Davy Van Belle / MAX44009

Maxim MAX44009 Industry's Lowest-Power. Ambient Light Sensor with ADC. http://www.maximintegrated.com/datasheet/index.mvp/id/7175

Dependents:   agr_dist_v2

MAX44009.cpp@0:726b77a319d8, 2013-08-07 (annotated)

Committer:
gizmo69the2nd
Date:
Wed Aug 07 22:45:56 2013 +0000
Revision:
0:726b77a319d8
Final version

Who changed what in which revision?

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gizmo69the2nd 0:726b77a319d8 1 /*
gizmo69the2nd 0:726b77a319d8 2 * MAX44009 Ambient Light Sensor with ADC library
gizmo69the2nd 0:726b77a319d8 3 *
gizmo69the2nd 0:726b77a319d8 4 *
gizmo69the2nd 0:726b77a319d8 5 * Copyright (c) 2013 Davy Van Belle, MIT License
gizmo69the2nd 0:726b77a319d8 6 *
gizmo69the2nd 0:726b77a319d8 7 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
gizmo69the2nd 0:726b77a319d8 8 * and associated documentation files (the "Software"), to deal in the Software without restriction,
gizmo69the2nd 0:726b77a319d8 9 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
gizmo69the2nd 0:726b77a319d8 10 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
gizmo69the2nd 0:726b77a319d8 11 * furnished to do so, subject to the following conditions:
gizmo69the2nd 0:726b77a319d8 12 *
gizmo69the2nd 0:726b77a319d8 13 * The above copyright notice and this permission notice shall be included in all copies or
gizmo69the2nd 0:726b77a319d8 14 * substantial portions of the Software.
gizmo69the2nd 0:726b77a319d8 15 *
gizmo69the2nd 0:726b77a319d8 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
gizmo69the2nd 0:726b77a319d8 17 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
gizmo69the2nd 0:726b77a319d8 18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
gizmo69the2nd 0:726b77a319d8 19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
gizmo69the2nd 0:726b77a319d8 20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
gizmo69the2nd 0:726b77a319d8 21 */
gizmo69the2nd 0:726b77a319d8 22
gizmo69the2nd 0:726b77a319d8 23 /** @file
gizmo69the2nd 0:726b77a319d8 24 * @brief MAX44009 I2C
gizmo69the2nd 0:726b77a319d8 25 */
gizmo69the2nd 0:726b77a319d8 26
gizmo69the2nd 0:726b77a319d8 27 #include "mbed.h"
gizmo69the2nd 0:726b77a319d8 28 #include "MAX44009.h"
gizmo69the2nd 0:726b77a319d8 29
gizmo69the2nd 0:726b77a319d8 30 /** init MAX44009 class
gizmo69the2nd 0:726b77a319d8 31 * @param *i2c pointer to I2C serial interface
gizmo69the2nd 0:726b77a319d8 32 * @param addr sensor I2C address
gizmo69the2nd 0:726b77a319d8 33 */
gizmo69the2nd 0:726b77a319d8 34 MAX44009::MAX44009 (I2C* i2c, char addr)
gizmo69the2nd 0:726b77a319d8 35 {
gizmo69the2nd 0:726b77a319d8 36 _i2c = i2c;
gizmo69the2nd 0:726b77a319d8 37 _addr = addr;
gizmo69the2nd 0:726b77a319d8 38 }
gizmo69the2nd 0:726b77a319d8 39
gizmo69the2nd 0:726b77a319d8 40 /** Set configuration register for the device
