From: aml@world.std.com (Andrew M Langmead)
Newsgroups: comp.sys.mac.comm
Subject: Re: PD soft. for telephone pagers
Date: 28 Jul 92 21:08:13 GMT
Distribution: na
Organization: The World @ Software Tool & Die

lkimes@alshain.usc.edu (Lance 'Moof' Kimes) writes:
>This is the second time you've pointed out the obvious. I do appreciate
>any help, but I(and most people) already realize that until my modem 
>sprouts an antennae, I'm calling a 'host' that retransmits data it receives.
>So I'll restate the obvious.

From your earlier posts, it didn't seem that you had a good grasp on
what is involved. In some ways I'm still not sure. Obviously you are
joking in the above quote, but do you realize that if your MODEM _could_
sprout a _transmitter_ the only thing you would succeed in doing is
messing up the digital RF signal both you and the paging company
would send? Thebinary data for your pagers address would get mixed
up with other patrons data and both pagers would only see noise.
Paging companies bid on frequencies released by the FCC and only
one is allowed to broadcast in an area. Your pager actually sees
everyones pages, it just ignores them because they weren't preceded
by its address.

>Do all or most pagering companies use DTMF in receiving the messages 
>transmitted to the paging companies(ie: same protocal used by modems)?
>Are do they expect some special, proprietary modulated frequencies that 
>represent alphabetical characters to them? If they do, does anyone have
>C code that will instruct Hayes modems to transmite these special tones?

DTMF is only used during dialing. DTMF can only send 1-9, 0, *, #, and
a special fourth column on the touch tone pad (if your MODEM can send
them, it will use A-F.) Numeric pagers can display BCD digits (4 bits)
and display them as 0-9 and "()- E" I've never had an alpha pager to
fool with, but I'd assume th a paging host allows numeric messages
to be sent to it by dialing on a touch tone phone. Unfortunatly the
maximum of 16 chars available on the touch tone pad doesn't make 
very descriptive messages. You can't send alphanumeric data through
this options because the DTMF decoder on the other end of the
phone line can only understand the same 16 chars. (It is NOT a 
MODEM, just as the autodialer that you hear in your Hayes compatable
MODEM is not the MODEM, it is a DTMF encoder.)

>My present paging company doesn't have a tech dept that's accessible
>to those outside of their company, so they can't tell me either.
>But they do offer a software package that's works with DOS machines.
>They just don't know how it works.

THIS IS IT. THIS IS USEFUL INFORMATION THAT WILL LEAD TO A SOLUTION.
You need a method of getting your information to the paging host.

You don't want to use the Answering Service, too expensive.
You can't use the Tone port assigned to your alpha pager, it doesn't
have the bandwidth to send the messages you want.

Now there is a third way of getting into the paging host and give it
a page.

Find out the number you set up the DOS package to use. This won't be the
pager's phone number. (Which is connected to a DTMF port.)
This is a MODEM port that will speak TAP (also known as iXO.)
Call it with your MODEM. It might have a manual mode. That gives
prompts for humans. If not, the next step is to get the TAP protocol
and implement it yourself. (or to reverse engineer it from the PC version
as someone else suggested.)

>Lance Kimes
>Systems Programmer
>University Computing
>USC

-- 
|Andrew Langmead - A frustrated Mac/Unix programmer stuck in an MS-DOS job    |
|Usenet=aml@world.std.com      |S. O'Conner "We Live in a dangerous Age       |
|bix=a.langmead CI$=72411,1560 | To say how you feel is to lay your own grave"|