Arturia KeyStep Pro Keyboard with Advanced Sequencer and Arpeggiator - Manual (Page 76)

Here are a few more handy things to know about this feature:
• For all the Chord mode functions described above, you can use a sustain pedal
instead of the HOLD button. (The pedal will not flash, of course — but that would
be cool.)
• To enter or exit Chord mode, hold down the 'Shift' button and then tap the Tie/
Rest/Chord button.

CAUTION: Neither the memorized chord nor your arpeggio are saved when the KeyStep Pro is
powered down.
70 Arturia - User Manual Keystep Pro - Making Tracks