Jurica Resetar / Si7006A20

Library for Silicon Labs Si7006 digital temperature and humidity chip.

Dependents:   acd52832_Humidity_Temp_Example iBeacon acnsensa acnSENSA

Si7006A20.cpp@2:7c3c7db34528, 2017-09-26 (annotated)

Committer:
jurica238814
Date:
Tue Sep 26 12:04:12 2017 +0000
Revision:
2:7c3c7db34528
Parent:
1:155934570c14 
I2C object replaced by I2C reference.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jurica238814 0:cc2c5d49fe63 1 /*******************************************************************************
jurica238814 0:cc2c5d49fe63 2 * Copyright (C) 2015 Maxim Integrated Products, Inc., All Rights Reserved.
jurica238814 0:cc2c5d49fe63 3 *
jurica238814 0:cc2c5d49fe63 4 * Permission is hereby granted, free of charge, to any person obtaining a
jurica238814 0:cc2c5d49fe63 5 * copy of this software and associated documentation files (the "Software"),
jurica238814 0:cc2c5d49fe63 6 * to deal in the Software without restriction, including without limitation
jurica238814 0:cc2c5d49fe63 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
jurica238814 0:cc2c5d49fe63 8 * and/or sell copies of the Software, and to permit persons to whom the
jurica238814 0:cc2c5d49fe63 9 * Software is furnished to do so, subject to the following conditions:
jurica238814 0:cc2c5d49fe63 10 *
jurica238814 0:cc2c5d49fe63 11 * The above copyright notice and this permission notice shall be included
jurica238814 0:cc2c5d49fe63 12 * in all copies or substantial portions of the Software.
jurica238814 0:cc2c5d49fe63 13 *
jurica238814 0:cc2c5d49fe63 14 *
jurica238814 1:155934570c14 15 *******************************************************************************
jurica238814 1:155934570c14 16 */
jurica238814 1:155934570c14 17
jurica238814 1:155934570c14 18 /*
jurica238814 1:155934570c14 19 * The library is modified to suite Si7006A20 Humidity and Temperature Sensor
jurica238814 1:155934570c14 20 * by Jurica Resetar @ aconno
jurica238814 0:cc2c5d49fe63 21 * More info and contact: aconno.de
jurica238814 1:155934570c14 22 * jurica_resetar@yahoo.com
jurica238814 0:cc2c5d49fe63 23 *
jurica238814 0:cc2c5d49fe63 24 */
jurica238814 0:cc2c5d49fe63 25
jurica238814 0:cc2c5d49fe63 26 #include "Si7006A20.h"
jurica238814 1:155934570c14 27 #include "aconno_i2c.h"
jurica238814 0:cc2c5d49fe63 28
jurica238814 1:155934570c14 29 #define TEMPERATURE_DELAY_MS (10)
jurica238814 1:155934570c14 30 #define HUMIDITY_DELAY_MS (20)
jurica238814 0:cc2c5d49fe63 31
jurica238814 1:155934570c14 32 char cmd_meas_humid = 0xE5;
jurica238814 1:155934570c14 33 char cmd_meas_humid_no_hold = 0xF5;
jurica238814 1:155934570c14 34 char cmd_meas_temp = 0xE3;
jurica238814 1:155934570c14 35 char cmd_meas_temp_no_hold = 0xF3;
jurica238814 1:155934570c14 36 char cmd_meas_prev_temp = 0xE0;
