The Design Process for the Brake Temp Sensor was split into the following parts:
1. Breadboarding the sensor, screen, and SD card
2. Software
3. Protective Circuitry
This breakdown allows me to work from simplest task to hardest, and ensure there is proper functionality before moving to the next stage.
1. Breadboarding
Above were my stages of breadboarding. The first design (left) consists of only the K-type thermocouple and the LED screen connected to an Arduino Nano. I used an Arduino library supplied test code whilst running a generic splash screen to ensure both sensor and screen functionality. Sensor temps were printed in the Arduino IDE console.
On the right, the Arduino Nano was replaced with an Arduino Mega. The Nano lacked the memory to run all three components and necessitated the change. The same process outlined above was applied to the circuit on the right. Essentially, all three were tested simultaneously to establish compatibility in terms of current draw and memory usage.