din sync was introduced in the early 1980s by roland corporation for the synchronization of music sequencers, drum machines, arpeggiators and similar devices. it has since been superseded by midi, in the mid to late 1980s. the din sync standard consists of two signals, clock (tempo) and run/stop. both signals are ttl compatible, meaning the low state is 0 v and the high state is about +5 v.