Gpi i/o – Grass Valley 8972PX User Manual
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8972PX — Instruction Manual
Installation
GPI I/O Control Interface
The GPI I/O connector inputs provide a means to enable (Force) the Pri-
mary, Secondary, or Alternate input signal to become the Program Output.
The inputs are suitable for a connection to a relay contact (switch button) or
to an open collector output in a typical circuit.
When the GPI Exclusive Control is activated, the Program Output can only
be changed using one of the Switch to Primary, Switch to Secondary, or
Switch to Alternate GPI controls until all GPI controls are de-activated.
To activate a GPI In function, a switch closure must be provided between
the GPI In common ground (pin 13) and the GPI In function for a minimum
of 80ms. To change states (deactivate the selected input) the contact closure
must be open for at least an 80ms duration.
for a complete list of the GPI I/O function pin
numbers. An example of a GPI interface using relay contacts is shown in
. A typical Open Collector example is shown in
Note
Use either Open Collector or relay (switch button) controls but not both
methods in the same GPI interface configuration.