Adrian Suciu 11:2e67c719ce37 136 return ad7790.read_voltage();
Adrian Suciu 11:2e67c719ce37 137 }
Adrian Suciu 11:2e67c719ce37 138
Adrian Suciu 11:2e67c719ce37 139 /**
Adrian Suciu 11:2e67c719ce37 140 * @brief reads the data register of the AD7790
Adrian Suciu 11:2e67c719ce37 141 * @return data register value
Adrian Suciu 11:2e67c719ce37 142 */
Adrian Suciu 11:2e67c719ce37 143 uint16_t CN0357::read_sensor(void)
Adrian Suciu 11:2e67c719ce37 144 {
Adrian Suciu 11:2e67c719ce37 145 return ad7790.read_u16();
Adrian Suciu 11:2e67c719ce37 146 }
Adrian Suciu 11:2e67c719ce37 147
Adrian Suciu 11:2e67c719ce37 148 /**
Adrian Suciu 11:2e67c719ce37 149 * @brief reads and computes the sensor reading in PPM
Adrian Suciu 11:2e67c719ce37 150 * @return value of the sensor reading in PPM
Adrian Suciu 11:2e67c719ce37 151 */
Adrian Suciu 11:2e67c719ce37 152 float CN0357::read_ppm()
Adrian Suciu 11:2e67c719ce37 153 {
Adrian Suciu 11:2e67c719ce37 154 return calc_ppm(ad7790.read_voltage()); /* Convert voltage to Gas concentration*/
Adrian Suciu 11:2e67c719ce37 155 }
Adrian Suciu 11:2e67c719ce37 156
Adrian Suciu 11:2e67c719ce37 157 /**
Adrian Suciu 11:2e67c719ce37 158 * @brief computes a value in PPM from a reading received as a param
Adrian Suciu 11:2e67c719ce37 159 * @param adcVoltage - voltage to be converted to PPM
Adrian Suciu 11:2e67c719ce37 160 * @return sensor value in PPM
Adrian Suciu 11:2e67c719ce37 161 */
Adrian Suciu 11:2e67c719ce37 162 float CN0357::calc_ppm(float adcVoltage)
Adrian Suciu 11:2e67c719ce37 163 {
Adrian Suciu 11:2e67c719ce37 164 float fConcentration = 0;
Adrian Suciu 11:2e67c719ce37 165 fConcentration = (fabs(adcVoltage) / _RDACvalue) / _sensor_sensitivity;
Adrian Suciu 11:2e67c719ce37 166 return fConcentration;
Adrian Suciu 11:2e67c719ce37 167 }
Adrian Suciu 11:2e67c719ce37 168
Adrian Suciu 11:2e67c719ce37 169 /**
Adrian Suciu 11:2e67c719ce37 170 * @brief computes voltage from a 16 bit ADC value received as a parameter
Adrian Suciu 11:2e67c719ce37 171 * @param data - ADC value
Adrian Suciu 11:2e67c719ce37 172 * @return sensor voltage
Adrian Suciu 11:2e67c719ce37 173 */
Adrian Suciu 11:2e67c719ce37 174 float CN0357::data_to_voltage(uint16_t data)
Adrian Suciu 11:2e67c719ce37 175 {
Adrian Suciu 11:2e67c719ce37 176 return ad7790.data_to_voltage(data);
Adrian Suciu 11:2e67c719ce37 177 }
Adrian Suciu 11:2e67c719ce37 178
Adrian Suciu 11:2e67c719ce37 179 /**
Adrian Suciu 11:2e67c719ce37 180 * @brief sets a new value for the RDAC
Adrian Suciu 11:2e67c719ce37 181 * @param resistance new value for the resistance
Adrian Suciu 11:2e67c719ce37 182 * @return none
Adrian Suciu 11:2e67c719ce37 183 */
Adrian Suciu 11:2e67c719ce37 184 void CN0357::set_RDAC_value(float resistance)
Adrian Suciu 11:2e67c719ce37 185 {
Adrian Suciu 11:2e67c719ce37 186 _RDACvalue = ad5270.write_RDAC(resistance);
Adrian Suciu 11:2e67c719ce37 187 }
Adrian Suciu 11:2e67c719ce37 188
Adrian Suciu 11:2e67c719ce37 189 /**
Adrian Suciu 11:2e67c719ce37 190 * @brief getter method for RDAC value
Adrian Suciu 11:2e67c719ce37 191 * @return value of the RDAC in ohms
Adrian Suciu 11:2e67c719ce37 192 */
Adrian Suciu 11:2e67c719ce37 193 float CN0357::get_RDAC_value()
Adrian Suciu 11:2e67c719ce37 194 {
Adrian Suciu 11:2e67c719ce37 195 return _RDACvalue;
Adrian Suciu 11:2e67c719ce37 196 }
Adrian Suciu 11:2e67c719ce37 197
Adrian Suciu 11:2e67c719ce37 198 /**
Adrian Suciu 11:2e67c719ce37 199 * @brief set sensor range and sensitivity
Adrian Suciu 11:2e67c719ce37 200 * sets sensor range, sensitivity
Adrian Suciu 11:2e67c719ce37 201 * returns suggested resistance value for feedback resistor
Adrian Suciu 11:2e67c719ce37 202 * @param range - range of the sensor used (in ppm)
Adrian Suciu 11:2e67c719ce37 203 * @param sensitivity - sensitivity of the sensor (in A/ppm)
Adrian Suciu 11:2e67c719ce37 204 * @return suggested resistance value for feedback resistor
Adrian Suciu 11:2e67c719ce37 205 */
Adrian Suciu 11:2e67c719ce37 206 float CN0357::set_sensor_parameters(float range, float sensitivity)
Adrian Suciu 11:2e67c719ce37 207 {
Adrian Suciu 11:2e67c719ce37 208 _sensor_sensitivity = static_cast<float>(sensitivity);
Adrian Suciu 11:2e67c719ce37 209 _sensor_range = range;
Adrian Suciu 11:2e67c719ce37 210 return (_vref / (static_cast<float>(_sensor_range * _sensor_sensitivity)));
Adrian Suciu 11:2e67c719ce37 211 }
Adrian Suciu 11:2e67c719ce37 212
Adrian Suciu 11:2e67c719ce37 213 /**
Adrian Suciu 11:2e67c719ce37 214 * @brief getter method for sensor sensitivity
Adrian Suciu 11:2e67c719ce37 215 * @return sensor sensitivity (in A/ppm)
Adrian Suciu 11:2e67c719ce37 216 */
Adrian Suciu 11:2e67c719ce37 217 float CN0357::get_sensor_sensitivity()
Adrian Suciu 11:2e67c719ce37 218 {
Adrian Suciu 11:2e67c719ce37 219 return _sensor_sensitivity;
Adrian Suciu 11:2e67c719ce37 220 }
Adrian Suciu 11:2e67c719ce37 221
Adrian Suciu 11:2e67c719ce37 222 /**
Adrian Suciu 11:2e67c719ce37 223 * @brief getter method for sensor range
Adrian Suciu 11:2e67c719ce37 224 * @return sensor range (in ppm)
Adrian Suciu 11:2e67c719ce37 225 */
Adrian Suciu 11:2e67c719ce37 226 float CN0357::get_sensor_range()
Adrian Suciu 11:2e67c719ce37 227 {
Adrian Suciu 11:2e67c719ce37 228 return _sensor_range;
Adrian Suciu 11:2e67c719ce37 229 }