Embedded system firware written in C against Nordic's NRF SDK. This firmware allows for BLE central to connect. It enables to control and sample the 4 ADC (SAADC) connected to 4 printed sensors. Data are ring-buffered. The code has been developed on Segger Embedded Studio (successful compilations/programming have been made with GNU ARM on earlier versions).

Bluetooth BLE
Controllable Gain (over BLE)
Controllable Sampling Frequency (over BLE)
Automatic Re-pairing
Watchdog reset

Embedded C project for the NRF52 of Nordic

Use nordic NRF5 SDK Developped with Segger Embedded Studio (on Windows 10)

Instructions:

• Download Nordic NRF5 SDK version 15.3.0 (important)
• Download Segger Embedded Studio (latest version)
• Clone the project
• Navigate to : smart_mask/Embedded_system/ble_mask/project/ses/
• Open " on any text editor
• At the bottom of the file, add a configuration (before "") such as this one bellow

    <configuration
        Name="theNameYouWant"
        c_preprocessor_definitions="DEBUG; DEBUG_NRF"
        gcc_optimization_level="None"
        macros="NRF_SDK=C:/absolute/path/to/your/sdk;PROJ_ROOT=C:/absolute/path/to/your/the/ble_smart_mask/folder" />

• Modify "Name" to your need

• In "macros":

  • Add the path to your nrf sdk you downloaded replace: C:/absolute/path/to/your/sdk
  • Add the path to "ble_smart_mask" folder in this repo. replace: C:/absolute/path/to/your/the/ble_smart_mask/folder
  • Use forward slashes "/" and absolute path (it' easier)

• Open segger embedded studio

• File -> open Solution -> navigate to "ble_mask.emProject"

• In project explorer, select the configuration you added (or go to Build -> Configurations.. and select your)

• Build -> Build ble_mask

• You can also delete the configurations you don't need

• Sleep mode
• different sample frequency per sensor
• Over the air firmware update
• Data link encryption (bluetooth bonding)
• Bluetooth reset