Aim AXC-FDX-2, Руководство по оборудованию

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3 . Structure of the AXC-FDX-2
AXC-FDX-2 Hardware Manual 14
3.3 External Trigger Inputs and Outputs
For external triggering, separate trigger input and trigger output lines are provided. Each
Trigger I/O can be mapped via software to a MAC or a dedicated functionality within the
MAC. Inputs can be used for example to start or stop the receiver, or to start the sender.
Outputs can be mapped for example to complex Filter and Trigger function blocks within
the PL / BIU Firmware and signal user definable events.
The minimum input trigger pulse length must be greater than 75 nanoseconds to be
detected. The trigger inputs are high active and their voltage level is of type TTL and is
+5.0V tolerant. Varistors on the Front IO are placed nearby connector to suppress
peaks of glitches (ESD sparks).
3.4 User programmable Discrete I/O
The AXC-FDX-2 module provides four user definable discrete I/O signals. Discrete input
signals are always active whereas the discrete output signals are per default inactive.
An open collector circuitry is used for the discrete output with approximately 4V
provided by default. An external voltage from 0 to 35V can be supplied externally for
switching higher voltages.
Please Note:
The discrete outputs don’t provide a series resistor for over current protection. In case a
discrete input is used, make sure that the output-mode for that discrete is disabled,
before connecting an external voltage, otherwise a high short circuit current to GND can
damage the output transistor.