Analog Devices / mbed-drivers

A collection of Analog Devices drivers for the mbed platform

For additional information check out the mbed page of the Analog Devices wiki: https://wiki.analog.com/resources/tools-software/mbed-drivers-all

libraries/Thermocouple/Thermocouple_core_cpp.txt@33:c3ec596a29c2, 2016-11-07 (annotated)

Committer:
Adrian Suciu
Date:
Mon Nov 07 16:27:12 2016 +0200
Revision:
33:c3ec596a29c2
Added CN0391, CN0396 and CN0397 shields

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Adrian Suciu 33:c3ec596a29c2 1 #include "thermocouple.h"
Adrian Suciu 33:c3ec596a29c2 2
Adrian Suciu 33:c3ec596a29c2 3 // http://srdata.nist.gov/its90/download/allcoeff.tab
Adrian Suciu 33:c3ec596a29c2 4
Adrian Suciu 33:c3ec596a29c2 5 Thermocouple::Thermocouple(){}
Adrian Suciu 33:c3ec596a29c2 6 Thermocouple::~Thermocouple() {}
Adrian Suciu 33:c3ec596a29c2 7
Adrian Suciu 33:c3ec596a29c2 8 float Thermocouple::lookup(const int32_t *lut, float voltage, uint16_t size, int16_t offset) {
Adrian Suciu 33:c3ec596a29c2 9 uint16_t first = 0;
Adrian Suciu 33:c3ec596a29c2 10 uint16_t last = size - 1;
Adrian Suciu 33:c3ec596a29c2 11 uint16_t middle = (first + last) / 2;
Adrian Suciu 33:c3ec596a29c2 12 int32_t integer_voltage = int32_t(voltage*1000);
Adrian Suciu 33:c3ec596a29c2 13 while (first <= last) {
Adrian Suciu 33:c3ec596a29c2 14 if (lut[middle] < integer_voltage)
Adrian Suciu 33:c3ec596a29c2 15 first = middle + 1;
Adrian Suciu 33:c3ec596a29c2 16 else if (lut[middle] == integer_voltage) {
Adrian Suciu 33:c3ec596a29c2 17 return static_cast<float>(middle + offset);
Adrian Suciu 33:c3ec596a29c2 18 } else
Adrian Suciu 33:c3ec596a29c2 19 last = middle - 1;
Adrian Suciu 33:c3ec596a29c2 20
Adrian Suciu 33:c3ec596a29c2 21 middle = (first + last) / 2;
Adrian Suciu 33:c3ec596a29c2 22 }
Adrian Suciu 33:c3ec596a29c2 23 if (first > last)
Adrian Suciu 33:c3ec596a29c2 24 return static_cast<float>(first+offset);
Adrian Suciu 33:c3ec596a29c2 25
Adrian Suciu 33:c3ec596a29c2 26 return 0; // should never get here
Adrian Suciu 33:c3ec596a29c2 27 }
Adrian Suciu 33:c3ec596a29c2 28
Adrian Suciu 33:c3ec596a29c2 29 float Thermocouple::convert(float voltage, const thermocouple_poly_subrange range[], const int n) {
Adrian Suciu 33:c3ec596a29c2 30 int range_id = 0;
Adrian Suciu 33:c3ec596a29c2 31 float temperature=0;
Adrian Suciu 33:c3ec596a29c2 32 for(range_id = 0 ; range_id<n;range_id++)
Adrian Suciu 33:c3ec596a29c2 33 {
Adrian Suciu 33:c3ec596a29c2 34 if(voltage > range[range_id].min_voltage_range && voltage <= range[range_id].max_voltage_range)
Adrian Suciu 33:c3ec596a29c2 35 break;
Adrian Suciu 33:c3ec596a29c2 36 }
Adrian Suciu 33:c3ec596a29c2 37
Adrian Suciu 33:c3ec596a29c2 38 for (int i = 0; i < range[range_id].n; i++) {
Adrian Suciu 33:c3ec596a29c2 39 temperature += (range[range_id].coef[i] * pow(10,range[range_id].power[i])) * pow(voltage, i);
Adrian Suciu 33:c3ec596a29c2 40 }
Adrian Suciu 33:c3ec596a29c2 41 return temperature;
Adrian Suciu 33:c3ec596a29c2 42 }
Adrian Suciu 33:c3ec596a29c2 43