NAME

isdntelctl — control isdn4bsd telephone sound format conversion

SYNOPSIS

isdntelctl

[-c] [-g] [-u unit] [-A] [-U] [-N]

DESCRIPTION

isdntelctl is part of the isdn4bsd package and is used to configure the sound format conversion facilities of the /dev/isdntel interfaces.

The following options are available:

-c

Clear the telephone input queue.

-g

Get the sound format currently in use.

-u

Set the /dev/isdntel unit number. The default value is zero to access device /dev/isdntel0.

-A

Do A-law (ISDN line) -> mu-law (userland) conversion.

-U

Do mu-law (ISDN line) -> A-law (userland) conversion.

-N

Set sound conversion to do no format conversion.

The telephony data stream comes out of the line in a bit-reversed format, so the isdntel(4) driver does the bit-reversion process in any case.

Additionally, the user can specify to do A-law to mu-law, mu-law to A-law or no conversion at all in the isdntel driver by using the isdntelctl utility.

FILES

/dev/isdntel<n>

EXAMPLES

The command

isdntelctl -g

displays the currently used sound format for device /dev/isdntel0.

SEE ALSO

isdntel(4), isdnd.rc(5), isdnd(8)

STANDARDS

A-law and mu-law are specified in ITU Recommendation G.711.

AUTHORS

The isdntelctl utility and this man page were written by Hellmuth Michaelis <hm@kts.org>.