Caller ID

[Hesam Kamalan]

Hi,
I want to build "Caller ID" with microcontroller. but i have no any knowledg about this and telephon line characteristics. if you have knowledg, guide me please

 

[Papabravo]

Who makes your telephone system? As you might suspect, they are not the same all over the world.

 

[zkt_PiratesDen]

I know that you need to subscribe ( and pay for) the caller id service and that the display unit is often provided with the service. So I assume that you want to build one " for the fun of it". The standard way of sending data on the land line is thru DTMF- two freqs are on the line at the same time. Just which pair it is determines the which digit. Also the number that appears on the display is "probablely" sent between the ring signals which are approx 90vac. Dont mean to discourage you but this aint gonna be easy. The phone line interface has to deal with the abovementioned ring voltage and the normal -48v on the line. there are chips designed to detect the ring.GL
zkt
opps didnt notice that you ae in Iran- in that case- I have no idea how your system works- maybe same -maybenot

 

[Papabravo]

I'd be willing to bet large sums of money that AT&T(Western Electric) did not design, or build, or install the Iranian phone system. Even if they did there might be abundant reasons why they may have made a change in the last 25 years or so.

 

[zevon8]

Pretty much everywhere in the world the principle of "lets not give stuff away for free" applies in business. I'm pretty sure that unless you subscribe, the data won't be there. Caller ID add-on boxes can be had for less than 10 dollars US, the money is in the monthly fee for the service, not the hardware from China.

 

[akg]

here in india , this is a free(often default) service . the ring voltage is ~75V and coding is DTMF , which appears between the first two ring signal.

 

[fdediw]

i ever used MT88E43BE to capture FSK Caller ID.

 

[Nigel Goodwin]

Pretty much everywhere in the world the principle of "lets not give stuff away for free" applies in business. I'm pretty sure that unless you subscribe, the data won't be there.

Funnily enough I've just subscribed to "BT Privacy", I've had new phones that have caller ID built-in, so I checked how much it costs. If I ordered Caller ID there's a quarterly subscription, BUT if I ordered "BT privacy", which includes Caller ID, then it's free?. Rather bizzare I thought?, so I was straight in for the free option

 

[Paul Obrien]

Of course, if you build your own caller id unit you can choose whether or not to check for the security bit that provides the "privacy"

 

[mramos1]

In the 80 and 90's I worked for Mitel and Caller-ID was FSK between first and second ring? Maybe some Countries use DTMF now.

 

[ismetkutuk]

Dear friend anyway caller id is using microcontroller that i think it was pic series.one times i had used such thing.i was develeped so system.if you find a caller id device .you can see in it.

 

[Hero999]

I'm with NTL (and it's the same with BT), just after I 've recieved or missed a call I can dial 1471 and the computer at their exchange reads out the caller's number to me and tells me the date and time when the call was made or if they withheld thier number. This service is free but it only tells you the last call. All I would have to do is connect a microcontroller to a modem and tell it to dial 1471 after every missd call then record the message from the computer in a digital memory, it could also be used as an answer machine too.

 

[er.lovenish_garg00111]

I Also Need Help For This Project Work

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