I've rebuilt Ben Williamson's "analog clock" #LEGO model which uses the #Mindstorms #RCX. Unfortunately, I do not have the fiber-optic component which he had used as rotation sensor. The rotation sensor I have still needs have its broken wire fixed. The clock gear defines a ratio so that the it needs to be driven with 48 discrete steps per hour (4 out of 5 minutes). Its programmed in #NQC. Mike Brandl has shared the PDF manual for this ancient technology on his website: https://lego.brandls.info/legbau.htm