The Replay1 Daughterboard has a MIDI Interface to both transmit and receive MIDI data.
A MIDI interface or Breakout Board option can be purchased from hobbytronics. On the Replay1, this is connected via 4 pin headers at the front of the Daughterboard.
The MIDI Breakout Board gives you access to the MIDI communication protocol, so you can control synthesizers, sequencers, and other musical devices. See this link for more information.
Note: Replay1 Daughterboard MIDI connections:
At this time, only the P2 Comms1 port is working, further work is required for P3 Comms2.
Popular Keyboards/Synths that were used at the time include the popular AKAI X7000. Others also included the D-10 (Multi Timbral Linear Synthesizer) from the Roland Company.
Below an example of a MIDI Sequencing program called, Dr.T’S Music Software (KCS).
It was popular on both the Amiga and AtariST Computers as well as Macintosh.