gizmo69the2nd 0:726b77a319d8 41 * @param config desired configuration register bits
gizmo69the2nd 0:726b77a319d8 42 * BIT 7 - CONT: 1 = continuous mode, 0 = single measurement
gizmo69the2nd 0:726b77a319d8 43 * BIT 6 - MANUAL: 1 = CDR, TIM[2:0] set by user, 0 = CDR, TIM[2:0] set by internal autorange
gizmo69the2nd 0:726b77a319d8 44 * BIT [5:4] - Not Used
gizmo69the2nd 0:726b77a319d8 45 * BIT 3 - CDR: 1 = Current divided by 8. (High-brightness), 0 = Current not divided.
gizmo69the2nd 0:726b77a319d8 46 * BIT [2:0] - TIM: Integration Time. See datasheet.
gizmo69the2nd 0:726b77a319d8 47 */
gizmo69the2nd 0:726b77a319d8 48
gizmo69the2nd 0:726b77a319d8 49 void MAX44009::setConfig (char config)
gizmo69the2nd 0:726b77a319d8 50 {
gizmo69the2nd 0:726b77a319d8 51 char cmd[2];
gizmo69the2nd 0:726b77a319d8 52 cmd[0] = CONFIG;
gizmo69the2nd 0:726b77a319d8 53 cmd[1] = config;
gizmo69the2nd 0:726b77a319d8 54 _i2c->write(_addr,cmd,2);
gizmo69the2nd 0:726b77a319d8 55 }
gizmo69the2nd 0:726b77a319d8 56
gizmo69the2nd 0:726b77a319d8 57 /** Get device INT_STATUS register
gizmo69the2nd 0:726b77a319d8 58 * BIT 0 : 0 = No interrupt event occurred, 1 = Ambient light intensity is outside the threshold range.
gizmo69the2nd 0:726b77a319d8 59 */
gizmo69the2nd 0:726b77a319d8 60 char MAX44009::getIntStatus()
gizmo69the2nd 0:726b77a319d8 61 {
gizmo69the2nd 0:726b77a319d8 62 char status;
gizmo69the2nd 0:726b77a319d8 63 char cmd = INT_STATUS;
gizmo69the2nd 0:726b77a319d8 64 _i2c->write(_addr,&cmd,1,true);
gizmo69the2nd 0:726b77a319d8 65 _i2c->read(_addr+1,&status,1);
gizmo69the2nd 0:726b77a319d8 66 return status;
gizmo69the2nd 0:726b77a319d8 67 }
gizmo69the2nd 0:726b77a319d8 68
gizmo69the2nd 0:726b77a319d8 69 /** Set device INT_ENABLE register
gizmo69the2nd 0:726b77a319d8 70 * @param Enable BIT 0 : 0 = INT pin and INTS bit not effected if an interrupt event occurred, 1 = INT pin pulled low and INTS bit is set if interrupt occurred. /
gizmo69the2nd 0:726b77a319d8 71 */
gizmo69the2nd 0:726b77a319d8 72 void MAX44009::setIntEnable(bool Enable)
gizmo69the2nd 0:726b77a319d8 73 {
gizmo69the2nd 0:726b77a319d8 74 char cmd[2];
gizmo69the2nd 0:726b77a319d8 75 cmd[0] = INT_ENABLE;
gizmo69the2nd 0:726b77a319d8 76 cmd[1] = 0x00 | Enable;
gizmo69the2nd 0:726b77a319d8 77 _i2c->write(_addr,cmd,2);
gizmo69the2nd 0:726b77a319d8 78 }
gizmo69the2nd 0:726b77a319d8 79
gizmo69the2nd 0:726b77a319d8 80 /** Get LUX reading from ADC
gizmo69the2nd 0:726b77a319d8 81 *
gizmo69the2nd 0:726b77a319d8 82 */
gizmo69the2nd 0:726b77a319d8 83 float MAX44009::getLUXReading()
gizmo69the2nd 0:726b77a319d8 84 {
gizmo69the2nd 0:726b77a319d8 85 char buff[2];
gizmo69the2nd 0:726b77a319d8 86 char cmd[2];
gizmo69the2nd 0:726b77a319d8 87 char expo,mant;
gizmo69the2nd 0:726b77a319d8 88 float lux;
gizmo69the2nd 0:726b77a319d8 89
gizmo69the2nd 0:726b77a319d8 90 cmd[0] = LUX_HIGH_B;
gizmo69the2nd 0:726b77a319d8 91 cmd[1] = LUX_LOW_B;
