Specifications

7-32
Softkey Menu Descriptions
Input & Eye Menu
Input & Eye Menu
Path
or ,
Description
The key gives access to a menu of softkeys which enable the setting up
of the error detector Data Input and Clock Input electrical characteristics, including the
level at which the transition between a mark and a space is recognized (the 0/1 threshold
level). The active clock edge is the direction of clock transition relative to which the data
input is sampled.
The softkeys are as follows:
Toggles the selection of the zero-to-one threshold level between
manual and automatic.
Allows entry of the level at which the zero-to-one discrimination
will be performed, can be set in units of volts or millivolts.
To Select 0/1 Threshold Manual Mode
Select , set to then
press the softkey, (the key will be
displayed in inverse video). Use the RPG Display knob or the
Numeric Keypad to enter the desired 0/1 Threshold. The value
selected is displayed in the Error Detector Input and eye
control window on the display.
To Select Automatic Tracking
Select then set softkey to
, ( is underlined when selected). If for example
the pattern generator Data Amplitude were set to 500 mV and
the Data High Level to 0.0 V, the Automatic 0/1 Threshold
Mode value displayed will be approximately −250 mV.
Toggles the polarity of the input data pattern
Sets the time delay from the active clock edge to the time at
which the data is actually sampled. The value is entered in
picoseconds and may be negative, in which case the data is
sampled before the nominated clock edge. The entry is rounded
to the nearest picosecond.
input & eye MENU
input & eye
input & eye
input & eye
0/1 THR AUTOMAN
0/1 MAN THRSHLD
input & eye
0/1 THR AUTOMAN MAN
0/1 MAN THRSHLD
input & eye
0/1 THR AUTOMAN
AUTO AUTO
DAT POL NORMINV
DAT I/P DELAY