Software
Software Architecture
We use FreeRTOS, a lightweight realtime operating system to schedule tasks for the microcontroller to handle. TRAC uses three threads:
Temperature Control
Main Control
Display Control
Separating systems into different threads allows us to sleep the threads we are not using to save valuable clock cycles. For example, we can sleep the temperature control thread when we are on the start screen.
User Interface
TRAC's UI was designed with high-stress scenarios in mind. There are only four screens with simple layouts to minimize the risk of confusion and user error.
The screens are:
Home Screen - Shows the logo and a start button to begin testing
Test Setup Screen - Displays both the target and current temperature, as the temperature control cycle runs. Once up to temperature, the user is prompted to insert the blood chip.
Testing Screen - Tells the user that the test is currently running.
Results Screen - Displays the estimated blood coagulation levels.
See it in action here: