C.7 - Preheat Red LED

The C.7 pin controls the power to a red LED which indicates that the sensors are in the preheat period, so as long as this LED is On, the sensors are not ready. This LED is not strictly necessary as all the sensors used have very short or no heating time, however if other sensors are used this LED will prove to be useful. Logic 0 switches the LED On.

Jenson Taylor 2008-01-25