Appendix 2: AT Command Set
Perle 833IS User Guide 243
Dn - Dial This command directs the modem to go on-line, dial according to the string entered
and attempt to establish a connection.
Dial Modifiers
The valid dial string parameters are described below. Punctuation characters may be
used for clarity, with parentheses, hyphen, and spaces being ignored.
0-9 DTMF digits 0 to 9.
A-D DTMF digits A, B, C, and D. Some countries may prohibit sending of these
digits during dialing.
T Select dialing: dial the numbers that follow until the next command is
encountered. Method of dialing (tone, pulse) will be based on the
configuration of the 833IS.
P Select dialing: dial the numbers that follow until the next command is
encountered. Method of dialing (tone, pulse) will be based on the
configuration of the 833IS.
R This command will be accepted, but not acted on.
, Dial pause: the modem will pause for a time specified by S8 before dialing
the digits following ",".
; Return to command state. Added to the end of a dial string, this causes the
modem to return to the command state after it processes the portion of the
dial string preceding the ";". This allows the user to issue additional AT
commands while remaining off-hook. The additional AT commands may
be placed in the original command line following the ";" and/or may be
entered on subsequent command lines. The modem will enter call progress
only after an additional dial command is issued without the ";" terminator.
Use "H" to abort the dial in progress, and go back on-hook.
( ) Ignored: may be used to format the dial string.
- Ignored: may be used to format the dial string.
<space> Ignored: may be used to format the dial string.
<i> Invalid character: will be ignored.
/ The ‘post dial’ character. The modem will wait for a phone call connect
before sending the characters following “/” using DTMF signaling.
* The 'star' digit. Valid only after the post dial character.
# The 'gate' digit. Valid only after the post dial character.
W Wait for dial tone: the modem will wait for dial tone before dialing the
digits following "W". If dial tone is not detected within the time specified,
the modem will abort the rest of the sequence, return on-hook, and generate