Alesis DATADISK Reference Manual page 55

SECTION 6
This means that when the sequence is sent, MIDI Clock, Song
Position Pointer (SPP), Start, Stop, and Continue messages are
filtered out (not sent), thereby preventing these messages from
interfering with the timing of the sequencer that the DataDisk is
syncing to.
Get user manuals: See SafeManuals.com
in the DataDisk starting at bar 2, beat 1, then that point
becomes the beginning of the sequence as far as
DataDisk is concerned. When the file is played back
from the DataDisk (synced to MIDI Clock), a Start
command will start playing from the beginning of the file,
which will be 1 bar ahead of the original sequence's start
location. Continue and Song Position Pointer commands
will be 1 bar ahead of the original sequence's location as
well.
c) Since a Continue command may occur anywhere within
a MIDI Sequence File, there may be a slight delay while
the DataDisk searches through the disk for the specified
location before executing the command. The DataDisk
will, however, remain in sync.
d) If, while syncing to an external sequencer, the DataDisk
is connected to the sequencer (such as an MMT-8) in a
MIDI loop (that is, sequencer MIDI output to DataDisk
MIDI input and DataDisk MIDI output to Sequencer MIDI
input as in figures 2A and 4 of the DataDisk user's
manual), then either the MIDI Clock must be filtered from
the DataDisk's output, or the sequencer should be set to
not receive MIDI Clock. This is done to make sure that
the speed of the sequence playback remains constant,
and is accomplished in the following manner:
1) Press the button four times. The display will then
MIDI
read:
MIDI CLOCK OUT
FILTER: OFF
2) Press the "up"
SCROLL
MIDI CLOCK OUT
FILTER: ON
button. The display will read:
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