FYI, Suzuki's term for the black box is simply the "Ignitor Unit." Here's their description of the Ignition System (Digital Ignitor):
"The fully transistorized ignition system consists of a signal generator, ignitor unit (including 8-BIT MICROCOMPUTER and CERAMIC 4MHZ VIBRATOR), ignition coils and spark plugs. The characteristic of the ingnition timing is programmed and stored in the "ROM" (READ ONLY MEMORY) of the ignitor unit. The signal genarator comprises the rotor tips and pickup coil.
The signal generator is mounted at the starter clutch. The induced signal in the signal generator is sent to wave-form arrangement circuit, and CPU receives this signal and calculates the best ignition timing from the signal of ceramic vibfrator and data stored in the ROM. The CPU outputs signal to the transistor of the I.G. coil output circuit which is connected to the primary windings of the ignition coil which is turned OFF and ON accordingly, thus it induces the secondary current on the ignition coil secondary windings and produce the spark between spark plug gaps.
Ignition cut-off circuit is incorporated in the ignitor unit to prevent over-running engine. If engine r/min. reaches 13,500 r/min., this ciruit cuts off the ignition primary current for all spark plugs."
And there you have it.
