ds1775_cpp.cpp

00001 /*******************************************************************************
00002 * Copyright (C) 2019 Maxim Integrated Products, Inc., All Rights Reserved.
00003 *
00004 * Permission is hereby granted, free of charge, to any person obtaining a
00005 * copy of this software and associated documentation files (the "Software"),
00006 * to deal in the Software without restriction, including without limitation
00007 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
00008 * and/or sell copies of the Software, and to permit persons to whom the
00009 * Software is furnished to do so, subject to the following conditions:
00010 *
00011 * The above copyright notice and this permission notice shall be included
00012 * in all copies or substantial portions of the Software.
00013 *
00014 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
00015 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00016 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
00017 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
00018 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
00019 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
00020 * OTHER DEALINGS IN THE SOFTWARE.
00021 *
00022 * Except as contained in this notice, the name of Maxim Integrated
00023 * Products, Inc. shall not be used except as stated in the Maxim Integrated
00024 * Products, Inc. Branding Policy.
00025 *
00026 * The mere transfer of this software does not imply any licenses
00027 * of trade secrets, proprietary technology, copyrights, patents,
00028 * trademarks, maskwork rights, or any other form of intellectual
00029 * property whatsoever. Maxim Integrated Products, Inc. retains all
00030 * ownership rights.
00031 *******************************************************************************
00032 */
00033 #include "ds1775.h"
00034 #include "ds1775_cpp.h"
00035 #include "mbed.h" 
00036 // #include "USBSerial.h"
00037 
00038 /******************************************************************************
00039  *  C++ version for DS1775 driver                                           *
00040  ******************************************************************************
00041  */
00042 
00043 /******************************************************************************/
00044 DS1775::DS1775(I2C &i2c_bus, uint8_t slave_address):
00045 m_i2c(i2c_bus), 
00046 m_write_address(slave_address <<1),
00047 m_read_address ((slave_address << 1) | 1)
00048 {
00049 }
00050  
00051 /******************************************************************************/
00052 DS1775::~DS1775(void) 
00053 {
00054   /** empty block */
00055 }
00056 
00057 /******************************************************************************/
00058 int DS1775::read_cfg_reg(uint8_t *value) 
00059 {
00060     int32_t ret;
00061     char data[1] = {0};
00062     char reg = DS1775_REG_CONFIGURATION;
00063 
00064     /* write to the Register Select, true is for repeated start */
00065     ret = m_i2c.write(m_write_address, &reg, 1, true);
00066     if (ret == 0) {
00067         ret = m_i2c.read(m_read_address, data, 1, false);
00068         if (ret == 0) {
00069             *value = data[0];
00070             return DS1775_NO_ERROR;
00071         } else {
00072             printf(
00073                 "%s: failed to read data: ret: %d\r\n", __func__, ret);
00074             }
00075     } else {                
00076         printf("%s: failed to write to Register Select: ret: %d\r\n",
00077             __func__, ret);
00078     }
00079     return DS1775_ERROR;
00080 }
00081 
00082 /******************************************************************************/
00083 int DS1775::read_reg16(int16_t *value, char reg) 
00084 {
00085     int32_t ret;
00086     char data[2] = {0, 0};
00087     ds1775_raw_data tmp;
00088      
00089     if (reg == DS1775_REG_TEMPERATURE || 
00090         reg == DS1775_REG_THYST_LOW_TRIP || reg == DS1775_REG_TOS_HIGH_TRIP) {
00091         /* write to the Register Select, true is for repeated start */
00092         ret = m_i2c.write(m_write_address, &reg, 1, true);
00093         /* read the two bytes of data */
00094         if (ret == 0) {
00095             ret = m_i2c.read(m_read_address, data, 2, false);
00096             if (ret == 0) {
00097                 tmp.msb = data[0];
00098                 tmp.lsb = data[1];
00099                 *value = tmp.swrd;
00100                 return DS1775_NO_ERROR;
00101             } else {
00102                 printf(
00103                     "%s: failed to read data: ret: %d\r\n", __func__, ret);
00104             }
00105         } else {                
00106             printf("%s: failed to write to Register Select: ret: %d\r\n",
00107                 __func__, ret);
00108         }
00109     } else {
00110         printf("%s: register address is not correct: register: %d\r\n",
00111                 __func__, reg);
00112     }                
00113     return DS1775_ERROR;
00114 }
00115 
00116 /******************************************************************************/
00117 float DS1775::read_reg_as_temperature(uint8_t reg)
00118 {
00119     ds1775_raw_data tmp;
00120     float temperature;
00121     if (reg == DS1775_REG_TEMPERATURE ||
00122         reg == DS1775_REG_THYST_LOW_TRIP || reg == DS1775_REG_TOS_HIGH_TRIP) {
00123         read_reg16(&tmp.swrd, reg);
00124         temperature = (float)tmp.swrd;  /* values are 2's complement */
00125         temperature *= DS1775_CF_LSB;
00126         return temperature;
00127     } else {
00128         printf("%s: register is invalid, %d r\n", __func__, reg);
00129         return 0;
00130     }
00131 }
00132 
00133 /******************************************************************************/
00134 int DS1775::write_reg16(int16_t value, char reg) 
00135 {
00136     int32_t ret;
00137     char cmd[3];
00138     ds1775_raw_data tmp;
00139 
00140     if (reg >= DS1775_REG_THYST_LOW_TRIP && reg <= DS1775_REG_MAX) {
00141         cmd[0] = reg;
00142         tmp.swrd = value;
00143         cmd[1] = tmp.msb;
00144         cmd[2] = tmp.lsb;
00145         ret = m_i2c.write(m_write_address, cmd, 3, false);
00146         if (ret == 0) {
00147             return DS1775_NO_ERROR;
00148         } else {
00149             printf("%s: I2C write error %d\r\n",__func__, ret);
00150             return DS1775_ERROR;
00151         }
00152     } else {
00153         printf("%s: register value invalid %x\r\n",__func__, reg);
00154         return DS1775_ERROR;
00155     }
00156 }
00157 
00158 
00159 /******************************************************************************/
00160 int DS1775::write_cfg_reg(uint8_t cfg)
00161 {
00162     int32_t ret;
00163     char cmd[2];
00164 
00165     cmd[0] = DS1775_REG_CONFIGURATION;
00166     cmd[1] = cfg;
00167     ret = m_i2c.write(m_write_address, cmd, 2, false);
00168     if (ret == 0) {
00169         return DS1775_NO_ERROR;
00170     } else {
00171         printf("%s: I2C write error %d\r\n",__func__, ret);
00172         return DS1775_ERROR;
00173     }
00174 }
00175 
00176 /******************************************************************************/
00177 int DS1775::write_trip_low_thyst(float temperature)
00178 {
00179     ds1775_raw_data raw;
00180     temperature /= DS1775_CF_LSB;
00181     raw.swrd = int16_t(temperature);
00182     return write_reg16(raw.swrd, DS1775_REG_THYST_LOW_TRIP);
00183 }
00184 
00185 /******************************************************************************/
00186 int DS1775::write_trip_high_tos(float temperature)
00187 {
00188     ds1775_raw_data raw;
00189     temperature /= DS1775_CF_LSB;
00190     raw.swrd = int16_t(temperature);
00191     return write_reg16(raw.uwrd, DS1775_REG_TOS_HIGH_TRIP);
00192 }
00193 
00194 /******************************************************************************/
00195 float DS1775::celsius_to_fahrenheit(float temp_c)
00196 {
00197     float temp_f;
00198     temp_f = ((temp_c * 9)/5) + 32;
00199     return temp_f;
00200 }