si2493 Silicon Laboratories, si2493 Datasheet - Page 23

• Manufacturer Part Number: si2493
• Description: V.92 Isomodem With Global Daa
• Manufacturer: Silicon Laboratories

Command
Dn
Hn
H0
En
E0
E1
A/
A
$
Table 8. Basic AT Command Set (Command Defaults in Bold)
Display AT command mode settings.
Answer incoming call
Re-execute last command. This is the only command not preceded by “AT” or followed by a
<CR>.
Dial
The dial command, followed by 1 or more dial command modifiers, manually dials a phone
number:
Local DTE echo
Disable
Enable
Hook switch.
Go on-hook (hang up modem).
Modifier
! or &
, or <
@
W
G
P
L
T
;
Rev. 1.3
Function
Flash hook switch for FHT (U4F) ms (default: 500 ms)
Pause before continuing for S8 seconds (default:
2 seconds)
Return to AT command mode
Wait for silence.
Polarity reversal detect. By placing the “G” character in
the dial string (i.e. ATDTG1), the Si2493 will monitor the
telephone line for polarity reversals. If a busy tone is
detected, the Si2493 will report “POLARITY REVER-
SAL” if a polarity reversal was detected or “NO POLAR-
ITY REVERSAL” if a polarity reversal was not detected.
In each case, the result code is followed by “OK”. If the
S7 timeout occurs before a busy tone is detected, the
Si2493 will report “NO CARRIER”. Polarity reversal
monitoring begins after the last digit is dialed and ends
when the busy tone is detected or S7 timeout occurs.
Note: It is not possible to establish a modem connection
Redial last number.
Pulse (rotary) dialing—pulse digits: 0, 1, 2, 3, 4, 5, 6, 7,
8, 9
Tone (DTMF) dialing—DTMF digits: *, #, A, B, C, D, 0,
1, 2, 3, 4, 5, 6, 7, 8, 9.
Wait for dial tone before continuing for S14 seconds
(default: 12 seconds). Blind dialing modes X0, X1 and
X3 do not affect the W command.
If the DOP bit (U7A, bit 7) is set, the “ATDTW” com-
mand will cause the ISOmodem® to pause dialing and
either report an “OK” if a dialtone is detected or “NO
DIALTONE” if a dial tone is not detected.
Action
when using this command.
Si2493
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