Home | History | Annotate | Download | only in maxds3231m 
      1 /*
      2  * Author: Yevgeniy Kiveisha <yevgeniy.kiveisha (at) intel.com>
      3  * Copyright (c) 2014 Intel Corporation.
      4  *
      5  * Permission is hereby granted, free of charge, to any person obtaining
      6  * a copy of this software and associated documentation files (the
      7  * "Software"), to deal in the Software without restriction, including
      8  * without limitation the rights to use, copy, modify, merge, publish,
      9  * distribute, sublicense, and/or sell copies of the Software, and to
     10  * permit persons to whom the Software is furnished to do so, subject to
     11  * the following conditions:
     12  *
     13  * The above copyright notice and this permission notice shall be
     14  * included in all copies or substantial portions of the Software.
     15  *
     16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     19  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
     20  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
     21  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
     22  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     23  */
     24 
     25 #include <iostream>
     26 #include <unistd.h>
     27 #include <stdlib.h>
     28 #include <stdexcept>
     29 
     30 #include "maxds3231m.h"
     31 
     32 using namespace upm;
     33 
     34 MAXDS3231M::MAXDS3231M (int bus, int devAddr) : m_i2Ctx(bus) {
     35     m_name = "MAXDS3231M";
     36 
     37     m_i2cAddr = devAddr;
     38     m_bus = bus;
     39 
     40     mraa::Result ret = m_i2Ctx.address(m_i2cAddr);
     41     if (ret != mraa::SUCCESS) {
     42         throw std::invalid_argument(std::string(__FUNCTION__) +
     43                                     ": m_i2Ctx.address() failed");
     44     }
     45 }
     46 
     47 void
     48 MAXDS3231M::setDate (Time3231 &time) {
     49     uint8_t *data = (uint8_t *)&time;
     50 
     51     i2cWriteReg_N (TIME_CAL_ADDR, 7, data);
     52 }
     53 
     54 bool
     55 MAXDS3231M::getDate (Time3231 &time) {
     56     uint8_t buffer[7];
     57 
     58     // We need 7 bytes of data.
     59     if (i2cReadReg_N (TIME_CAL_ADDR, 7, buffer) > 6) {
     60         uint8_t century = (buffer[5] & 0x80) >> 7;
     61 
     62         time.second     = BCDtoDEC(buffer[0]);
     63         time.minute     = BCDtoDEC(buffer[1]);
     64         time.hour       = BCDtoDEC(buffer[2]);
     65         time.day        = BCDtoDEC(buffer[4]);
     66         time.month      = BCDtoDEC(buffer[5] & 0x1F);
     67         time.year       = (century == 1) ? 2000 + BCDtoDEC(buffer[6]) : 1900 + BCDtoDEC(buffer[6]);
     68         time.weekDay    = BCDtoDEC(buffer[3]);
     69 
     70         return true;
     71     }
     72 
     73     return false;
     74 }
     75 
     76 uint16_t
     77 MAXDS3231M::getTemperature () {
     78     uint8_t     buffer[2];
     79     uint8_t     msb     = 0;
     80     uint8_t     lsb     = 0;
     81 
     82     i2cReadReg_N (TEMPERATURE_ADDR, 2, buffer);
     83     msb = buffer[0];
     84     lsb = buffer[1] >> 6;
     85 
     86     if ((msb & 0x80) != 0)
     87         msb |= ~((1 << 8) - 1); // if negative get two's complement
     88 
     89     return 0.25 * lsb + msb;
     90 }
     91 
     92 /*
     93  * **************
     94  *  private area
     95  * **************
     96  */
     97 uint16_t
     98 MAXDS3231M::i2cReadReg_N (int reg, unsigned int len, uint8_t * buffer) {
     99     int readByte = 0;
    100 
    101     m_i2Ctx.address(m_i2cAddr);
    102     m_i2Ctx.writeByte(reg);
    103 
    104     m_i2Ctx.address(m_i2cAddr);
    105     readByte = m_i2Ctx.read(buffer, len);
    106     return readByte;
    107 }
    108 
    109 mraa::Result
    110 MAXDS3231M::i2cWriteReg_N (uint8_t reg, unsigned int len, uint8_t * buffer) {
    111     mraa::Result error = mraa::SUCCESS;
    112 
    113     error = m_i2Ctx.address (m_i2cAddr);
    114     error = m_i2Ctx.write (buffer, len);
    115 
    116     return error;
    117 }
    118 
    119 uint8_t
    120 MAXDS3231M::DECtoBSD(uint8_t data) {
    121     return ((data / 10 * 16) + (data % 10));
    122 }
    123 
    124 uint8_t
    125 MAXDS3231M::BCDtoDEC(uint8_t data) {
    126     return ((data / 16 * 10) + (data % 16));
    127 }
    128