Z02205

ZiLOG

Modem Controller

PS001000-MOD0599

17

DIAL MODIFIERS

Dial modifiers perform special functions within a dial com-

mand.

Example: ATDT9W1552368!@#71234;<CR>

The example instructs the modem to use tone dialing (T),

to access a number outside a PBX (9), to wait for dial tone

(W), to dial the number 1552368, to do a hook-flash (i.e.

timed break recall), to wait for quiet answer, and to issue

the PBX transfer code #7 before dialing extension number

1234, then to return to the Command state before initiating

the handshake.

Table 3. Dial Modifiers

Modifier

Function

0–9 A B C D # *

Dialing digits and characters. The digits and characters 0-9 A B C D # * specify what numbers the modem

dials. The characters A B C D # * work only when tone dialing is used. The characters are ignored when

pulse dialing is used. The characters A, B, C, and D may be disabled in countries prohibiting their use.

P

Pulse dialing. P selects the pulse method of dialing. P can be issued within a dial command or as a separate

command. The default method of dialing is Pulse.

R

Originates a Call in Answer Mode. R makes the modem handshake in answer mode so it can originate a call

to an originate-only modem.

T

Tone dialing. T selects the tone method of dialing. T can be issued within a dial command or as a separate

command. The default method of dialing is Pulse.

W

Waits for dial tone. W makes the modem wait for a dial tone before proceeding. If no dial tone is detected the

modem hangs up the telephone line and returns the NO DIALTONE result code.

,

Delays Processing of Next Character. A comma (,) makes the modem pause for the length of time in S-

register S8 before processing the next character in a dial string.

@

Waits for Quiet Answer. @ makes the modem listen for 5 seconds of silence before continuing. The modem

will wait up to the length of time in S-register S7. If 5 seconds (configurable by country) of silence are not

detected within the time period in S-register S7, the modem hangs up and returns the NO ANSWER result

code. If 5 seconds of silence are detected, the modem continues processing the other characters in the dial

string.

!

Timed Break Recall (Hookflash). A ! makes the modem hang up the telephone line for the length of time in

S-register S29, then take the telephone line off hook again. This is frequently used to access a PBX’s call

transfer function.

;

Returns to Command State after dialing. A semicolon (;) tells the modem to return to command state after

dialing without breaking the telephone line connection and without handshaking with the other modem. The

semicolon may only be used when calling a voice mail system that permits tones to transmit numbers when a

connection has been established.