ISDNTELCTL(8) MidnightBSD System Manager’s Manual ISDNTELCTL(8)


isdntelctl — control isdn4bsd telephone sound format conversion


isdntelctl [−c] [−g] [−u unit] [−A] [−U] [−N]


The isdntelctl utility is part of the isdn4bsd package and is used to configure the sound format conversion facilities of the /dev/i4btel interfaces.

The following options are available:


Clear the telephone input queue.


Get the sound format currently in use.


Set the /dev/i4btel unit number. The default value is zero to access device /dev/i4btel0.


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


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


Set sound conversion to do no format conversion.

The telephony data stream comes out of the line in a bit-reversed format, so the i4btel(4) driver does the bit-reversion process in any case.

Additionally, the user can specify to do A-law to u-law, u-law to A-law or no conversion at all in the i4btel driver by using the isdntelctl utility.




The command:

isdntelctl -g

displays the currently used sound format for device /dev/i4btel0.


g711conv(1), i4btel(4), isdnd.rc(5), isdnd(8)


A-Law and u-Law are specified in ITU Recommendation G.711.


The isdntelctl utility and this manpage were written by Hellmuth Michaelis 〈〉.

MidnightBSD 0.3 April 21, 1999 MidnightBSD 0.3