jurica238814 1:155934570c14 37 char cmd_rst = 0xFE;
jurica238814 1:155934570c14 38 char cmd_write_user1 = 0xE6;
jurica238814 1:155934570c14 39 char cmd_read_user1 = 0xE7;
jurica238814 1:155934570c14 40 char cmd_id_1[] = {0xFA, 0x0F};
jurica238814 1:155934570c14 41 char cmd_id_2[] = {0xFC, 0xC9};
jurica238814 1:155934570c14 42 char cmd_fw_ver[] = {0x84, 0xB8};
jurica238814 0:cc2c5d49fe63 43
jurica238814 2:7c3c7db34528 44
jurica238814 2:7c3c7db34528 45 Si7006::Si7006(I2C *i2c) : i2c(i2c, char(I2C_ADDR)){
jurica238814 2:7c3c7db34528 46
jurica238814 0:cc2c5d49fe63 47 }
jurica238814 0:cc2c5d49fe63 48
jurica238814 1:155934570c14 49 uint8_t Si7006::getElectronicId(char* id){
jurica238814 1:155934570c14 50 uint8_t success;
jurica238814 1:155934570c14 51
jurica238814 1:155934570c14 52 success = i2c.sendCommand(cmd_id_1, sizeof(cmd_id_1), id, 4);
jurica238814 1:155934570c14 53 success = i2c.sendCommand(cmd_id_2, sizeof(cmd_id_2), (id+4), 4);
jurica238814 1:155934570c14 54
jurica238814 1:155934570c14 55 return success;
jurica238814 0:cc2c5d49fe63 56 }
jurica238814 0:cc2c5d49fe63 57
jurica238814 0:cc2c5d49fe63 58 int Si7006::configResolution(Si7006::resolution_t resolution){
jurica238814 1:155934570c14 59 char data;
jurica238814 1:155934570c14 60
jurica238814 1:155934570c14 61 // Read User1 Register
jurica238814 1:155934570c14 62 i2c.readFromReg(cmd_read_user1, &data, 1);
jurica238814 0:cc2c5d49fe63 63 switch (resolution) {
jurica238814 0:cc2c5d49fe63 64 case RH_12b_TEMP_14b:
jurica238814 1:155934570c14 65 data &= ~0x81;
jurica238814 0:cc2c5d49fe63 66 break;
jurica238814 0:cc2c5d49fe63 67 case RH_8b_TEMP_12b:
jurica238814 1:155934570c14 68 data = (data & ~0x80) | 0x01;
jurica238814 0:cc2c5d49fe63 69 break;
jurica238814 0:cc2c5d49fe63 70 case RH_10b_TEMP_13b:
jurica238814 1:155934570c14 71 data = (data & ~0x01) | 0x80;
jurica238814 0:cc2c5d49fe63 72 break;
jurica238814 0:cc2c5d49fe63 73 case RH_11b_TEMP_11b:
jurica238814 1:155934570c14 74 data |= 0x81;
jurica238814 0:cc2c5d49fe63 75 break;
jurica238814 0:cc2c5d49fe63 76 default:
jurica238814 0:cc2c5d49fe63 77 return -1;
jurica238814 0:cc2c5d49fe63 78 }
jurica238814 0:cc2c5d49fe63 79
jurica238814 1:155934570c14 80 return i2c.writeToReg(cmd_write_user1, &data, 1);
jurica238814 0:cc2c5d49fe63 81 }
jurica238814 0:cc2c5d49fe63 82
jurica238814 1:155934570c14 83 float Si7006::getTemperature(){
jurica238814 1:155934570c14 84 char temper[2];
jurica238814 1:155934570c14 85
jurica238814 1:155934570c14 86 i2c.sendCommand(&cmd_meas_temp_no_hold, sizeof(cmd_meas_temp_no_hold));
jurica238814 1:155934570c14 87 wait_ms(TEMPERATURE_DELAY_MS);
jurica238814 1:155934570c14 88 i2c.readBus(temper, 2);
jurica238814 0:cc2c5d49fe63 89
jurica238814 1:155934570c14 90 return calculateTemperature(temper);
