[Asterisk-Dev] single bit T1 errors (Zhone again)

[Jon Pounder]

Thanks Don,

You saved me a bit of math - I understand the basics of how the signalling 
works, but as you, I am also unsure of whether the events in the driver 
represent every bit that comes along, or just the changes in state of the bits.

I know there are a bunch of other people on the list with zhones, am I the 
only one plagued with these issues, or has everyone else just tossed theirs 
in the garbage or what ?


At 04:50 PM 4/15/2003 -0500, you wrote:
>On Tuesday, April 15, 2003 3:28 PM, Jon Pounder [SMTP:JonP at inline.net]
>wrote:
> > 1) does every signaling bit that comes along generate an event in the
> > driver, or only the first bit of a given signaling type (ringing,
> > hookstate, etc.) ? If so great, if not what handles this part ?
>
>I don't know if this is useful information as it is not driver specific
>but is T1 specific. Framing and channel configuration have an effect on
>signaling states. A signaling state is determined by looking at a
>complete superframe, which will contain 2 or 4 signaling bits.
>
>If framing on a T1 is
>ESF -
>     4 signaling bits A, B, C and D (16 possible state) -
>     superframe is 24 frames long. Signaling come from frames 6,12,18,24
>SF -
>     2 signaling bits A and B - (4 possible states)
>     superframe is 12 frames long. Signaling bits come from frames 6 and
>12.
>
>
> > 2) do the events in 1) come in at a reliable interval as defined by
>the
> > media properties eg: T1 would have a certain fixed event rate per
> > channel, and E1 would have another predictable but possibly different
> > rate ?
>
>There would be a reliable interval for the state of a T1, one
>superframe. One frame is 1/8000 of a second (125 micro second). So
>every 1/8000 second there could be a new state.
>
>I have no idea how the driver passes on signaling. It could be bits or
>states or change in states. Also, I do not know if there is any
>performance monitoring that could be used to determine if bits are
>being received in error.
>
>If any of this is useful great, if not sorry to have used the
>bandwidth.
>
>Don Pobanz
>_______________________________________________
>Asterisk-Dev mailing list
>Asterisk-Dev at lists.digium.com
>http://lists.digium.com/mailman/listinfo/asterisk-dev