Maxim MAX44009 Industry's Lowest-Power. Ambient Light Sensor with ADC. http://www.maximintegrated.com/datasheet/index.mvp/id/7175
Diff: MAX44009.cpp
- Revision:
- 0:726b77a319d8
diff -r 000000000000 -r 726b77a319d8 MAX44009.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MAX44009.cpp Wed Aug 07 22:45:56 2013 +0000 @@ -0,0 +1,145 @@ +/* + * MAX44009 Ambient Light Sensor with ADC library + * + * + * Copyright (c) 2013 Davy Van Belle, MIT License + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of this software + * and associated documentation files (the "Software"), to deal in the Software without restriction, + * including without limitation the rights to use, copy, modify, merge, publish, distribute, + * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or + * substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING + * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +/** @file + * @brief MAX44009 I2C + */ + +#include "mbed.h" +#include "MAX44009.h" + + /** init MAX44009 class + * @param *i2c pointer to I2C serial interface + * @param addr sensor I2C address + */ + MAX44009::MAX44009 (I2C* i2c, char addr) + { + _i2c = i2c; + _addr = addr; + } + + /** Set configuration register for the device + * @param config desired configuration register bits + * BIT 7 - CONT: 1 = continuous mode, 0 = single measurement + * BIT 6 - MANUAL: 1 = CDR, TIM[2:0] set by user, 0 = CDR, TIM[2:0] set by internal autorange + * BIT [5:4] - Not Used + * BIT 3 - CDR: 1 = Current divided by 8. (High-brightness), 0 = Current not divided. + * BIT [2:0] - TIM: Integration Time. See datasheet. + */ + + void MAX44009::setConfig (char config) + { + char cmd[2]; + cmd[0] = CONFIG; + cmd[1] = config; + _i2c->write(_addr,cmd,2); + } + + /** Get device INT_STATUS register + * BIT 0 : 0 = No interrupt event occurred, 1 = Ambient light intensity is outside the threshold range. + */ + char MAX44009::getIntStatus() + { + char status; + char cmd = INT_STATUS; + _i2c->write(_addr,&cmd,1,true); + _i2c->read(_addr+1,&status,1); + return status; + } + + /** Set device INT_ENABLE register + * @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. / + */ + void MAX44009::setIntEnable(bool Enable) + { + char cmd[2]; + cmd[0] = INT_ENABLE; + cmd[1] = 0x00 | Enable; + _i2c->write(_addr,cmd,2); + } + + /** Get LUX reading from ADC + * + */ + float MAX44009::getLUXReading() + { + char buff[2]; + char cmd[2]; + char expo,mant; + float lux; + + cmd[0] = LUX_HIGH_B; + cmd[1] = LUX_LOW_B; + + _i2c->write(_addr,&cmd[0],1,true); + _i2c->read(_addr+1,&buff[0],1,true); + _i2c->write(_addr,&cmd[1],1,true); + _i2c->read(_addr+1,&buff[1],1); + + expo = (buff[0] & 0xF0) >> 4; + mant = ((buff[0] & 0x0F) << 4) | (buff[1] & 0x0F) ; + + lux = pow((double)2,(double)expo) * mant * 0.045; + + return lux; + } + + /** Set upper threshold + * @param threshold set upper threshold value. Further info, see datasheet + */ + void MAX44009::setUpperThres(char threshold) + { + char cmd[2]; + cmd[0] = UP_THRESH_HIGH_B; + cmd[1] = threshold; + _i2c->write(_addr,cmd,2); + } + + /** Set lower threshold + * @param threshold set lower threshold value. Further info, see datasheet + */ + void MAX44009::setLowerThres(char threshold) + { + char cmd[2]; + cmd[0] = LOW_THRESH_HIGH_B; + cmd[1] = threshold; + _i2c->write(_addr,cmd,2); + } + + /** Set Threshold time + * @param time set time to trigger interrupt if value is below or above threshold value. Further info, see datasheet + */ + void MAX44009::setThresTimer(char time) + { + char cmd[2]; + cmd[0] = THRESH_TIMER; + cmd[1] = time; + _i2c->write(_addr,cmd,2); + } + + /* + float operator= (float d) + { + return this.getLUXReading(); + } + */ + \ No newline at end of file