• Transfer Line Data to Scratchpad. If the scratchpad is empty, pushing a
line select key transfers the respective line data to the scratchpad.
• Transfer Scratchpad Data to Line Fields. Once data has been entered
into the scratchpad either through line selection or manual keyboard
entry, it can be transferred to any of the allowable line select fields on a
page. To transfer the data, push the key adjacent to the line where the
scratchpad data is intended.
SCRATCHPAD
Alphanumeric entries are made to the scratchpad using the keyboard. As
each key is pushed, the character is displayed in the scratchpad. Information
in the scratchpad does not affect the FMS until it is moved to another line on
the display.
Data is retained in the scratchpad throughout all mode and page changes.
Scratchpad is also used to display FMS messages which can be of two
types: Alerting or Advisory.
Alerting messages also trigger the amber MSG annunciator on the LH side
of the HSI.
Any entry already in the scratchpad is placed in a stack. The CLR key clears
a message and displays the next message or entry from the stack.
Correcting whatever caused the message clears some of the messages.
ALPHANUMERIC KEYBOARD
The alphanumeric keys are used by the pilot to input data into the FMS
scratchpad.
The Alphanumeric keyboard includes:
• letters of the alphabet
• the numbers 0-9
• the decimal point
• the plus/minus
• the space character (SP key)
• the slash
CLR KEY
This key performs the following functions:
• When a message is displayed in the scratchpad, pushing the CLR key
deletes the message.
• When a scratchpad entry begins with an asterisk (*) or pound sign (#),
pushing the CLR key removes the entire entry.
• When an alphanumeric entry is made in the scratchpad, one character
is cleared from the scratchpad (from right to left) each time the CLR
key is pushed. If the CLR key is held down after the first character is
cleared, other characters are cleared, one at a time, until the key is
released.
DEL Key.
The DEL key is used to delete items from the FMS. When the DEL key is
pushed, *DELETE* is displayed in the scratchpad. The DEL key can be line
selected to delete waypoints or other items displayed in the MCDU data
fields.
The DEL key is also used to return default values after entries have been
made.
The DEL key can also be used in the scratchpad edit mode. With a dash (-)
at the end of the scratchpad entry, pushing the DEL key deletes the entire
scratchpad entry.
BRIGHTNESS CONTROL
Both manual and automatic (photo sensor) brightness controls are used to
increase or decrease the MCDU display brightness.
When manually selected, a bright/dim bar is displayed in the scratchpad.
The bright/dim bar level is controlled by pushing BRT or DIM.
Following manual adjustment, the photo sensors monitor the ambient light
and maintain the brightness level of the MCDU display over various lighting
conditions.
Note that the brightness can be adjusted during evening hours such that,
during daylight hours, the display cannot be seen.