Comtech EF Data CDM-425, Installation And Operation Manual

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CDM-425 Advanced Satellite Modem
Revision 0
Front Panel Operation 6–4 MN-CDM-425
6.1.2 Keypad
The keypad has an auto-repeat feature. When you hold
down a key for more than one second, the key action
repeats, automatically, at the rate of 15 keystrokes per
second. This is particularly useful when editing numeric
field with many digits, such as frequency or data rate.
The keypad functions as follows:
Key Description
ENTER
Use this key to display the nested menu for a selected function, or to execute (save) a
configuration change.
CLEAR
Use this key to back out of a selection or to cancel a configuration change that has not been
executed using ENTER. Press CLEAR to return to the previous menu screen.
◄ ►
(Left, Right)
Use these keys to navigate between available selections, or to move the cursor position, on any
menu screen.
▲▼
(Up, Down)
Use these keys primarily to change the alphanumeric selection (i.e., numbers for configuration
data, letters for text strings) at the current cursor position, or to scroll through pre-defined
parameter settings that may be provided at the current cursor position.
6.1.3 Vacuum Fluorescent Display (VFD)
The CDM-425 features a Vacuum Fluorescent
Display (VFD). The VFD is an active display
showing two lines of 40 characters each. It
produces a blue light with adjustable brightness.
Compared to a Liquid Crystal Display (LCD), the VCD provides superior viewing characteristics
and does not suffer problems of viewing angle or contrast.
On most menu screens, you will observe a flashing solid block cursor, which blinks at a once-per-
second rate. This indicates the currently selected menu item, digit, or field. Where this solid block
cursor would obscure the item being edited (e.g., a numeric field) the cursor automatically
changes to an underline cursor.
6.1.3.1 Screen Saver
If the operating unit is left displaying the same
screen for weeks at a time, the VFD could
become burnt with this image. To prevent such
burn-in, a screen saver feature activates after
one hour. The screen saver messages loop from right to left across the screen. The top line of the
display shows the user-editable Circuit ID; the bottom line shows the current status of the modem
followed by the message ‘Press
any key… ’ as shown here. Press any key to restore the previous
screen .