MAXREFDES143#: DeepCover Embedded Security in IoT Authenticated Sensing & Notification
Dependencies: MaximInterface mbed
The MAXREFDES143# is an Internet of Things (IoT) embedded security reference design, built to protect an industrial sensing node by means of authentication and notification to a web server. The hardware includes a peripheral module representing a protected sensor node monitoring operating temperature and remaining life of a filter (simulated through ambient light sensing) and an mbed shield representing a controller node responsible for monitoring one or more sensor nodes. The design is hierarchical with each controller node communicating data from connected sensor nodes to a web server that maintains a centralized log and dispatches notifications as necessary. The mbed shield contains a Wi-Fi module, a DS2465 coprocessor with 1-Wire® master function, an LCD, LEDs, and pushbuttons. The protected sensor node contains a DS28E15 authenticator, a DS7505 temperature sensor, and a MAX44009 light sensor. The mbed shield communicates to a web server by the onboard Wi-Fi module and to the protected sensor node with I2C and 1-Wire. The MAXREFDES143# is equipped with a standard shield connector for immediate testing using an mbed board such as the MAX32600MBED#. The simplicity of this design enables rapid integration into any star-topology IoT network requiring the heightened security with low overhead provided by the SHA-256 symmetric-key algorithm.
More information about the MAXREFDES143# is available on the Maxim Integrated website.
DS7505.cpp@35:3d414ba9ab6c, 2018-01-19 (annotated)
- Committer:
- IanBenzMaxim
- Date:
- Fri Jan 19 10:33:16 2018 -0600
- Revision:
- 35:3d414ba9ab6c
- Parent:
- 32:0a09505a656d
Updated MaximInterface revision.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
IanBenzMaxim | 1:e1c7c1c636af | 1 | /******************************************************************************* |
IanBenzMaxim | 1:e1c7c1c636af | 2 | * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved. |
IanBenzMaxim | 1:e1c7c1c636af | 3 | * |
IanBenzMaxim | 1:e1c7c1c636af | 4 | * Permission is hereby granted, free of charge, to any person obtaining a |
IanBenzMaxim | 1:e1c7c1c636af | 5 | * copy of this software and associated documentation files (the "Software"), |
IanBenzMaxim | 1:e1c7c1c636af | 6 | * to deal in the Software without restriction, including without limitation |
IanBenzMaxim | 1:e1c7c1c636af | 7 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
IanBenzMaxim | 1:e1c7c1c636af | 8 | * and/or sell copies of the Software, and to permit persons to whom the |
IanBenzMaxim | 1:e1c7c1c636af | 9 | * Software is furnished to do so, subject to the following conditions: |
IanBenzMaxim | 1:e1c7c1c636af | 10 | * |
IanBenzMaxim | 1:e1c7c1c636af | 11 | * The above copyright notice and this permission notice shall be included |
IanBenzMaxim | 1:e1c7c1c636af | 12 | * in all copies or substantial portions of the Software. |
IanBenzMaxim | 1:e1c7c1c636af | 13 | * |
