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How can I connect two computers using modem and after that sending variables!!!!!!!!!!!

NIKITA asked
Medium Priority
Last Modified: 2010-04-04
How can I connect two computers(the first one two
be on Auto answering mode and the second dials)
like when loginng in internet with modem!!!!!!!
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what kind of operating system you have ,win 95,win nt ?

For Window NT :
You can do this using Dialup networking.
on the Host machine RAS Service should be running and a user account on the host machine should have rights to use RAS



I want to connect two computers with modem(but with a delphi program)...
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sorry about it:

you are cant do something like that in delphi.
and i think that jimbob will say you the same.
if the other computers are using netware maybe there is some way.


You need to know to much about modem comunication...stuff like modem command, comm APIs, security issues (if Windows NT), overlapped issues (Windows NT) and posible multithread system...

some Win32 APIs to access the comm port are:

To create to application that comunicate over modems you need that the receiving programm stay on memory (locking the comm port) at the moment of receiving the call, the calling programm need to send some special character to tell the modem that made the call...

some command characters are:
   ATDT  (to dial in tone mode)
   ATDP (to dial in pulse mode)
   +++    (to hangup the phone)
   ,         (to sleep modem during 2 second)

and example is...    ATDT,1564845      this sample just dial the phone number 1564845

be carefull with modem command because there are some standard but some modem have its own commands... so read your modem documentation...

if you want to lose your dreams in an space of MS APIs... try TAPI (Telephone API)... but I do not recomend you that because that is another non-standard MS calls...

don't give up, but there are a world of comm issues...


saar thas was a chrismas gift...     ;-)


I know how to dial a number with createfile and writefile
but I can't connect them!

The dial is easy, the receiving is not so ease, but the modem connection is automatic... then you just need to turn in command mode... and BINGO everi thing that you send should be received in the other computer...

be carefull with the way that you call CreateFile, in read and write mode and be carefull to of the overlapped issues tha will affec your system in NT environment...

good luck...
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