input line that is connected in series with at least one ignition coil the at least one ignition coil is driven during at least one current dwell period per an ignition cycle a signal representative of at least one spark is caused to be generated on the input line by the at least one ignition coil during the at least one current dwell period of the ignition cycle a controller is coupled to the input line the controller discriminates between single and multiple sparks over consecutive ignition cycles the signal is representative of at least one spark received on the input line from the at least one ignition coil the controller responsively forms an output waveform having substantially equally spaced pulses aligned with the first spark and the output waveform corresponds to the ignition cycle received on the input line application_number US 98516104 A description referring now to fig1 a and 1 b one example of a digital ignition system tachometer driver in accordance with the present invention is illustrated a vehicle electronic control unit ecu 260 is coupled to the primary winding of coils 264 and 265 via a splice 262 and lines 270 and 272 voltage is input at the 12v in terminal and at the 12v out terminal the.