IanBenzMaxim | 1:e1c7c1c636af | 14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
IanBenzMaxim | 1:e1c7c1c636af | 15 | * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
IanBenzMaxim | 1:e1c7c1c636af | 16 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
IanBenzMaxim | 1:e1c7c1c636af | 17 | * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES |
IanBenzMaxim | 1:e1c7c1c636af | 18 | * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
IanBenzMaxim | 1:e1c7c1c636af | 19 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
IanBenzMaxim | 1:e1c7c1c636af | 20 | * OTHER DEALINGS IN THE SOFTWARE. |
IanBenzMaxim | 1:e1c7c1c636af | 21 | * |
IanBenzMaxim | 1:e1c7c1c636af | 22 | * Except as contained in this notice, the name of Maxim Integrated |
IanBenzMaxim | 1:e1c7c1c636af | 23 | * Products, Inc. shall not be used except as stated in the Maxim Integrated |
IanBenzMaxim | 1:e1c7c1c636af | 24 | * Products, Inc. Branding Policy. |
IanBenzMaxim | 1:e1c7c1c636af | 25 | * |
IanBenzMaxim | 1:e1c7c1c636af | 26 | * The mere transfer of this software does not imply any licenses |
IanBenzMaxim | 1:e1c7c1c636af | 27 | * of trade secrets, proprietary technology, copyrights, patents, |
IanBenzMaxim | 1:e1c7c1c636af | 28 | * trademarks, maskwork rights, or any other form of intellectual |
IanBenzMaxim | 1:e1c7c1c636af | 29 | * property whatsoever. Maxim Integrated Products, Inc. retains all |
IanBenzMaxim | 1:e1c7c1c636af | 30 | * ownership rights. |
IanBenzMaxim | 32:0a09505a656d | 31 | *******************************************************************************/ |
IanBenzMaxim | 1:e1c7c1c636af | 32 | |
IanBenzMaxim | 32:0a09505a656d | 33 | #include <I2C.h> |
IanBenzMaxim | 32:0a09505a656d | 34 | #include <wait_api.h> |
IanBenzMaxim | 1:e1c7c1c636af | 35 | #include "DS7505.hpp" |
IanBenzMaxim | 1:e1c7c1c636af | 36 | |
IanBenzMaxim | 32:0a09505a656d | 37 | static const int I2C_Write_Ok = 1; |
IanBenzMaxim | 1:e1c7c1c636af | 38 | static const uint8_t DS7505_Config_SD_Bit = 0x01; // Enable shutdown mode |
IanBenzMaxim | 1:e1c7c1c636af | 39 | |
IanBenzMaxim | 6:b6bafd0a7013 | 40 | DS7505::DS7505(mbed::I2C & I2C_interface, uint8_t I2C_address) |
IanBenzMaxim | 32:0a09505a656d | 41 | : m_current_config(Config_9b_Res, true), m_I2C_interface(I2C_interface), |
IanBenzMaxim | 32:0a09505a656d | 42 | m_I2C_address(I2C_address) {} |
IanBenzMaxim | 1:e1c7c1c636af | 43 | |
IanBenzMaxim | 32:0a09505a656d | 44 | uint8_t DS7505::get_measure_delay_ms(Config_Resolution resolution) { |
IanBenzMaxim | 1:e1c7c1c636af | 45 | uint8_t measure_delay_ms; |
IanBenzMaxim | 32:0a09505a656d | 46 | |
IanBenzMaxim | 32:0a09505a656d | 47 | switch (resolution) { |
IanBenzMaxim | 32:0a09505a656d | 48 | case Config_9b_Res: |
IanBenzMaxim | 32:0a09505a656d | 49 | measure_delay_ms = 25; |
IanBenzMaxim | 32:0a09505a656d | 50 | break; |
IanBenzMaxim | 32:0a09505a656d | 51 | case Config_10b_Res: |
IanBenzMaxim | 32:0a09505a656d | 52 | measure_delay_ms = 50; |
IanBenzMaxim | 32:0a09505a656d | 53 | break; |