jurica238814 0:cc2c5d49fe63 91 }
jurica238814 0:cc2c5d49fe63 92
jurica238814 1:155934570c14 93 float Si7006::calculateTemperature(char *rawTemp){
jurica238814 1:155934570c14 94 float temperature;
jurica238814 1:155934570c14 95 int16_t code;
jurica238814 0:cc2c5d49fe63 96
jurica238814 1:155934570c14 97 code = (uint16_t)((*(rawTemp+0)<<8) + (*(rawTemp+1)<<0));
jurica238814 1:155934570c14 98 temperature = (((float)175.72 * code) / 65536.0f) - 46.85;
jurica238814 1:155934570c14 99
jurica238814 1:155934570c14 100 //return temperature;
jurica238814 1:155934570c14 101 return temperature;
jurica238814 0:cc2c5d49fe63 102 }
jurica238814 0:cc2c5d49fe63 103
jurica238814 1:155934570c14 104 float Si7006::getHumidity(){
jurica238814 1:155934570c14 105 char humid[2];
jurica238814 1:155934570c14 106
jurica238814 1:155934570c14 107 i2c.sendCommand(&cmd_meas_humid, sizeof(cmd_meas_humid));
jurica238814 1:155934570c14 108 wait_ms(HUMIDITY_DELAY_MS);
jurica238814 1:155934570c14 109 i2c.readBus(humid, 2);
jurica238814 1:155934570c14 110
jurica238814 0:cc2c5d49fe63 111 return checkHumidity(humid);
jurica238814 0:cc2c5d49fe63 112 }
jurica238814 0:cc2c5d49fe63 113
jurica238814 1:155934570c14 114 float Si7006::checkHumidity(char *rawHumidity){
jurica238814 1:155934570c14 115 float humidity;
jurica238814 0:cc2c5d49fe63 116 uint16_t code;
jurica238814 0:cc2c5d49fe63 117
jurica238814 0:cc2c5d49fe63 118 // Get 16-bit value from bytes read
jurica238814 1:155934570c14 119 code = (uint16_t)((*(rawHumidity+0)<<8) + (*(rawHumidity+1)<<0));
jurica238814 0:cc2c5d49fe63 120 // Calculate the humidity using the formula from the datasheet
jurica238814 1:155934570c14 121 humidity = ((((float)125 * code)) / 65536.0f) - 6;
jurica238814 0:cc2c5d49fe63 122
jurica238814 1:155934570c14 123 return humidity;
jurica238814 0:cc2c5d49fe63 124 }
jurica238814 0:cc2c5d49fe63 125
jurica238814 0:cc2c5d49fe63 126 int Si7006::getPrevTemperature(float *tempC) {
jurica238814 1:155934570c14 127 /*
jurica238814 1:155934570c14 128 if (i2c.write(i2cADDR, cmd_meas_prev_temp, sizeof(cmd_meas_prev_temp)) != 0) {
jurica238814 0:cc2c5d49fe63 129 return -1;
jurica238814 0:cc2c5d49fe63 130 }
jurica238814 0:cc2c5d49fe63 131 if(checkTemperature(tempC) != 0) {
jurica238814 0:cc2c5d49fe63 132 return -1;
jurica238814 0:cc2c5d49fe63 133 }
jurica238814 0:cc2c5d49fe63 134 return 0;
jurica238814 1:155934570c14 135 */
jurica238814 0:cc2c5d49fe63 136 }
jurica238814 0:cc2c5d49fe63 137
jurica238814 0:cc2c5d49fe63 138 int Si7006::getPrevTemperature(int16_t *tempCx10) {
jurica238814 1:155934570c14 139 /*
jurica238814 1:155934570c14 140 if (i2c.write(i2cADDR, cmd_meas_prev_temp, sizeof(cmd_meas_prev_temp)) != 0) {
jurica238814 0:cc2c5d49fe63 141 return -1;
jurica238814 0:cc2c5d49fe63 142 }
