A low cost electronic ignition control system has been developed using a 4 - bit microcontroller. The microcontroller determines the crankshaft position from notches in a disc attached to the crankshaft and provides registration between engine rotation and proper cylinder firing. The controller outputs the proper signals to a special ignition coil and thereby eliminates the need for a conventional distributor.Timer peripherals are used to measure engine speed and to generate spark timing signals. Other spark timing determining variables are measured by an analog to digital converter. Problems relating to rapid engine acceleration are presented and solutions discussed.