gizmo69the2nd 0:726b77a319d8 92
gizmo69the2nd 0:726b77a319d8 93 _i2c->write(_addr,&cmd[0],1,true);
gizmo69the2nd 0:726b77a319d8 94 _i2c->read(_addr+1,&buff[0],1,true);
gizmo69the2nd 0:726b77a319d8 95 _i2c->write(_addr,&cmd[1],1,true);
gizmo69the2nd 0:726b77a319d8 96 _i2c->read(_addr+1,&buff[1],1);
gizmo69the2nd 0:726b77a319d8 97
gizmo69the2nd 0:726b77a319d8 98 expo = (buff[0] & 0xF0) >> 4;
gizmo69the2nd 0:726b77a319d8 99 mant = ((buff[0] & 0x0F) << 4) | (buff[1] & 0x0F) ;
gizmo69the2nd 0:726b77a319d8 100
gizmo69the2nd 0:726b77a319d8 101 lux = pow((double)2,(double)expo) * mant * 0.045;
gizmo69the2nd 0:726b77a319d8 102
gizmo69the2nd 0:726b77a319d8 103 return lux;
gizmo69the2nd 0:726b77a319d8 104 }
gizmo69the2nd 0:726b77a319d8 105
gizmo69the2nd 0:726b77a319d8 106 /** Set upper threshold
gizmo69the2nd 0:726b77a319d8 107 * @param threshold set upper threshold value. Further info, see datasheet
gizmo69the2nd 0:726b77a319d8 108 */
gizmo69the2nd 0:726b77a319d8 109 void MAX44009::setUpperThres(char threshold)
gizmo69the2nd 0:726b77a319d8 110 {
gizmo69the2nd 0:726b77a319d8 111 char cmd[2];
gizmo69the2nd 0:726b77a319d8 112 cmd[0] = UP_THRESH_HIGH_B;
gizmo69the2nd 0:726b77a319d8 113 cmd[1] = threshold;
gizmo69the2nd 0:726b77a319d8 114 _i2c->write(_addr,cmd,2);
gizmo69the2nd 0:726b77a319d8 115 }
gizmo69the2nd 0:726b77a319d8 116
gizmo69the2nd 0:726b77a319d8 117 /** Set lower threshold
gizmo69the2nd 0:726b77a319d8 118 * @param threshold set lower threshold value. Further info, see datasheet
gizmo69the2nd 0:726b77a319d8 119 */
gizmo69the2nd 0:726b77a319d8 120 void MAX44009::setLowerThres(char threshold)
gizmo69the2nd 0:726b77a319d8 121 {
gizmo69the2nd 0:726b77a319d8 122 char cmd[2];
gizmo69the2nd 0:726b77a319d8 123 cmd[0] = LOW_THRESH_HIGH_B;
gizmo69the2nd 0:726b77a319d8 124 cmd[1] = threshold;
gizmo69the2nd 0:726b77a319d8 125 _i2c->write(_addr,cmd,2);
gizmo69the2nd 0:726b77a319d8 126 }
gizmo69the2nd 0:726b77a319d8 127
gizmo69the2nd 0:726b77a319d8 128 /** Set Threshold time
gizmo69the2nd 0:726b77a319d8 129 * @param time set time to trigger interrupt if value is below or above threshold value. Further info, see datasheet
gizmo69the2nd 0:726b77a319d8 130 */
gizmo69the2nd 0:726b77a319d8 131 void MAX44009::setThresTimer(char time)
gizmo69the2nd 0:726b77a319d8 132 {
gizmo69the2nd 0:726b77a319d8 133 char cmd[2];
gizmo69the2nd 0:726b77a319d8 134 cmd[0] = THRESH_TIMER;
gizmo69the2nd 0:726b77a319d8 135 cmd[1] = time;
gizmo69the2nd 0:726b77a319d8 136 _i2c->write(_addr,cmd,2);
gizmo69the2nd 0:726b77a319d8 137 }
gizmo69the2nd 0:726b77a319d8 138
gizmo69the2nd 0:726b77a319d8 139 /*
gizmo69the2nd 0:726b77a319d8 140 float operator= (float d)
gizmo69the2nd 0:726b77a319d8 141 {
gizmo69the2nd 0:726b77a319d8 142 return this.getLUXReading();
gizmo69the2nd 0:726b77a319d8 143 }
gizmo69the2nd 0:726b77a319d8 144 */
gizmo69the2nd 0:726b77a319d8 145