How Digium phone digitmap works
The dial plan or digit includes settings that specify the behavior of the phone as a user enters a number in off-hook dialing mode. The digit map is the setting that describes different patterns of numbers. When a number matches a pattern, the number is sent to Asterisk to place the call. The pattern may include a timer at the end. If no numbers are entered before the time expires, the number matching the pattern will be sent. If additional numbers are entered before the time elapses, the pattern no longer matches.
Digit Map Syntax
digitmaplist := digitmap ( '|' digitmap )*
digitmap := digitstring | digitstring timer
digitstring := atom+
atom := literal | class | wildcard
literal := digit | '*' | '#'
digit := '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'
class := '[' range+ ']'
wildcard := '.'
range := digit | digit '-' digit
timer := T digit*
A digit map with a timer, but no specified time value, defaults to 4 seconds
Example
[0-9]xxxT | 911 | 9911 | 411 | 611 | 011xxxx.T3 | 1xxxxxxxxxx | [2-9]xxxxxx | *xx.T3
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