Multichannel Systems STG3008-FA Manual - Manual (Page 62)

STG3008-FA Manual
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Use Trigger as Gate
Channels associated with a Trigger input will be active as long as the condition of that trigger is
1 (HIGH) and switched off as soon as the condition becomes 0 (LOW). If the stimulation protocol
is shorter than the gate, it will stop at the predefined time, regardless of the gating trigger. If
the stimulation protocol is longer than the gating trigger, stimulation will stop when the gating
trigger ends. For example, if you want to produce a repeated rectangular pulses that last as long
as the gating trigger is HIGH, you can do the following: program a single rectangular pulse and
activate the continuous mode. The pulses will start as soon as the gating trigger becomes HIGH,
and stop as soon as the gating trigger becomes LOW. If the voltage of the stimulation channel is
different from 0 at the time the gating trigger ends, the channel will be switched off immediately.
If you stop the stimulating protocol manually during the gating trigger in HIGH, stimulation is
stopped but immediately restarted, and goes on until the gating trigger ends.
Warning: Once selected, this setting will become the default setting for all opened files,
until unselected. So if you observe unexpected behaviour when triggering the STG, check
the Trigger settings.
Sweep Count
The number of sweeps are counted and displayed for each of the four triggers at the bottom
of the main window.
Please note that not the number of stimuli but the number of sweeps is counted, whereby one
sweep is defined as one complete run of the programmed stimulation pattern, as displayed in the
main window. So, if five stimuli are programmed, and the repeat rate in the Trigger Setting menu
is set to six, 30 stimuli will be delivered but the sweep count will be six.
Sweeps are not counted online, the final number is displayed after the STG has been stopped.
The number of sweeps per channel is not put to zero automatically every time the stimulation
is started. Instead, a reset only happens if a trigger is again used in the new stimulation. So,
if a stimulation file uses trigger one and two with a repeat of three each, the display will show
1:3 2:3 3:0 4:0 at the end of the stimulation. If afterwards for example a stimulation file
is started which uses only trigger four in continuous mode, and this file is stopped after 15
repeats of the programmed stimulation pattern, the display will show 1:3 2:3 3:0 4:15.