The Arturia KeyStep is a versatile and portable musical tool that combines the functionality of a keyboard controller with a polyphonic step sequencer. It's designed to control both analog and digital devices, making it suitable for a wide range of music production setups. The KeyStep features a slimkey keybed with velocity and aftertouch sensitivity, offering a responsive playing experience. Its arpeggiator mode includes various patterns like up, down, inclusive, exclusive, random, note order, double up, and double down. The sequencer allows for 8 polyphonic step-sequences with Rest, Tie, and Legato note entry. Performance controls include REC, PLAY, and STOP buttons, as well as a Sustain HOLD button or sustain pedal jack. Chord play mode and SHIFT button selections for MIDI channel, GATE time, and SWING values add to its programmability. The device supports standalone operation via a DC jack and connects to computers via USB for MIDI control and use with Arturia's MCC editor. It also includes MIDI in/out ports and sync I/O ports that support various sync standards like 1 pulse per step, 2 PPQ (Korg Volca), 24 DIN sync, and 48 sync. CV/GATE outputs are also provided, with CV supporting 1Volt per octave and Volt>Hz modes, and Gate output adjustable for 5V or 12V gear. Capacitive-touch pitch bend and mod wheels offer expressive control. Each sequence can have up to 64 steps, and each step can accommodate up to 8 notes.