Specifications

HYLAFAX-CONFIG(5F) HYLAFAX-CONFIG(5F)
empirically some machines may need more time.
Class1ModemHasDLEBug
Used to indicate that the modem does not correctly duplicate DLE characters in the V.21 commu-
nication to the DTE.
Class1MsgRecvHackCmd
If receive failures occur due to +FCERROR just prior to image data reception, setting
Class1MsgRecvHackCmd to AT+FRS=1 may help.
Class1RecvAbortOK
The time, in milliseconds, to wait for an ‘‘OK’’ result code from the modem after aborting an
HDLC frame receive (‘‘AT+FRH=3’’). If this number is zero, then the modem is assumed to not
correctly implement aborting and instead the driverwill wait 200ms, flush anyinput, and then
send ‘‘AT\n’’ and wait 100ms for an ‘‘OK’’ result.
Class1RecvIdentTimer
The time, in milliseconds, to wait for an initial DCS when receiving a facsimile. CCITT recom-
mendation T.30 specifies this as the value of the T1 timer.Howev e r, adaptive answering schemes
such as that described above under the AdaptiveAnswer parameter may require that this timer be
shortened.
Class1RMPersistence
The number of times that an attempt to receive the high-speed data carrier should be made, result-
ing in +FCERROR, before the low-speed message carrier reception is attempted. Some modems
are quick to (perhaps incorrectly) return +FCERROR, and for those modems a value of 2 or 3
should be used. Formodems that are not quick to return +FCERROR, a value of 1 should be used.
Proper tuning of this can provide a type of "adaptive reception control" for modems that accurately
return +FCERROR without supporting Class1AdaptRecvCmd. Forthose modems that support
Class1AdaptRecvCmd, Class1RMPersistence should probably not be set at 1, although +FCER-
RORshould almost neveroccur with such modems.
If the modem does not support the reporting of +FCERROR or adaptive reception control, then
Class1RMPersistence should probably be set at 0, which causes the timeout looking for the high-
speed data carrier to be shortened, thus increasing the likelihood of recovery from anydissynchro-
nization. When Class1RMPersistence is other than 0 it is assumed that the +FCERROR reporting
or Class1AdaptRecvCmd is functional and therefore the timeout looking for the high-speed data
carrier is lengthened.
Class1SwitchingCmd
The command used to ensure that the sending facsimile device has turned offits modulator (i.e.
loss-of-carrier) as recommended by T.31: Appendix II.1.
Class1SFLOCmd
The command to setup software (XON/XOFF)flow control between DTE and DCE when operating
in Class 1. This command is issued immediately after sending the Class1Cmd to switch the
modem to Class 1 operation.
Class1TCFMaxNonZero
The maximum percentage of non-zero data bytes permitted in an acceptable received TCF. Note
that this number does not include anyleading non-zero data in the receiveddata. See also
Class1TCFMinRun.
Class1TCFMinRun
The duration, in milliseconds, of the minimum run of zero data in an acceptable received TCF.
This value should be specified according to a 1.5 second transmission of zero data (i.e. it should be
between 0 and 1500). See also Class1TCFMaxNonZero and Class1TCFMinRunECMMod.
Class1TCFMinRunECMMod
The factor by which Class1TCFMinRun should be modified in the case of an ECM session. As
ECM protocol allows retransmissions it is commonly faster to accept a lesser-quality data stream
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