This simple unit accepts user input to dial Hayes compatible modems.
The phone number may be numeric or alpha (acronyms) or a mix of both.
It is an extension of something I downloaded with no ID attached.
Bios interrupt $14 is used to send characters to the serial port.
The interrupt will return information in register ah, and al if
your interested in checking them. A good bios services reference
will contain the return codes
This should work on IBM pc's and compatibles.
If you have trouble communicating with the serial port, check and
change as needed the value assigned to register 'dl' as noted.
It selects the COM port which is connected to the modem
Number formats accepted are:
   1)  aaa-aaaa
   2)  (aaa) aaa-aaaa
   3)  aaa-aaa-aaaa
   4)  1-aaa-aaa-aaaa
   5)  1-aaa-aaaa
All other formats are rejected as invalid numbers.
The proc will insert a leading '1' prolog if necessary.
Communications ports 1 through 4 are valid.

After the modem dials and is off hook:
1. To activate the phone, pickup the phone and press [Enter].
2. If you leave the phone on the cradle and press a key, the
   modem will hang up and the program will continue.
3. If the phone is off the cradle and you press a key, the
   program will continue, and you will have control of the
   phone.


I added a few accessory routines to illustrate usage

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{ Ed Cuneo                           }
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