MULTICHANNEL SYSTEMS USB-ME128-System, System Manual

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USB-ME-System Manual
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5.9 Triggering / Digital Input does not Work
You have connected a TTL source (for example, the Sync Out of a stimulus generator) to the digital output
D0 of the
USB-ME-System , and configured the virtual rack in MC_Rack for triggering displays or data
acquisition by the TTL source, but you do not see any sweeps.
Possible causes:
? The TTL source does not generate true TTL signals (5 V TTL level), or the TTL pulse duration
is too short in combination with the sampling rate, so that the pulse is missed in-between two data points.
The USB-ME-System can only accept TTL signals (5 V TTL level) as a digital input stream. The TTL pulse
needs to be optimized according to the sampling rate. Otherwise, a detection of the trigger cannot be
guaranteed.
? The software settings for the Trigger Detector do not match with the hardware configuration.
In MC_Rack, add a Trigger Detector to your virtual rack, and select the Digital Data D1 input stream as the
Trigger. Check the pin layout of the digital IN / OUT connector and make sure that the same bit input that
is connected is selected in the software. (The standard settings of the Trigger Detector are for using bit 0.)
Mask all unused bits. Select the appropriate logical state (generally HIGH) for triggering. Please see the
MC_Rack help or manual for more details.