I have been trying to figure this out, but can't find much on it. I was wondering if anyone knew of away to to tell if a phone is ringing, and how to get caller id info. I believe I would need some DTMF IC, but can't figure out what would be right. If anyone has any sites and/or suggestion, please I am welcome to reading as much as possible to figure this out.
There's a nice simple description of ringing here. There are some good descriptions of other signals, and how to do your own interfaces, here. You can also find examples of DIY caller ID circuits online.
Note the warning about legalities: it's unlikely that anything you build will draw the ire of your local phone company, but it's your responsibility.
It wont deal with anything with the phone company, I am just wanting to figure out how to build something for my phone at work to have on screen display and stuff when my phone rings and who calling it, because I can't stand the ringer and I always have headphones on. Thanks by the way Ill check these out, and hopefully they will give me a good start on building this.
It is encoded in the old-fashioned Bell 202 FSK modem format and sent between the first and second rings.
And if you really want to know how it works and how to use it, there have been tons of articles on the subject published by these fine folk:
You will, of course, have to buy back issues or something...
If you don't want to do that, then you might have to do some research in this realm to find useful answers; a lot of legit information can be found online, but the some great information can be found in the phreaking community.
Note that such research may get you put on a list somewhere (and if you weren't aware of this already, then you likely shouldn't look)...
Okay thanks, I don't have the model of the phone system, but the phones are Lucent MLX-10DP, and been researching Bell 202 and FSK and came across this chip EM92547A which looks promising.
Ah okay, so is there away to get the information it sends? I know a regular phone can put oh the line and it works, but I believe the CID doesn't work on it though.
Dang, thanks for the information. If I just knew of away I could read the data coming into the phone, I could possibly figure it out, but I am not sure how to even retrieve that data. 