wireless sensor / PHtest

PH test

Fork of LinearAnalogSensors by Penn Electric

LinearTemp.cpp@0:d84ef842074b, 2012-12-23 (annotated)

Committer:
PennElectric
Date:
Sun Dec 23 07:19:15 2012 +0000
Revision:
0:d84ef842074b
Child:
3:c749fbcf2acb
Completed December 2012

Who changed what in which revision?

UserRevisionLine numberNew contents of line
PennElectric 0:d84ef842074b 1 /* Copyright (c) <2012> <P. Patel>, MIT License
PennElectric 0:d84ef842074b 2 *
PennElectric 0:d84ef842074b 3 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
PennElectric 0:d84ef842074b 4 * and associated documentation files (the "Software"), to deal in the Software without restriction,
PennElectric 0:d84ef842074b 5 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
PennElectric 0:d84ef842074b 6 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
PennElectric 0:d84ef842074b 7 * furnished to do so, subject to the following conditions:
PennElectric 0:d84ef842074b 8 *
PennElectric 0:d84ef842074b 9 * The above copyright notice and this permission notice shall be included in all copies or
PennElectric 0:d84ef842074b 10 * substantial portions of the Software.
PennElectric 0:d84ef842074b 11 *
PennElectric 0:d84ef842074b 12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
PennElectric 0:d84ef842074b 13 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
PennElectric 0:d84ef842074b 14 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
PennElectric 0:d84ef842074b 15 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
PennElectric 0:d84ef842074b 16 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
PennElectric 0:d84ef842074b 17 */
PennElectric 0:d84ef842074b 18
PennElectric 0:d84ef842074b 19 // --------------------- Median Filtered Linear Temperature Sensor Reader ----------------------------
PennElectric 0:d84ef842074b 20
PennElectric 0:d84ef842074b 21 #include "LinearTemp.h"
PennElectric 0:d84ef842074b 22 #include "mbed.h"
PennElectric 0:d84ef842074b 23
PennElectric 0:d84ef842074b 24 // Constructor using two calibration points to define linear multiplier and offset
PennElectric 0:d84ef842074b 25 LinearTemp::LinearTemp(PinName pin, float temp1, unsigned short read1, float temp2, unsigned short read2):_pin(pin) {
PennElectric 0:d84ef842074b 26 _temp = 0.0; // Zero the temperature
PennElectric 0:d84ef842074b 27 _multiplier = (temp2 - temp1) / (read2 - read1); // Calculate multiplier as slope
PennElectric 0:d84ef842074b 28 _offset = temp1 - (_multiplier * read1); // Calculate offset
PennElectric 0:d84ef842074b 29 }
PennElectric 0:d84ef842074b 30 // Constructor using user defined multiplier and offset
PennElectric 0:d84ef842074b 31 LinearTemp::LinearTemp(PinName pin, float multiplier, float offset):_pin(pin) {
PennElectric 0:d84ef842074b 32 _temp = 0.0; // Zero the temperature
PennElectric 0:d84ef842074b 33 _multiplier = multiplier; // Set multiplier
PennElectric 0:d84ef842074b 34 _offset = offset; // Set offset
PennElectric 0:d84ef842074b 35 }
PennElectric 0:d84ef842074b 36
PennElectric 0:d84ef842074b 37 // Populates an array with temperature readings, sorts, and returns median
PennElectric 0:d84ef842074b 38 float LinearTemp::readTemp() {
PennElectric 0:d84ef842074b 39 _tempArr[0] = _pin.read_u16();
PennElectric 0:d84ef842074b 40 for (int i = 1; i < 9; i++) {
PennElectric 0:d84ef842074b 41 _tempArr[i] = _pin.read_u16();
PennElectric 0:d84ef842074b 42 unsigned short tmp = _tempArr[i];
PennElectric 0:d84ef842074b 43 int j;
PennElectric 0:d84ef842074b 44 for (j = i - 1; j >= 0; j--) {
PennElectric 0:d84ef842074b 45 if (tmp>=_tempArr[j]) break;
PennElectric 0:d84ef842074b 46 _tempArr[j + 1] = _tempArr[j];
PennElectric 0:d84ef842074b 47 }
PennElectric 0:d84ef842074b 48 _tempArr[j + 1] = tmp;
PennElectric 0:d84ef842074b 49 }
PennElectric 0:d84ef842074b 50 _temp = (_tempArr[4] * _multiplier) + _offset;
PennElectric 0:d84ef842074b 51 return _temp;
PennElectric 0:d84ef842074b 52 }
PennElectric 0:d84ef842074b 53 // Returns last calculated temperature value
PennElectric 0:d84ef842074b 54 float LinearTemp::getTemp() {
PennElectric 0:d84ef842074b 55 return _temp;
PennElectric 0:d84ef842074b 56 }