Multi-Tech Systems MT3334SMI manual AT+FRH=3 No Carrier

Chapter 3 - Class 1 Fax Commands

Table 3-3. Single-Page Class 1 Answer & Receive Example

		Action by	Action by
Command	Respone	Local Modem	Remote PC
AT+FCLASS=1	OK	Set Class to 1
	RING	Detect Ringing	Dial, send CNG
ATA		Off hook,
		Send CED,	Get CED
		Send V.21 carrier	Detect carrier
	CONNECT	Send flags	Detect flags
<CSIframe data>		Send CSI data	Receive FCS
<DLE><ETX>		Send FCS
	CONNECT	Send flags
<DISframe data>		Send DIS data	Receive DIS
<DLE><ETX>		Send FCS and flags
	OK	Drop carrier
AT+FRH=3		Detect carrier	Sends V.21 carrier
	CONNECT	Detect flags	Send flags
	<TSI frame data>	Receive TSI	Send TSI frame
	<DLE><ETX>	Receive FCS	Send FCS
	OK	Accept FCS
AT+FRH=3	CONNECT
	<DCS packet data>	Receive DCS	Send DCS frame
	<DLER><ETX>	Receive FCS	Send FCS
	OK	Accept FCS
AT+FRH=3	NO CARRIER	Detect loss of	Drop carrier
		carrier
AT+FRM=96			Wait 75 msec.
	CONNECT	Detect carrier	Send V.29 carrier
	<TCF data>	Receive TCF	Send TCF data
	<DLE><ETX>	Detect carrier loss	Drop carrier
	NO CARRIER
AT+FTH=3		Send V.21 carrier	Detects carrier
	CONNECT	Send flags	Detects flags
<CFRframe data>		Send CFR frame	Receives CFR
<DLE><ETX>		Send FCS
	OK	Drop carrier
AT+FRM=96
	CONNECT	Detect carrier	Send V.29 carrier
	<page image data>	Receive page	Send page data
	<DLE><ETX>	Detect carrier loss	Drop carrier
AT+FRH=3			Wait 75 msec.
		Detects carrier	Sends V.21 carrier
	CONNECT	Detects flag	Sends flag
	<EOP frame data>	Receives EOP	Sends EOP packet
	<DLE><ETX>	Receives FCS	Send CRC
	OK	Accepts FTS
AT+FRH=3	NO CARRIER	Detects loss of	Drops carrier
		carrier
AT+FTH=3		Send V.21 carrier	Detect carrier
	CONNECT	Send flags	Detect flags
<MCF frame data>		Send MCF frame	Receive MCF frame
<DLE><ETX>		Send FCS
	OK	Drop carrier
AT+FRH=3		Receives carrier	Send V.21 carrier
	CONNECT	Detects flags	Send flags
	<DCN frame data>	Receives DCN	Send DCN frame
	<DLE><ETX>	Receives FCS	Send FCS
	OK	Accepts FCS
AT+FRH=3	NO CARRIER	Detect loss of	Drops carrier
		carrier
ATH0	OK	Hangs up

MT3334SMI 39