jurica238814 0:cc2c5d49fe63 143 if(checkTemperature(tempCx10) != 0) {
jurica238814 0:cc2c5d49fe63 144 return -1;
jurica238814 0:cc2c5d49fe63 145 }
jurica238814 0:cc2c5d49fe63 146 return 0;
jurica238814 1:155934570c14 147 */
jurica238814 0:cc2c5d49fe63 148 }
jurica238814 0:cc2c5d49fe63 149
jurica238814 0:cc2c5d49fe63 150 int Si7006::getRev(char *rev){
jurica238814 1:155934570c14 151 /*
jurica238814 1:155934570c14 152 if (i2c.write(i2cADDR, cmd_fw_ver, sizeof(cmd_fw_ver)) != 0) {
jurica238814 0:cc2c5d49fe63 153 return -1;
jurica238814 0:cc2c5d49fe63 154 }
jurica238814 1:155934570c14 155 if (i2c.read(i2cADDR, rev, 1) != 0) {
jurica238814 0:cc2c5d49fe63 156 return -1;
jurica238814 0:cc2c5d49fe63 157 }
jurica238814 0:cc2c5d49fe63 158
jurica238814 0:cc2c5d49fe63 159 return 0;
jurica238814 1:155934570c14 160 */
jurica238814 0:cc2c5d49fe63 161 }
jurica238814 0:cc2c5d49fe63 162
jurica238814 1:155934570c14 163 int Si7006::heater(bool enable){
jurica238814 0:cc2c5d49fe63 164 char data[2];
jurica238814 1:155934570c14 165 /*
jurica238814 1:155934570c14 166 if (i2c.write(i2cADDR, cmd_read_user1, sizeof(cmd_read_user1)) != 0) {
jurica238814 0:cc2c5d49fe63 167 return -1;
jurica238814 0:cc2c5d49fe63 168 }
jurica238814 0:cc2c5d49fe63 169
jurica238814 1:155934570c14 170 if (i2c.read(i2cADDR, &data[1], 1) != 0) {
jurica238814 0:cc2c5d49fe63 171 return -1;
jurica238814 0:cc2c5d49fe63 172 }
jurica238814 0:cc2c5d49fe63 173
jurica238814 0:cc2c5d49fe63 174 if (enable) {
jurica238814 0:cc2c5d49fe63 175 data[1] |= 0x04;
jurica238814 0:cc2c5d49fe63 176 } else {
jurica238814 0:cc2c5d49fe63 177 data[1] &= ~0x04;
jurica238814 0:cc2c5d49fe63 178 }
jurica238814 0:cc2c5d49fe63 179
jurica238814 0:cc2c5d49fe63 180 data[0] = cmd_write_user1[0];
jurica238814 0:cc2c5d49fe63 181
jurica238814 1:155934570c14 182 if (i2c.write(i2cADDR, data, 2) != 0) {
jurica238814 0:cc2c5d49fe63 183 return -1;
jurica238814 0:cc2c5d49fe63 184 }
jurica238814 0:cc2c5d49fe63 185
jurica238814 0:cc2c5d49fe63 186 return 0;
jurica238814 1:155934570c14 187 */
jurica238814 0:cc2c5d49fe63 188 }
jurica238814 0:cc2c5d49fe63 189
jurica238814 1:155934570c14 190 char Si7006::crc8(char value, char seed){
jurica238814 0:cc2c5d49fe63 191 int i;
jurica238814 0:cc2c5d49fe63 192
jurica238814 0:cc2c5d49fe63 193 for (i = 0; i < 8; i++) {
jurica238814 0:cc2c5d49fe63 194
jurica238814 0:cc2c5d49fe63 195 if ((value ^ seed) & 0x80) {
jurica238814 0:cc2c5d49fe63 196 seed <<= 1;
jurica238814 0:cc2c5d49fe63 197 seed ^= POLYVAL;
jurica238814 0:cc2c5d49fe63 198 } else {
jurica238814 0:cc2c5d49fe63 199 seed <<= 1;
jurica238814 0:cc2c5d49fe63 200 }
jurica238814 0:cc2c5d49fe63 201 value <<= 1;
jurica238814 0:cc2c5d49fe63 202 }
jurica238814 0:cc2c5d49fe63 203 return seed;
jurica238814 0:cc2c5d49fe63 204 }