Table of Contents
Advertisement
525
CE Test Switch
The CE test switch (switch
4
on the I
I
0
assembly) is a
diagnostic aid for the customer engineer to use in fault
isolation. There are two conditions in which the CE test
switch may be used that provide different results.
If the CE test switch is positioned on prior to display
station power-on, the diagnostics will loop continuously
until an error, other than a keyboard wrap test error, is
detected. Upon detecting an error, an error status line is
displayed at the bottom of the screen (520). An error
can be caused by pressing and holding any keyboard
key (key struck error).
If the CE test switch is positioned on after the display
station System Available indicator appears, the
2-second time-out is inhibited. With the 2-second
time-out inhibited, the diagnostics will not loop and the
information on the display screen will not be lost, even
if the System Available indicator disappears (meaning
that communication with the controller has been lost.)
3-32
CE Test Switch and Free Key Mode
530
Free Key Mode
The free key mode allows characters to be entered on
the keyboard and displayed on the CRT to test the
operation of the keyboard and character display circuits.
While in the free key mode, the display station
communicates with the controller, sending a code to the
controller and receiving back a character code for
displaying the character on the CRT.
The display station is in the free key mode after the
station has been powered on and, depending on the
system to which it is attached, ...
• Has the System Available indicator on, but no
sign-on menu displayed. or
• Is varied off, or
• Is in the online test mode, with the Prime Option
Menu displayed (see 610).
The following function keys may display an error code if
pressed while in the free key mode.
Print
Help
Roll+ (Up)
Roll+ (Down)
Duplicate
Enter
I
Record Advance
Attention
Command function keys
1 through 24
Field-
Use the online tests (600) to check these key
operations.
Advertisement
Table of Contents
