Roland TR-626 Owner's Manual page 68

MIDI Function
88
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When the SYNC mode is set at TAPE SYNC or MIDI SYNC, and the Start
/Stop Key is pushed, the TR-626 will not begin to play until it receives
an external signal. To release it from this state do the following :
When in TAPE SYNC mode
The mode will change lo SYNC OFF by pushing the Start/Stop Key
again.
When
in
MIDI SYNC mode
The mode will change lo SYNC OFF by pushing the Start/Stop Key
again, then having the display indicate the SYNC mode setting, and
then pushing the Down Key.