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1257 User Manual
Using the Front Panel Controls 3-10
EADS North America Defense
Test and Services, Inc.
©
2001
(18 characters). If pathnames are defined greater than 18
characters, only the first 18 characters will be visible. It is also
only possible to selectively filter the first 18 characters using the
display filter masks. Characters extending beyond this limit are
treated with wildcards when the filter mask is applied.
Closing a Path
The 1257 front-panel enables the user to manually close and open
pathnames.
For example, suppose four pathnames have been defined using
the remote interface for a combination of different relays and plug-
in cards – “PATH1”, “PATH2”, “PATH3”, and “PATH4”:
1. Press the top key next to the display. This selects the top
display line so that you can change it. The selection markers
“>” and “<” appear on the line to indicate that it is selected.
Rotate the knob until the top line reads:
>---PATH CONTROL---<
2.
Select line 3 (next to the top line) by pressing the third key.
This allows the pathname to be selected from a list of those
that are presently defined in the 1257 switching system:
---PATH CONTROL---
Select Filter Mask
>PATH1_____________<
Status: Open
3. Rotate the knob until line 3 indicates the desired pathname
(“PATH2” for this example):
---PATH CONTROL---
Select Filter Mask
>PATH2_____________<
Status: Open
4. Press the fourth key to select line 4. Rotate the knob until
the display reads:
---PATH CONTROL---
Select Filter Mask
PATH2_____________
<Set to?: Closed
5. Press the fourth key to confirm the closure of the desired
pathname. The entire path then closes, and the display
indicates the updated status on line 4:
---PATH CONTROL---
Select Filter Mask
PATH2_____________
> Status: Closed <