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.

Diff: DS7505.cpp

Revision:
32:0a09505a656d
Parent:
21:b43e2f7bea6f
--- a/DS7505.cpp	Tue Apr 04 14:10:48 2017 -0500
+++ b/DS7505.cpp	Mon Nov 06 17:34:13 2017 -0600
@@ -28,205 +28,178 @@
 * trademarks, maskwork rights, or any other form of intellectual
 * property whatsoever. Maxim Integrated Products, Inc. retains all
 * ownership rights.
-*******************************************************************************
-*/
+*******************************************************************************/
 
+#include <I2C.h>
+#include <wait_api.h>
 #include "DS7505.hpp"
-#include "I2C.h"
-#include "wait_api.h"
 
-#define I2C_WRITE 0
-#define I2C_READ 1
-
-static const int I2C_WRITE_OK = 1;
+static const int I2C_Write_Ok = 1;
 static const uint8_t DS7505_Config_SD_Bit = 0x01; // Enable shutdown mode
 
 DS7505::DS7505(mbed::I2C & I2C_interface, uint8_t I2C_address)
-  : m_current_config(Config_9b_Res, true), m_I2C_interface(I2C_interface), m_I2C_address(I2C_address)
-{
-  
-}
+    : m_current_config(Config_9b_Res, true), m_I2C_interface(I2C_interface),
+      m_I2C_address(I2C_address) {}
 
-uint8_t DS7505::get_measure_delay_ms(Config_Resolution resolution)
-{
+uint8_t DS7505::get_measure_delay_ms(Config_Resolution resolution) {
   uint8_t measure_delay_ms;
-  
-  switch (resolution)
-  {
-    case Config_9b_Res:
-      measure_delay_ms = 25;
-      break;
-    case Config_10b_Res:
-      measure_delay_ms = 50;
-      break;
-    case Config_11b_Res:
-      measure_delay_ms = 100;
-      break;
-    case Config_12b_Res:
-      measure_delay_ms = 200;
-      break;
-    default:
-      measure_delay_ms = 0;
-      break;
+
+  switch (resolution) {
+  case Config_9b_Res:
+    measure_delay_ms = 25;
+    break;
+  case Config_10b_Res:
+    measure_delay_ms = 50;
+    break;
+  case Config_11b_Res:
+    measure_delay_ms = 100;
+    break;
+  case Config_12b_Res:
+    measure_delay_ms = 200;
+    break;
+  default:
+    measure_delay_ms = 0;
+    break;
   }
-  
+
   return measure_delay_ms;
 }
 
-bool DS7505::read_temp_sensor_data(uint16_t & sensor_data) const
-{
+bool DS7505::read_temp_sensor_data(uint16_t & sensor_data) const {
   bool result;
   uint8_t upperByte, lowerByte;
   int sub_res;
-  
+
   sensor_data = 0;
   m_I2C_interface.start();
-  sub_res = m_I2C_interface.write(m_I2C_address | I2C_READ);
-  if (sub_res == I2C_WRITE_OK)
-  {
+  sub_res = m_I2C_interface.write(m_I2C_address | 1);
+  if (sub_res == I2C_Write_Ok) {
     upperByte = m_I2C_interface.read(mbed::I2C::ACK);
     lowerByte = m_I2C_interface.read(mbed::I2C::NoACK);
   }
   m_I2C_interface.stop();
-  if (sub_res == I2C_WRITE_OK)
-  {
+  if (sub_res == I2C_Write_Ok) {
     sensor_data = ((((uint16_t)upperByte) << 8) | lowerByte);
     result = true;
-  }
-  else
-  {
+  } else {
     // Handle hardware malfunction
     result = false;
   }
-  
+
   return result;
 }
 
-bool DS7505::set_register_pointer(Register pointer_reg) const
-{
+bool DS7505::set_register_pointer(Register pointer_reg) const {
   int res;
-  
+
   m_I2C_interface.start();
-  res = m_I2C_interface.write(m_I2C_address | I2C_WRITE);
-  if (res == I2C_WRITE_OK)
-  {
+  res = m_I2C_interface.write(m_I2C_address);
+  if (res == I2C_Write_Ok) {
     res = m_I2C_interface.write(pointer_reg);
   }
   m_I2C_interface.stop();
-  
-  return (res == I2C_WRITE_OK);
+
+  return (res == I2C_Write_Ok);
 }
 
-bool DS7505::write_register(Register write_reg, uint8_t write_val) const
-{
+bool DS7505::write_register(Register write_reg, uint8_t write_val) const {
   bool res;
-  
+
   m_I2C_interface.start();
-  res = m_I2C_interface.write(m_I2C_address | I2C_WRITE);
-  if (res == I2C_WRITE_OK)
-  {
+  res = m_I2C_interface.write(m_I2C_address);
+  if (res == I2C_Write_Ok) {
     res = m_I2C_interface.write(write_reg);
-    if (res == I2C_WRITE_OK)
+    if (res == I2C_Write_Ok)
       res = m_I2C_interface.write(write_val);
   }
   m_I2C_interface.stop();
-  
-  return (res == I2C_WRITE_OK);
+
+  return (res == I2C_Write_Ok);
 }
 
