Chapter 8 - Special Functions
8-9
The timing relationship between the Caller ID (if enabled), EDR, and ring
detection is as follows:
ring1 ring2 ring3
***--------***--------***------------------------------
3sec 3s 3s 3s S7 timeout
+------+---+------+---+------+---+-------------+----
CID/EDR RD EDR RD EDR RD EDR RD
CID=Caller ID task RD=Ring Detection task EDR=EDR task
Note: During the EDR period, any AT command will disable the EDR
function.
EDR Application Example
If we use ZFAX as our fax receiving application and we don’t want it to answer
the call unless it is a fax call, the way to set it up would be:
1. Set ZFAX to answer on 2 rings.
2. Set S51.0=1 to enable EDR and report RING twice. The modem will not
report a normal RING and ZFAX will not answer a call unless EDR RING
is reported.
3. Set
S51.4=1 to enable fax CNG tone detection. It is reported as RING.
4. Set
S51.2=1 to enable DTMF tone detection. It is reported as RING. If the
remote fax machine does not generate the CNG tone, ask a fax caller through
your answering machine message to press “*” (or any other DTMF key) if he
or she wants to send a fax.
Save the settings in a profile and reset the modem with AT&WZ.