Re: The PABX works!

[Pete Shew <ukha_d@xxxxxxxxxxxxxxxxxx>]

Frank,
the PICs are 16F877 - I was using a EPE PICSTART chip, but I've also
used the MPLAB ICD (1)  - and a 16F84. The 84 is doing tone generation
for the call progression tones. The original FS2828 only used a single
tone,, and it was one of my hates. It only uses three output levels -
output 0v and 5v or input high impedance with value set by a voltage
divider at 2.5v. 350+450Hz and 400+450Hz  signals sound surprisingly
like BTs.

The 877 does everything else. There are a bunch of input buffers and
output latches connected to a bus on port D and individually selected by
port E and port C pins. The existing cross point switch and the DTMF
decoders are also on the Port D bus. There is a 20mS interrupt that
detects changes in line and extension status etc, and is used to output
and input DTMF tones. The main routine checks for things to do and
housekeeps unused resources like DTMF decoders and resets unused
extensions. There is also a doorbell checker as that was one of the
things I really liked from the FS2828, The house is quite large and you
can't hear the doorbell very well , so all the phones ring in a triple
cadence when the doorbell is pushed, including when little sh*ts walk
past and press the bell..

Features include conference, call transfer, call park, short code dial,
intrude (this is a domestic installation), and automatic external call
detection (if a number starts with 0 it must be external - why dial 9).

Pete

Frank Mc Alinden wrote:

>Hi Pete
>            Nice Pics ...... I assume the little boards at the bottom
are
>your addon micros (16f877) ?
>What do they actually do ???
>Frank
>
>
>----- Original Message -----
>From: "Pete Shew" <ukha_d@xxxxxxx>
>To: <ukha_d@xxxxxxx>
>Sent: Monday, November 29, 2004 9:12 PM
>Subject: Re: [ukha_d] The PABX works!
>
>
>
>
>>*OK - http://tinyurl.com/5mgpz
>>
>>Pete
>>*
>>Frank Mc Alinden wrote:
>>
>>
>>
>>>Hi Pete
>>>
>>>It works! My rebuild of my PBX is working fine and better than
before.
>>>
>>>
>>>
>>>
>>>>My Omnicom FS2828 died so I lobotomised it and threw a
couple of PICs at
>>>>it and now it does a better job than before
>>>>
>>>>
>>>>
>>>>
>>>PICS ;-)))
>>>
>>>Frank
>>>
>>>
>>>----- Original Message -----
>>>From: "Pete Shew" <ukha_d@xxxxxxx>
>>>To: <ukha_d@xxxxxxx>
>>>Sent: Monday, November 29, 2004 8:08 PM
>>>Subject: Re: [ukha_d] The PABX works!
>>>
>>>
>>>
>>>
>>>
>>>
>>>>It works! My rebuild of my PBX is working fine and better
than before.
>>>>My Omnicom FS2828 died so I lobotomised it and threw a
couple of PICs at
>>>>it and now it does a better job than before. A much better,
to my mind,
>>>>human interface for domestic use then the original.
>>>>
>>>>I felt I had to share my feelings of success :-)
>>>>
>>>>OK - I know everyone is talking about VOIP these days, but
VOIP phones
>>>>aren't cheap and they are overkill for the purpose.
Asterisk would have
>>>>been nice, but the FXS interfaces are too pricey. My
answerphone uses a
>>>>Dialogic card in a Windows PC with RYO software to email
messages.
>>>>
>>>>What I need to do now is to link the answerphone to the PBX
to allow
>>>>turning on the message waiting lights, or maybe putting up
Asterisk with
>>>>a link to the PBX.so I can use Asterisk Answerphone and
VOIP routing
>>>>features. It would have to be a jigged FXO card though
because they're
>>>>cheap, like me.
>>>>
>>>>Onwards ...
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>Yahoo! Groups Links
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>Yahoo! Groups Links
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>>>
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>>>
>>>
>>>
>>>
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>>Yahoo! Groups Links
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>Yahoo! Groups Links
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