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Programming Fundamentals
3-5
Special Keys
There are two keys on your 12-button or 16-button DTMF keyboard which have
special meanings to the controller. They are the star (*) and pound (#) keys.
(Technically, the # is called an
octothorpe , but we’ll just call it a Pound .). These
two characters are not allowed to be part of a password or macro name, and
they won't be found in root numbers or data digits.
Star (*) and Carrier Drop as Terminators
As mentioned earlier, the Star (*) digit serves as a terminator, indicating to the
controller that you have finished entering a command.
•
The (*) will always work as a terminator.
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The (*) method cannot be turned OFF, and will terminate any command.
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You can also allow a carrier drop to work as a terminator if you wish.
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The carrier drop method can be turned ON and OFF.
Why do we have the two methods?
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It's easier to terminate a command by simply releasing the PTT (push-to-
talk) button on your microphone, saving you one keystroke (the *). However,
there could be a carrier on the repeater's input frequency some day when
you enter a command. If the carrier continues to hold up the repeater after
you've released the PTT button, your command won't be executed. Entering
the (*) at the end of the command will guarantee that the command is
properly terminated.
•
A second reason for using the (*) terminator is that you may enter a series
of commands, one after the other, without releasing the PTT button. (You
do not have to wait for the acknowledgment message before entering the
next command.) You must, of course, use the (*) terminator when entering
commands from a Touch-Tone™ telephone, since there is no carrier drop
for the controller to detect.
Pound (#) as Clear or Abort Key
The pound (#) digit serves as the Clear or Abort key. It indicates to the
controller that you have made an error, and you wish to clear the command
buffer. (The command buffer is a holding area of the partially-entered
command.)
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The (#) key only works if a command is still in the buffer, and has not been
executed.
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When you enter the terminator, the command is immediately executed and
it is too late to clear the buffer.
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You may start entering the next command immediately after pressing the
(#) key.