This is the RC-505 class, not a Ditto. Five stereo tracks, dedicated faders, Input FX vs Track FX, bounce-in, reverse, ½ / 2×, 1-shot, replace, undo. First pad sets the loop; the rest lock to it.
1–5 rec/play · shift+num stop · hold STOP to clear · space all · U undo · B bounce · Z–M play notes into the loop. Headphones. Sustain pedal = CC64 on the selected track.