"The Nixie Wristwatch does not have a microprocessor, or programmed components. Standardized low-power CMOS logic drive the nixies in DC mode. A number of different circuits were considered when designing the watch. I eventually settled on the simplified logic approach, similar to the circuits used when LED digital wristwatches were entering the consumer market around 1970. Of course, I couldn't place the circuitry on one IC chip as they had done."