Arturia KeyStep 37 MIDI Keyboard Controller and Sequencer - Manual (Page 112)

9.10.3.11. Arm to Start
This determines the start/stop behavior of the sequencer when working with external clock
sources. Note that Arm to Start only applies when KeyStep 37 is synchronized to an external
clock source. This parameter does nothing when KeyStep 37's clock source is set to Internal.
OFF: This is the default setting and is common behaviour for sequencers receiving
synchronization signals from an external source (via MIDI or sync jack). In this mode, the
sequencer will automatically execute (run/pause/stop) when a synchronization signal is
received. That synchronization signal is then sent on to other devices that are daisy chained
downstream from KeyStep 37.
ON: When set to On, the sequencer no longer executes automatically but does pass on
synchronization signals to devices that are daisy chained to the KeyStep 37. In other words,
if sync is set to external and no synchronization signal is coming in, pressing the play button
will make the play button blink but the sequence will not play until a synchronization signal
comes in. This is a useful feature in cases where you want to have manual control over
KeyStep 37's sequencer but always want the synchronization signal to be passed through
to other devices connected downstream through the KeyStep 37.

!: If the sequencer is stopped and external clock signals are being received, pressing Play will start
the KeyStep 37 sequence at the position it would have been if it had been playing all along. For example,
if you have a 32 step sequence, KeyStep 37 is stopped and you press play on the clock master device,
the KeyStep 37 will pass the clock master's synchronization signal but not play the sequence until you
press Play. If you press the Play button between the 8th and 9th step of your sequence, KeyStep 37 will
begin playback of the sequence on its 9th step, in sync with the master clock.
9.10.3.12. Tie Mode
This determines how notes are "tied" together in the KeyStep 37 sequencer. "Tie to Previous"
(the default setting) ties the current note to the previous note in the sequence. The "tie to next"
option lets you tie the current note to the next note in the sequence. The Tie Mode setting is
stored with the sequencer preset, so loaded sequences will playback correctly.

!: Note that the behavior of KeyStep 37's Tap (Rest/Tie) button is different when "Tie To Next" is selected
in MCC:
9.10.3.13. Sequencer Length Update
This setting determines what happens to the "leftover" notes in a sequence that you shorten.
The default "Keep content beyond sequencer length" setting will keep any leftover notes so
that if you lengthen the sequence again, the notes continue to play as they did before the
shortening. The "Clear content beyond sequence length" setting clears leftover steps when
you shorten a sequence. In this case, if you lengthen the sequence back to its original length
the newly added steps will be silent (rests).
107 Arturia - User Manual KeyStep 37 - The MIDI Control Center