IanBenzMaxim | 32:0a09505a656d | 54 | case Config_11b_Res: |
IanBenzMaxim | 32:0a09505a656d | 55 | measure_delay_ms = 100; |
IanBenzMaxim | 32:0a09505a656d | 56 | break; |
IanBenzMaxim | 32:0a09505a656d | 57 | case Config_12b_Res: |
IanBenzMaxim | 32:0a09505a656d | 58 | measure_delay_ms = 200; |
IanBenzMaxim | 32:0a09505a656d | 59 | break; |
IanBenzMaxim | 32:0a09505a656d | 60 | default: |
IanBenzMaxim | 32:0a09505a656d | 61 | measure_delay_ms = 0; |
IanBenzMaxim | 32:0a09505a656d | 62 | break; |
IanBenzMaxim | 1:e1c7c1c636af | 63 | } |
IanBenzMaxim | 32:0a09505a656d | 64 | |
IanBenzMaxim | 1:e1c7c1c636af | 65 | return measure_delay_ms; |
IanBenzMaxim | 1:e1c7c1c636af | 66 | } |
IanBenzMaxim | 1:e1c7c1c636af | 67 | |
IanBenzMaxim | 32:0a09505a656d | 68 | bool DS7505::read_temp_sensor_data(uint16_t & sensor_data) const { |
IanBenzMaxim | 1:e1c7c1c636af | 69 | bool result; |
IanBenzMaxim | 1:e1c7c1c636af | 70 | uint8_t upperByte, lowerByte; |
IanBenzMaxim | 1:e1c7c1c636af | 71 | int sub_res; |
IanBenzMaxim | 32:0a09505a656d | 72 | |
IanBenzMaxim | 1:e1c7c1c636af | 73 | sensor_data = 0; |
IanBenzMaxim | 1:e1c7c1c636af | 74 | m_I2C_interface.start(); |
IanBenzMaxim | 32:0a09505a656d | 75 | sub_res = m_I2C_interface.write(m_I2C_address | 1); |
IanBenzMaxim | 32:0a09505a656d | 76 | if (sub_res == I2C_Write_Ok) { |
IanBenzMaxim | 6:b6bafd0a7013 | 77 | upperByte = m_I2C_interface.read(mbed::I2C::ACK); |
IanBenzMaxim | 6:b6bafd0a7013 | 78 | lowerByte = m_I2C_interface.read(mbed::I2C::NoACK); |
IanBenzMaxim | 1:e1c7c1c636af | 79 | } |
IanBenzMaxim | 1:e1c7c1c636af | 80 | m_I2C_interface.stop(); |
IanBenzMaxim | 32:0a09505a656d | 81 | if (sub_res == I2C_Write_Ok) { |
IanBenzMaxim | 1:e1c7c1c636af | 82 | sensor_data = ((((uint16_t)upperByte) << 8) | lowerByte); |
IanBenzMaxim | 1:e1c7c1c636af | 83 | result = true; |
IanBenzMaxim | 32:0a09505a656d | 84 | } else { |
IanBenzMaxim | 1:e1c7c1c636af | 85 | // Handle hardware malfunction |
IanBenzMaxim | 1:e1c7c1c636af | 86 | result = false; |
IanBenzMaxim | 1:e1c7c1c636af | 87 | } |
IanBenzMaxim | 32:0a09505a656d | 88 | |
IanBenzMaxim | 1:e1c7c1c636af | 89 | return result; |
IanBenzMaxim | 1:e1c7c1c636af | 90 | } |
IanBenzMaxim | 1:e1c7c1c636af | 91 | |
IanBenzMaxim | 32:0a09505a656d | 92 | bool DS7505::set_register_pointer(Register pointer_reg) const { |
IanBenzMaxim | 1:e1c7c1c636af | 93 | int res; |
IanBenzMaxim | 32:0a09505a656d | 94 | |
IanBenzMaxim | 1:e1c7c1c636af | 95 | m_I2C_interface.start(); |
IanBenzMaxim | 32:0a09505a656d | 96 | res = m_I2C_interface.write(m_I2C_address); |
IanBenzMaxim | 32:0a09505a656d | 97 | if (res == I2C_Write_Ok) { |
IanBenzMaxim | 1:e1c7c1c636af | 98 | res = m_I2C_interface.write(pointer_reg); |
IanBenzMaxim | 1:e1c7c1c636af | 99 | } |
IanBenzMaxim | 1:e1c7c1c636af | 100 | m_I2C_interface.stop(); |
IanBenzMaxim | 32:0a09505a656d | 101 | |
IanBenzMaxim | 32:0a09505a656d | 102 | return (res == I2C_Write_Ok); |
IanBenzMaxim | 1:e1c7c1c636af | 103 | } |
IanBenzMaxim | 1:e1c7c1c636af | 104 | |
