Future Retro Swynx - Manual (Page 7)

MIDI IN
The MIDI IN accepts MIDI clock and note information.
When using the Swynx for clock synchronization, connect the MIDI OUT
of the MIDI device acting as your master clock to the MIDI IN of the
Swynx.
When using the Swynx as a CR-78 programmer, connect the MIDI OUT
of a MIDI keyboard to the MIDI IN of the Swynx.
MIDI OUT
The MIDI OUT sends MIDI clock for syncing external MIDI sequencers
and drum machines.
Connect this MIDI OUT to the MIDI IN of the external device you want to
sync.