2 MIDI IN mergées with messages transmitted by the device;
1 MIDI OUT
Virtually any MIDI message can be assigned to different elements, including Start, Stop, Continue, and even tempo. Some limitations, however: we must define a global midi channel, not sending SysEx or RPN / NRPN, no tap tempo, a single program memory ... But it dates from the mid-80s, it's excusable, but prevents me from giving the note to the Swiss Army knife Max du Midi, paired with a Yamaha MEP4 ( https://fr.audiofanzine.com/controleur-midi-divers/yamaha/MEP-4/ ) !
I just realized, typing this review, it could make a pretty cool control surface for Cubase ... For cons, the object is very rare, I had to put 3 or 4 years to find mine, and of course it is NOT for sale! :-P