How can i provide faster return line from my modem when the line is BUSY ?

Most modems _immediately_ respond to a "busy" condition.
What make & model is your modem,
e.g., Cardinal or US Robotics or IBM,
Connecta X2 or Sportster Winmodem 33.6 or LT.
More details about your modem, please.

My modem is GVC 14400 bps V32.bis

After you hear the telephone "dialing" the seven digits,
then how many seconds later do you hear the "busy" signal
sent out by the telephone company?
How many seconds later does the modem report 'BUSY' ?

Does your modem support fax? Most fax modems will return busy a little slower than non-fax modems.

It's a FAX MODEM and after dialing the number  5 more sec. then "BUSY"

If 5 seconds is not "fast" enough for you,
how many seconds would be "fast" enough?

Yes, it's not. Once I don't know how, I was playing with VBPRO4 and i made it to returno "BUSY" in 3 seconds :-). I'm serious.
THank you for the BAD news :-)

Adding X4 (ie ATX4Dphone-number) to your modem initialization returns all error codes as quickly as possible.  Modems have to wait a certain length of time to be able to distinguish a busy signal from voice or data negotiation.  If you turn on the modem speaker (ATM1L3), typically you should hear two busy signals before the modem disconnects with the BUSY response.

Sorry BUT my telephone company does not recognise X4, (When dialing "NO DIALTONE")
I'm using X3 Init.

The 'ATX4Dnnn-nnnn' is sent to your modem,
not to your telephone-company.

Your modem should "execute" the 'X4' command,
and the 'D' command.

The 'D' command will wait for a "dial-tone"
from your telephone-company, and then will send the
touch-tones for 'nnn-nnnn' to your telephone-company.

Does the reference-manual for your GVC modem
indicate that the 'X4' command is recognized?

When I add ATX4 the modem response is "OK" But then when i dial the response id NO DIALTONE

 

> when i dial the response id NO DIALTONE

If you plug a normal telephone into the port,
and pick up the receiver, do you hear the dial-tone?
If not, then your modem is also not hearing the dial-tone.

To Otta: The differnce between ATX3 and ATX4 is that atx3 only checks for busy and atx4 checks for busy and no dialtone. This has nothing to do with Crazycray's question.

I don't think that there wll be a standart hayes command for setting this time because it depends on the time your phone company needs to check for the busy line too. What time to you need when you call a number manualy to check a line is busy?

I do not understand quite your answer ! :-(

My p.company returns the BUSY(beeping)signal in a moment, but my modem needs a 5 seconds to understand that signal(beeping)

I'll be satisfied if i recive a return in 2 or 3 sec. But 5, that is too slow for me.
P.S. I have an TONE Dialing.