IanBenzMaxim | 32:0a09505a656d | 105 | bool DS7505::write_register(Register write_reg, uint8_t write_val) const { |
IanBenzMaxim | 1:e1c7c1c636af | 106 | bool res; |
IanBenzMaxim | 32:0a09505a656d | 107 | |
IanBenzMaxim | 1:e1c7c1c636af | 108 | m_I2C_interface.start(); |
IanBenzMaxim | 32:0a09505a656d | 109 | res = m_I2C_interface.write(m_I2C_address); |
IanBenzMaxim | 32:0a09505a656d | 110 | if (res == I2C_Write_Ok) { |
IanBenzMaxim | 1:e1c7c1c636af | 111 | res = m_I2C_interface.write(write_reg); |
IanBenzMaxim | 32:0a09505a656d | 112 | if (res == I2C_Write_Ok) |
IanBenzMaxim | 1:e1c7c1c636af | 113 | res = m_I2C_interface.write(write_val); |
IanBenzMaxim | 1:e1c7c1c636af | 114 | } |
IanBenzMaxim | 1:e1c7c1c636af | 115 | m_I2C_interface.stop(); |
IanBenzMaxim | 32:0a09505a656d | 116 | |
IanBenzMaxim | 32:0a09505a656d | 117 | return (res == I2C_Write_Ok); |
IanBenzMaxim | 1:e1c7c1c636af | 118 | } |
IanBenzMaxim | 1:e1c7c1c636af | 119 | |
IanBenzMaxim | 32:0a09505a656d | 120 | bool DS7505::write_current_config() const { |
IanBenzMaxim | 1:e1c7c1c636af | 121 | uint8_t DS7505_Config_Val = m_current_config.resolution; |
IanBenzMaxim | 1:e1c7c1c636af | 122 | if (m_current_config.enable_shutdown_mode) |
IanBenzMaxim | 1:e1c7c1c636af | 123 | DS7505_Config_Val |= DS7505_Config_SD_Bit; |
IanBenzMaxim | 1:e1c7c1c636af | 124 | return write_register(Configuration_Reg, DS7505_Config_Val); |
IanBenzMaxim | 1:e1c7c1c636af | 125 | } |
IanBenzMaxim | 1:e1c7c1c636af | 126 | |
IanBenzMaxim | 32:0a09505a656d | 127 | DS7505::Result DS7505::set_resolution(uint8_t resolution) { |
IanBenzMaxim | 32:0a09505a656d | 128 | switch (resolution) { |
IanBenzMaxim | 32:0a09505a656d | 129 | case 1: |
IanBenzMaxim | 32:0a09505a656d | 130 | m_current_config.resolution = Config_9b_Res; |
IanBenzMaxim | 32:0a09505a656d | 131 | break; |
IanBenzMaxim | 32:0a09505a656d | 132 | case 2: |
IanBenzMaxim | 32:0a09505a656d | 133 | m_current_config.resolution = Config_10b_Res; |
IanBenzMaxim | 32:0a09505a656d | 134 | break; |
IanBenzMaxim | 32:0a09505a656d | 135 | case 3: |
IanBenzMaxim | 32:0a09505a656d | 136 | m_current_config.resolution = Config_11b_Res; |
IanBenzMaxim | 32:0a09505a656d | 137 | break; |
IanBenzMaxim | 32:0a09505a656d | 138 | case 4: |
IanBenzMaxim | 32:0a09505a656d | 139 | m_current_config.resolution = Config_12b_Res; |
IanBenzMaxim | 32:0a09505a656d | 140 | break; |
IanBenzMaxim | 32:0a09505a656d | 141 | default: |
IanBenzMaxim | 32:0a09505a656d | 142 | return Out_of_Range; |
IanBenzMaxim | 1:e1c7c1c636af | 143 | } |
IanBenzMaxim | 32:0a09505a656d | 144 | |
IanBenzMaxim | 1:e1c7c1c636af | 145 | // Write DS7505 configuration |
IanBenzMaxim | 32:0a09505a656d | 146 | if (!write_current_config()) { |
IanBenzMaxim | 1:e1c7c1c636af | 147 | // Handle hardware malfunction |
IanBenzMaxim | 1:e1c7c1c636af | 148 | return Hardware_Failure; |
IanBenzMaxim | 1:e1c7c1c636af | 149 | } |
IanBenzMaxim | 32:0a09505a656d | 150 | |
IanBenzMaxim | 1:e1c7c1c636af | 151 | // Set pointer to temperature register |
IanBenzMaxim | 32:0a09505a656d | 152 | if (!set_register_pointer(Temperature_Reg)) { |
