MAX44009 Ambient Light Sensor with ADC library
Fork of MAX44009 by
MAX44009.cpp
- Committer:
- lucian@192-168-0-103.rdsnet.ro
- Date:
- 2018-02-19
- Revision:
- 3:b3745ae13d09
- Parent:
- 2:7aa4718b2e2b
- Child:
- 4:1799f106738d
File content as of revision 3:b3745ae13d09:
/* * 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] = (char) 0x00 | Enable; _i2c->write(_addr, cmd, 2); } /** * Get raw reading over I2C * @param buff raw reading buffer */ void MAX44009::getRawReading(char buff[2]) { char cmd[2]; 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); } /** * Get LUX reading from ADC */ double MAX44009::getLUXReading() { char buff[2]; this->getRawReading(buff); return this->getLuxFromBuffReading(buff); } /** * Get the computed lux value for given buff reading */ double MAX44009::getLuxFromBuffReading(char *buff) { char exponent, mantissa; double lux; exponent = (char) (buff[0] & 0xF0) >> 4; mantissa = (char) (((buff[0] & 0x0F) << 4) | (buff[1] & 0x0F)); lux = pow((double) 2, (double) exponent) * mantissa * 0.045; return lux; } /** * Set upper threshold * @param threshold set upper threshold value. Further info, see datasheet */ void MAX44009::setUpperThreshold(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::setLowerThreshold(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::setThresholdTimer(char time) { char cmd[2]; cmd[0] = THRESH_TIMER; cmd[1] = time; _i2c->write(_addr, cmd, 2); }