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Basic phone

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Charlie123

New Member
Hello everybody :)

Please somebody can provide me just a hint on this issue;

few days ago I asked a question regarding MT8841(caller id).
I did make some very interesting progress due to your site, actually people here answer the questions.

The answer is not always straight foward because they are not easy to answer but did help me a lot in my research.

But I have a very good question regarding FSK. As per what I rode, this MT8841(caller id) is providing FSK signal out (data) on 3 pins. Some site provide me answer regarding the message itself;

--------------------------------------------------------------------------
The signal of a CALLER ID looks like that:

04 12 30 39 33 30 31 32 32 34 36 30 39 35 35 35 31 32 31 32 51

04h= Calling number delivery information code (message type word) 12h= 18 decimal; Number of data words (date,time, and directory number words) ASCII 30,39= 09; September ASCII 33,30= 30; 30th day ASCII 31,32= 12; 12:00 PM ASCII 32,34= 24; 24 minutes (i.e., 12:24 PM) ASCII 36,30,39,35,35,35,31,32,31,32= (609) 555-1212; calling party's directory number 51h= Checksum Word

--------------------------------------------------------------------------

My question is: How can I filtered only the phone number and discard all the other information that I don't need ? In this case, phone number 609 555-1212 looks like: 36,30,39,35,35,35,31,32,31,32 :eek:

Or is there any other way to make a phone answering automatiquely let say after 5 rings ? Do you suggest something else to make the phone ansewered automatiquely ?


A hint will be appreciate a lot. Tks.
 

Brevor

Member
I would save the whole message string (21 bytes) to internal ram as it is received byte by byte. Then go back and pick out and display only the data I am interested in (bytes 11-20 decimal) Which is the phone number.
 
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