auto dialer for security system project help

[CEstudent]

auto dailer ics

hello everyone,

im new here! and i need help , can anyone help me in how can i interface MT8888C chip with any microcontroller ( i prefer PIC) ? any thing useful ( like codes for example or documents)


Plzzzzz help

 

[CEstudent]

security system projects

any help ??

 

[dunn]

security system auto dialer project

hello everyone,

im new here! and i need help , can anyone help me in how can i interface MT8888C chip with any microcontroller ( i prefer PIC) ? any thing useful ( like codes for example or documents)


Plzzzzz help

What interface do you want to use i2c, pulse or dtmf tone dialing, terminal?

Link for Zarlink MT8888C data sheet-
**broken link removed**

Application note for interfacing to common micros-
**broken link removed**

 

[CEstudent]

What interface do you want to use i2c, pulse or dtmf tone dialing, terminal?

for dtmf tone dialing . because I’m going to design an automatic voice dialer for security system. when it is triggered, the dialer will call a specific number and play a recorded msg.


thanx alot dunn

 

[CEstudent]

hi again

i have a Question : how can i detect that the line phone has picked up or not or ( busy line ) from the other side by using ( call progress detection of MT8888 chip ) ??

because i read the datasheet and i didn't understand how to use the call progress detection


plzzzz help me in that

 

[laktronics]

Hi,
MT8888 can be used as call progress decoder, but you have to analyse the actual tone pattern in software using the microcontroller. As a standard, the tones are centered around 350 to 440 Hz and such frequencies when present on the line will be filtered out and given by MT8888. Since there is a large variation of actual tone pattern for various exhanges and PABXs, a universal tone detector is really difficult, but I think you may get some ICs from NXP Semi.

A usual practice to know automatically if the called party has gone off hook, is by looking at the 'Battery Reversal' signal or the start of Metering Pulse on the subscriber line. But unfortunately, these signals are not extended to the subsriber extensions even though they do it on special request as in the case of private telephone booths.

Regards,
Laktronics

 

[CEstudent]

Thanx alot laktronics

do u know some codes on ( Call progress detection ) that will help me to start ?

and plz can u give me more information about the IC's from NXP Semi that u maintioned

 

[laktronics]

Hi,
Please Google for Call Progress Decoder, there you can see the chip NE5900 from Phillips Semi. I do not have any codes, with this chip, you can directly get the decoded tone nibble. If you want to do the DTMF way, you have to find out in software the frequency of the incoming tones and their modulating patterns.
Regards,
Laktronics

 

[nostalgiax]

how to use mt8889

 

[abokamel]

hi,
how use atmega to generate dtmf by asm library or c
thank you very much

 

[pak_jang]

hi,
anybody know which one better use ic, mt8880 or mt8889.
what are the different??

 

[rajudp]

if you are using micro controller you can use DTMF generator with software

 

[pak_jang]

yes i my project using PIC16f877 microcontroller.
how i want program it?? are u have source coding?? plzzz

 

[guiller]

have you guys already made the auto dialer? i need to make one also.. any help?

 

[tpetar]

https://www.elektronika.ba/505/phone-call-alert/

For voice use some voice specialized IC.

600R : 600R isolation transformer and small 5V relay remove from some old modem.


DTMF also can be generated by PWM of PIC or AVR.