-bool DS7505::write_current_config() const
-{
+bool DS7505::write_current_config() const {
   uint8_t DS7505_Config_Val = m_current_config.resolution;
   if (m_current_config.enable_shutdown_mode)
     DS7505_Config_Val |= DS7505_Config_SD_Bit;
   return write_register(Configuration_Reg, DS7505_Config_Val);
 }
 
-DS7505::Result DS7505::set_resolution(uint8_t resolution)
-{   
-  switch (resolution)
-  {
-    case 1:
-      m_current_config.resolution = Config_9b_Res;
-      break;
-    case 2:
-      m_current_config.resolution = Config_10b_Res;
-      break;
-    case 3:
-      m_current_config.resolution = Config_11b_Res;
-      break;
-    case 4:
-      m_current_config.resolution = Config_12b_Res;
-      break;
-    default:
-      return Out_of_Range;
+DS7505::Result DS7505::set_resolution(uint8_t resolution) {
+  switch (resolution) {
+  case 1:
+    m_current_config.resolution = Config_9b_Res;
+    break;
+  case 2:
+    m_current_config.resolution = Config_10b_Res;
+    break;
+  case 3:
+    m_current_config.resolution = Config_11b_Res;
+    break;
+  case 4:
+    m_current_config.resolution = Config_12b_Res;
+    break;
+  default:
+    return Out_of_Range;
   }
-  
+
   // Write DS7505 configuration
-  if (!write_current_config())
-  {
+  if (!write_current_config()) {
     // Handle hardware malfunction
     return Hardware_Failure;
   }
-  
+
   // Set pointer to temperature register
-  if (!set_register_pointer(Temperature_Reg))
-  {
+  if (!set_register_pointer(Temperature_Reg)) {
     // Handle hardware malfunction
     return Hardware_Failure;
   }
-  
+
   return Success;
 }
 
-DS7505::Result DS7505::read_temp_sensor(uint16_t & sensor_data) const
-{
+DS7505::Result DS7505::read_temp_sensor(uint16_t & sensor_data) const {
   bool res;
-  
-  if (m_current_config.enable_shutdown_mode)
-  {
+
+  if (m_current_config.enable_shutdown_mode) {
     // Disable shutdown mode
     m_current_config.enable_shutdown_mode = false;
     res = write_current_config();
     if (!res)
       return Hardware_Failure;
-  
+
     // DS7505 measures temperature
-  
+
     // Enable shutdown mode
     m_current_config.enable_shutdown_mode = true;
     res = write_current_config();
     if (!res)
       return Hardware_Failure;
-    
+
     // Set pointer to temperature register
     res = set_register_pointer(Temperature_Reg);
     if (!res)
       return Hardware_Failure;
-    
+
     // Sleep for maximum time needed for sample
     wait_ms(get_measure_delay_ms(m_current_config.resolution));
   }
   // else: shutdown mode disabled
   //    DS7505 is constantly measuring temperature
-  
+
   // Read temperature from sensor
-  if (!read_temp_sensor_data(sensor_data))
-  {
+  if (!read_temp_sensor_data(sensor_data)) {
     return Hardware_Failure;
   }
-  
+
   return Success;
 }
 
-DS7505::Result DS7505::read_current_temp(int16_t & temperature) const
-{
+DS7505::Result DS7505::read_current_temp(int16_t & temperature) const {
   uint16_t sensor_data;
   Result result;
-  
+
   result = read_temp_sensor(sensor_data);
-  if (result == Success)
-  {
+  if (result == Success) {
     // Convert temperature to have an exponent of 10^-2
     temperature = ((int8_t)(sensor_data >> 8)) * 100;
     if (sensor_data & 0x0080)
@@ -241,14 +214,12 @@
   return result;
 }
 
-DS7505::Result DS7505::read_current_temp(double & temperature) const
-{
+DS7505::Result DS7505::read_current_temp(double & temperature) const {
   uint16_t sensor_data;
   Result result;
-  
+
   result = read_temp_sensor(sensor_data);
-  if (result == Success)
-  {
+  if (result == Success) {
     // Convert sensor data to floating-point temperature
     temperature = ((int8_t)(sensor_data >> 8));
     if (sensor_data & 0x0080)
@@ -263,14 +234,12 @@
   return result;
 }
 
-DS7505::Result DS7505::read_current_temp(int8_t & temperature) const
-{
+DS7505::Result DS7505::read_current_temp(int8_t & temperature) const {
   uint16_t sensor_data;
   Result result;
-  
+
   result = read_temp_sensor(sensor_data);
-  if (result == Success)
-  {
+  if (result == Success) {
     // Convert sensor data to integer temperature
     temperature = ((int8_t)(sensor_data >> 8));
   }