IanBenzMaxim | 1:e1c7c1c636af | 153 | // Handle hardware malfunction |
IanBenzMaxim | 1:e1c7c1c636af | 154 | return Hardware_Failure; |
IanBenzMaxim | 1:e1c7c1c636af | 155 | } |
IanBenzMaxim | 32:0a09505a656d | 156 | |
IanBenzMaxim | 1:e1c7c1c636af | 157 | return Success; |
IanBenzMaxim | 1:e1c7c1c636af | 158 | } |
IanBenzMaxim | 1:e1c7c1c636af | 159 | |
IanBenzMaxim | 32:0a09505a656d | 160 | DS7505::Result DS7505::read_temp_sensor(uint16_t & sensor_data) const { |
IanBenzMaxim | 1:e1c7c1c636af | 161 | bool res; |
IanBenzMaxim | 32:0a09505a656d | 162 | |
IanBenzMaxim | 32:0a09505a656d | 163 | if (m_current_config.enable_shutdown_mode) { |
IanBenzMaxim | 1:e1c7c1c636af | 164 | // Disable shutdown mode |
IanBenzMaxim | 1:e1c7c1c636af | 165 | m_current_config.enable_shutdown_mode = false; |
IanBenzMaxim | 1:e1c7c1c636af | 166 | res = write_current_config(); |
IanBenzMaxim | 1:e1c7c1c636af | 167 | if (!res) |
IanBenzMaxim | 1:e1c7c1c636af | 168 | return Hardware_Failure; |
IanBenzMaxim | 32:0a09505a656d | 169 | |
IanBenzMaxim | 1:e1c7c1c636af | 170 | // DS7505 measures temperature |
IanBenzMaxim | 32:0a09505a656d | 171 | |
IanBenzMaxim | 1:e1c7c1c636af | 172 | // Enable shutdown mode |
IanBenzMaxim | 1:e1c7c1c636af | 173 | m_current_config.enable_shutdown_mode = true; |
IanBenzMaxim | 1:e1c7c1c636af | 174 | res = write_current_config(); |
IanBenzMaxim | 1:e1c7c1c636af | 175 | if (!res) |
IanBenzMaxim | 1:e1c7c1c636af | 176 | return Hardware_Failure; |
IanBenzMaxim | 32:0a09505a656d | 177 | |
IanBenzMaxim | 1:e1c7c1c636af | 178 | // Set pointer to temperature register |
IanBenzMaxim | 1:e1c7c1c636af | 179 | res = set_register_pointer(Temperature_Reg); |
IanBenzMaxim | 1:e1c7c1c636af | 180 | if (!res) |
IanBenzMaxim | 1:e1c7c1c636af | 181 | return Hardware_Failure; |
IanBenzMaxim | 32:0a09505a656d | 182 | |
IanBenzMaxim | 1:e1c7c1c636af | 183 | // Sleep for maximum time needed for sample |
IanBenzMaxim | 1:e1c7c1c636af | 184 | wait_ms(get_measure_delay_ms(m_current_config.resolution)); |
IanBenzMaxim | 1:e1c7c1c636af | 185 | } |
IanBenzMaxim | 1:e1c7c1c636af | 186 | // else: shutdown mode disabled |
IanBenzMaxim | 1:e1c7c1c636af | 187 | // DS7505 is constantly measuring temperature |
IanBenzMaxim | 32:0a09505a656d | 188 | |
IanBenzMaxim | 1:e1c7c1c636af | 189 | // Read temperature from sensor |
IanBenzMaxim | 32:0a09505a656d | 190 | if (!read_temp_sensor_data(sensor_data)) { |
IanBenzMaxim | 1:e1c7c1c636af | 191 | return Hardware_Failure; |
IanBenzMaxim | 1:e1c7c1c636af | 192 | } |
IanBenzMaxim | 32:0a09505a656d | 193 | |
IanBenzMaxim | 1:e1c7c1c636af | 194 | return Success; |
IanBenzMaxim | 1:e1c7c1c636af | 195 | } |
IanBenzMaxim | 1:e1c7c1c636af | 196 | |
IanBenzMaxim | 32:0a09505a656d | 197 | DS7505::Result DS7505::read_current_temp(int16_t & temperature) const { |
IanBenzMaxim | 1:e1c7c1c636af | 198 | uint16_t sensor_data; |
IanBenzMaxim | 1:e1c7c1c636af | 199 | Result result; |
IanBenzMaxim | 32:0a09505a656d | 200 | |
