[comp.os.msdos.programmer] FAX id technique

Rob.Wedlock@samba.acs.unc.edu (Rob Wedlock) (01/06/91)

Hi... I was wondering if there is a protocol for FAX transmissions, i.e.
i?s there anykind of inquiry I can send to it to recive back it's model
or parameters? Or is it more of a dumb terminal???

oeschi@netmbx.UUCP (Johann Deutinger) (01/08/91)

In article <2104@beguine.UUCP> Rob.Wedlock@samba.acs.unc.edu (Rob Wedlock) writes:
>Hi... I was wondering if there is a protocol for FAX transmissions, i.e.
>i?s there anykind of inquiry I can send to it to recive back it's model
>or parameters? Or is it more of a dumb terminal???

(This might better be placed in comp.dcom.fax or alt.fax)
Yes, there is a protocol for fax transmission. When you call a fax machine
it responds with an answer tone (3 seconds 2100 Hz) and after that it sends
you one or more HDLC-formatted blocks using a 300 baud V21 transmission mode.
(You can hear it when you call a fax machine by phone). These blocks identify
the called machine's capabilities, like possible bit rates, resolution,
minimum time per line and others. Optionally it also identifies the
manufacturer and country of origin. You may find all that information
in the CCITT T30 specs.


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