Pulse Dialing through Software

[talent]

w can some one please help me out on the issue of Pulse Dialing...

like for DTMF iam using MT3271 which decode the number .

But for Pulse Dialing can i use the same off-hook detection path to sent Pulses of dialing to controller using the theory that if "1" is pressed 1 pulse goes to controller if "2" is pressed 2 pulses...and if 0 is pressed then 10 pulses...
For this can i use :-

Like if i take:-

Make / Break ratio as 60:40 micro-seconds

and Inter Digit Space as 800 milli seconds..

how will i detect Pulses from telephone viz SLIC.

Suppose MT8816 X0 gets connect with Y0 if digit 0 is dialed if any other digit is dialed nothing happens.

what adjustment should be made in the following:-

should i use any interuppts of timing coz if i use the following software can only enterain one telephone set dialing...

MOV R0,#0D ; "initial value in Pulse Counter Register"

AGAIN:
JB P1.0,$ ;waiting for pulses to come on the same bit where off-hook is detected
Inc R0
JNB P2.1,$ ;waiting for low
CJNE R0,#02D, AGAIN ; "detecting whether the dialed number is 2 or not, if 2 then its desired function is done other wise controller wait for pulses"
SJMP MT8816_ADDRESS

using At89c51 & Crstal of 11.05 KOH

 

[vik1501]

I have worked a lot on telecom.

Whats the status of ur project


May be I can help u if u give me feeback, as this seems to be quiet old querry

 

[lee_man_tbu]

Phone Line Interfacing

Vik1501:

Hi,

I noticed from your reply that you have done lots of work with Telecom and i was wondering if you woud you know of a simple circuit that i could use too connect a PIC and MT8880c DTMF Decorder too a Phone line. I am not interested in dectecting rings, i just want too use the pic to make the on / off hook and dial a phone number, then once the person at the other end hold down a single key and i will receive that. Alos, i need a speaker at the PIC end of the application.

any help you have on this would be great.

I have a circuit that i think will work, but i don't want too go get the parts untill i am sure. I can e-mail you that circuit if that will help...
Thanks

lee

P.S.
If you want too e-mail me that would be great

lee_man_tbu@hotmail.com