IanBenzMaxim | 1:e1c7c1c636af | 201 | result = read_temp_sensor(sensor_data); |
IanBenzMaxim | 32:0a09505a656d | 202 | if (result == Success) { |
IanBenzMaxim | 1:e1c7c1c636af | 203 | // Convert temperature to have an exponent of 10^-2 |
IanBenzMaxim | 1:e1c7c1c636af | 204 | temperature = ((int8_t)(sensor_data >> 8)) * 100; |
IanBenzMaxim | 1:e1c7c1c636af | 205 | if (sensor_data & 0x0080) |
IanBenzMaxim | 1:e1c7c1c636af | 206 | temperature += 50; // 0.5 |
IanBenzMaxim | 1:e1c7c1c636af | 207 | if (sensor_data & 0x0040) |
IanBenzMaxim | 1:e1c7c1c636af | 208 | temperature += 25; // 0.25 |
IanBenzMaxim | 1:e1c7c1c636af | 209 | if (sensor_data & 0x0020) |
IanBenzMaxim | 1:e1c7c1c636af | 210 | temperature += 13; // 0.125 |
IanBenzMaxim | 1:e1c7c1c636af | 211 | if (sensor_data & 0x0010) |
IanBenzMaxim | 1:e1c7c1c636af | 212 | temperature += 6; // 0.0625 |
IanBenzMaxim | 1:e1c7c1c636af | 213 | } |
IanBenzMaxim | 1:e1c7c1c636af | 214 | return result; |
IanBenzMaxim | 1:e1c7c1c636af | 215 | } |
IanBenzMaxim | 1:e1c7c1c636af | 216 | |
IanBenzMaxim | 32:0a09505a656d | 217 | DS7505::Result DS7505::read_current_temp(double & temperature) const { |
IanBenzMaxim | 1:e1c7c1c636af | 218 | uint16_t sensor_data; |
IanBenzMaxim | 1:e1c7c1c636af | 219 | Result result; |
IanBenzMaxim | 32:0a09505a656d | 220 | |
IanBenzMaxim | 1:e1c7c1c636af | 221 | result = read_temp_sensor(sensor_data); |
IanBenzMaxim | 32:0a09505a656d | 222 | if (result == Success) { |
IanBenzMaxim | 1:e1c7c1c636af | 223 | // Convert sensor data to floating-point temperature |
IanBenzMaxim | 1:e1c7c1c636af | 224 | temperature = ((int8_t)(sensor_data >> 8)); |
IanBenzMaxim | 1:e1c7c1c636af | 225 | if (sensor_data & 0x0080) |
IanBenzMaxim | 1:e1c7c1c636af | 226 | temperature += 0.5; |
IanBenzMaxim | 1:e1c7c1c636af | 227 | if (sensor_data & 0x0040) |
IanBenzMaxim | 1:e1c7c1c636af | 228 | temperature += 0.25; |
IanBenzMaxim | 1:e1c7c1c636af | 229 | if (sensor_data & 0x0020) |
IanBenzMaxim | 1:e1c7c1c636af | 230 | temperature += 0.125; |
IanBenzMaxim | 1:e1c7c1c636af | 231 | if (sensor_data & 0x0010) |
IanBenzMaxim | 1:e1c7c1c636af | 232 | temperature += 0.0625; |
IanBenzMaxim | 1:e1c7c1c636af | 233 | } |
IanBenzMaxim | 1:e1c7c1c636af | 234 | return result; |
IanBenzMaxim | 1:e1c7c1c636af | 235 | } |
IanBenzMaxim | 1:e1c7c1c636af | 236 | |
IanBenzMaxim | 32:0a09505a656d | 237 | DS7505::Result DS7505::read_current_temp(int8_t & temperature) const { |
IanBenzMaxim | 1:e1c7c1c636af | 238 | uint16_t sensor_data; |
IanBenzMaxim | 1:e1c7c1c636af | 239 | Result result; |
IanBenzMaxim | 32:0a09505a656d | 240 | |
IanBenzMaxim | 1:e1c7c1c636af | 241 | result = read_temp_sensor(sensor_data); |
IanBenzMaxim | 32:0a09505a656d | 242 | if (result == Success) { |
IanBenzMaxim | 1:e1c7c1c636af | 243 | // Convert sensor data to integer temperature |
IanBenzMaxim | 1:e1c7c1c636af | 244 | temperature = ((int8_t)(sensor_data >> 8)); |
IanBenzMaxim | 1:e1c7c1c636af | 245 | } |
IanBenzMaxim | 1:e1c7c1c636af | 246 | return result; |
IanBenzMaxim | 1:e1c7c1c636af | 247 | } |