Faximum TechNote #119

(http://www.faximum.com/technotes/119)

TITLE:    #119 - Modem does not answer incoming call

KEYWORDS: receive modem ring answer incoming call

RELEASE:  All

CLASSIFICATION: All

PROBLEM:  Faxes are not being received.  The trace shows nothing after
	  the "AT+FCR=1" command sent to the modem and the "OK"
	  response from the modem.

	  In a normal situation the trace would show the modem generating
	  "RING" messages when an incoming call has been detected (this
	  assumes that the modem init string contains "S0=0", which is
	  default for all Faximum installation except when operating in
	  data/fax sharing mode).


CAUSE:	  The modem is not informing the fax software that ring signals
	  are being received.  When the Faximum software is configured
	  for dedicated operation (i.e. not configured for data/fax
	  sharing on those systems that support it), the software waits
	  for a RING message from the modem indicating that a call is
	  coming in.  At this point faxlisten spawns the faxcico daemon
	  to actually receive the call and the faxcico daemon issues the
	  ATA command which causes the modem to answer the phone.


SOLUTION: There are a couple of possible causes of this problem.

	  1.  Check that the phone line to the modem is connected to the
	      "Line" jack in the back of the modem and not the "Phone"
	      jack.  Some modems will send faxes with the phone cable
	      plugged into the wrong jack but will not receive faxes.

	  2.  Run faxlisten in trace mode (for Faximum ELS/PLUS customers,
	      see Chapter 4 of your Installation Guide and Release Notes;
	      for Faximum Client/Server customers, see TechNote #112).
	
	  3.  Place a call to the fax modem (for the purposes of this test
	      the call need not come from a fax machine; just dial the
	      fax modem from another phone).
	
	  4.  Check the fax modem to see if it is detecting the incoming
	      call:
		a) listen to the fax modem (most modems will make a sound
		   when they detect an incoming call);
		b) look at the modem lights (most modems will flash a light
		   on their front panel to indicate an incoming call); and
		c) look at the trace to see if the modem is generating any
		   "RING" messages.

	  If you see evidence of the incoming call (lights flashing and/or
	  modem making sounds) but do not see any "RING" messages, then your
	  modem is probably defective and you ought to contact the
	  Technical Support Department at the modem manufacturer.

	  If there is no visible evidence of the incoming call you ought
	  to check the phone cable and phone line to make sure that
	  incoming calls can be received properly.  Try plugging a phone
	  into the "Phone" jack at the back of the modem and repeating
	  the above steps.  If the phone rings but the modem shows no
	  sign of detecting the phone call, then your modem is probably
	  defective.  If the phone does not ring then your phone line is
	  probably defective.



	  Should you have any questions about analysing the output of a 
	  Faximum trace, please fax or e-mail the entire trace to 
	  Faximum Technical Support.

	  E-mail:	support@Faximum.com
	  Fax:		1 (604) 926-8182

Last Updated: Wed Aug  2 09:03:09 PDT 1995
Tech Note:    119
Copyright 1995 Faximum Software Inc., All Rights Reserved.
The complete set of Faximum TechNotes are available on the Internet at 
	http://www.faximum.com/TechSupport
© Copyright 2001 Faximum Software Inc. All Rights Reserved.