MC55_ATC_V04.00 Page 138 of 475 3/17/06
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7.11 ATS0 Set number of rings before automatically answering a call
Syntax
Parameter Description
000(&F) Automatic answer mode is disabled.
001-255 Enable automatic answering after specified number of rings.
Notes
This command works for MT data and fax calls.
Autoanswering of CSD data and fax calls is supported on ASC0/Mux1 only.
A CSD call will not be automatically answered when the module is in GPRS online mode, but it is possible in
GPRS command mode. The application can detect a call by evaluating the RING line and determine whether
to change into GPRS command mode or stay in GPRS online mode until GPRS is available again. To answer,
to reject or to wait for automatically answering the incoming call the application has to switch into GPRS com-
mand mode.
If <n> is set to higher values, the calling party may hang up before the call is automatically answered.
The correlation between ATS7 and ATS0 is important.
Example: Call setup may fail if ATS7=30 and ATS0=20.
Setting is local to the interface. It is allowed to have different settings on different interfaces. In such cases
the interface 'wins', which is idle and uses the smallest <n> value.
The ATS0 write command is PIN protected.
According to "3GPP TS 27.007 (GSM 07.07): AT command set for User Equipment (UE)", ATS0 is also used
as GPRS compatibility command to answer automatically to a network request for PDP context activation
(see Section 11.19). Therefore, when the ATS0 write command is issued with <n> greater than 0, the ME will
attempt to perform a GPRS attach if not yet attached and if configured to do so (due to the setting
AT^SCFG="GPRS/ATS0/withAttach","on").
If the automatic GPRS attach fails the ME keeps trying to attach for approx. 5 minutes, before ATS0 ends up
with "ERROR" or "+CME ERROR: unknown", though the new <n> value takes effect. To avoid the risk of long
response times to ATS0 in such case take care that the parameter AT^SCFG=<gs0aa> is off, if autoanswer
mode is not needed for GPRS or if the mobile works in non-GPRS networks.
The GPRS attach will not be performed on recalling a stored user profile with ATZ or on powerup, even though
a value <n> greater than 0 was stored in the user profile with AT&W.
Read Command
ATS0?
Response(s)
<n>
OK
ERROR
Write Command
ATS0=<n>
Response(s)
OK
ERROR
Reference(s) PIN ASC0 ASC1 MUX1 MUX2 MUX3 Charge Last
V.250 § % % % % % ! ! !
<n>(num)(&W)(&V)