Maxim Integrated / Mbed 2 deprecated DeepCover Embedded Security in IoT

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?

UserRevisionLine numberNew 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.
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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 }