Distributor: Description and Operation

The ignition timing is controlled by the MCU via the distributor. The distributor provides the MCU with engine speed information, expressed in voltage values, and this information is routed directly to the MCU. The MCU uses this information along with other sensor inputs to determine if the ignition timing should be advanced or retarded.

The distributor qualifies as both an input and an output device, because it sends voltage signals to the MCU and it also receives signals from the MCU to change ignition timing.