applications of dtmf - Electronic Circuits Projects Diagrams Free

simrantogether · 5th September 2007, 06:05 AM

I searched many threads.. but i didnt got the applications of Dtmf..

I have the tutorial and interfacing circuit diagram..

but i wanted to know its various applications..

Please post your ideas and knowledge..

Regards,

Simran..

**Nigel Goodwin** · 5th September 2007, 08:09 AM

Quote:

Originally Posted by simrantogether

I searched many threads.. but i didnt got the applications of Dtmf..

I have the tutorial and interfacing circuit diagram..

but i wanted to know its various applications..

Please post your ideas and knowledge..

It's really very old technology (40 years?), it's still used for what it was designed (dialing phone numbers) - pretty well anything else was replaced by digital methods decades ago.

Gayan Soyza · 5th September 2007, 08:13 AM

Hi Simran DTMF (8870) testers are all over the web.

Try searching MT8870 DTMF tester.In india Also I saw many projects done with this IC interfacing to a micro controller.Its very easy.

simrantogether · 5th September 2007, 08:16 AM

Thanks ...

it's good if we can dial the phone numbers.. using microcontrollers...

1. can it be used for generating number of phone lines... from one line..

2. can it be used for controlling from Long diatance like 100 kms through phone..

3. Dual tone means.. ? and multi frequency means.. ?

actually i was thinking for applications point of view and hobbyists can help most in this...

Regards,

Simran..

simrantogether · 5th September 2007, 08:19 AM

Quote:

Originally Posted by Gayan Soyza

Hi Simran DTMF (8870) testers are all over the web.

Try searching MT8870 DTMF tester. Its very easy.

Is DTMF tester same as dtmf applications like decoder..

here ' tester ' means..

Actually the tutorial i'm following is:

http://www.freewebs.com/maheshwankhede/dtmfdecoder.html

Regards,

Simran

Gayan Soyza · 5th September 2007, 08:36 AM

MT 8870 is a DTMF tone decoder IC.Yes its a similar project.

When it hears a valid tone pair it starts counting binary & showing by the 4 bits.By this 4 bits its giving input to the micro & detecting what inputs have come.So it can determine which output to be turn on or off.

simrantogether · 5th September 2007, 08:50 AM

that means :

it counts from ' 0000 b ' till ' 1111 b' in binary form in an infinite loop ...

and suppose when we pressed any key suppose '5' then it after detecting '5' gives it to microcontroller...

Am i right?

Regards,

Simran..

Gayan Soyza · 5th September 2007, 08:58 AM

Yes when you press number 5 it will show b’0101’ from the 8870 outputs. If you connect 4 leds to the output of 8870 you will see the first & the third leds will lights up when you press five.

So we are writing a program inside a microcontroller if this value b’0101’ has come to the micro then turn on the fifth relay.

If you press number 1 then it will display b’0001’ so you tell micro if bit 0 has set then turn on relay one etc……

simrantogether · 5th September 2007, 09:03 AM

Hey Gayan.. Its wonderful...

One very important thing i would like to ask from you..

Can we use DTMF 8870 for making our " keypad " because usually.. what we see is that the algorithm of general keypad is tough..

I think you might have followed the book called Mazidi and Mazidi.. that keypad algorithm is tough..

Regards,

Simran..

Gayan Soyza · 5th September 2007, 09:10 AM

Quote:

Originally Posted by simrantogether

Can we use DTMF 8870 for making our " keypad " because usually.. what we see is that the algorithm of general keypad is tough.

You can but incase if the steering pin if wont go high it wont make any outputs from 8870.So better make a keypad without taking DTMF.

For me DTMF is better to control device in the vicinity.

simrantogether · 5th September 2007, 09:15 AM

Thanks Gayan.. for frequent answers...

Regards,

Simran...

**Nigel Goodwin** · 5th September 2007, 09:46 AM

Quote:

Originally Posted by simrantogether

Can we use DTMF 8870 for making our " keypad " because usually.. what we see is that the algorithm of general keypad is tough..

Scanning a matrix keypad is really pretty easy, easier (and a LOT cheaper) than using DTMF - which would really be a silly way to do it.

simrantogether · 5th September 2007, 12:21 PM

Actually the keypad i am using ..

Sir, i find it a bit tough...

just for detecting one key out of 16 keys.. it takes a very big program in ' c language '.

but then also i'll try...

Regards,

Simran..

**Nigel Goodwin** · 5th September 2007, 12:36 PM

Can't help you specifically on 8051, but my tutorials show how to do it in PIC assembler - exactly the same principles apply though, no matter what the processor, or language.

simrantogether · 6th September 2007, 05:11 AM

Sir yes..

I'll definitely try ..

Actually, i needed some help ...

if possible .. please answer the following questions:

1. can DTMF be used for generating number of phone lines... from one line..

2. can DTMF it be used for controlling of stepper motor from Long diatance like 100 kms through phone..

3. Please tell the name of the example project that can be made on interfacing DTMF with controller..

Regards,

Simran..

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Latest
Visual Basic for Electronics Engineering Applications	ThermalRunaway	Electronic Books	22	27th August 2008 07:40 PM
Could anyone tell me where I might find a DTMF decoder IC?	Micah	Micro Controllers	10	16th August 2007 12:26 AM
dtmf applications??	msovais	Electronic Projects Design/Ideas/Reviews	9	23rd February 2007 10:49 PM
DTMF decoder, please help!!	mindctrl	Electronic Projects Design/Ideas/Reviews	3	18th July 2005 05:16 PM
DTMF decoder with MIC	KaJuan	Micro Controllers	0	16th February 2004 07:53 AM

5th September 2007, 06:05 AM	(permalink (permalink))
simrantogether	applications of dtmf I searched many threads.. but i didnt got the applications of Dtmf.. I have the tutorial and interfacing circuit diagram.. but i wanted to know its various applications.. Please post your ideas and knowledge.. Regards, Simran.. __________________ Simran.. 8051 Specialist..

5th September 2007, 08:13 AM	(permalink (permalink))
Gayan Soyza	Hi Simran DTMF (8870) testers are all over the web. Try searching MT8870 DTMF tester.In india Also I saw many projects done with this IC interfacing to a micro controller.Its very easy. __________________ Gayan My Website http://gsmicro.blogspot.com/

5th September 2007, 08:16 AM	(permalink (permalink))
simrantogether	it's good.. Thanks ... it's good if we can dial the phone numbers.. using microcontrollers... 1. can it be used for generating number of phone lines... from one line.. 2. can it be used for controlling from Long diatance like 100 kms through phone.. 3. Dual tone means.. ? and multi frequency means.. ? actually i was thinking for applications point of view and hobbyists can help most in this... Regards, Simran.. __________________ Simran.. 8051 Specialist..

5th September 2007, 08:36 AM	(permalink (permalink))
Gayan Soyza	MT 8870 is a DTMF tone decoder IC.Yes its a similar project. When it hears a valid tone pair it starts counting binary & showing by the 4 bits.By this 4 bits its giving input to the micro & detecting what inputs have come.So it can determine which output to be turn on or off. __________________ Gayan My Website http://gsmicro.blogspot.com/ Last edited by Gayan Soyza; 5th September 2007 at 08:39 AM.

5th September 2007, 08:50 AM	(permalink (permalink))
simrantogether	that means.. that means : it counts from ' 0000 b ' till ' 1111 b' in binary form in an infinite loop ... and suppose when we pressed any key suppose '5' then it after detecting '5' gives it to microcontroller... Am i right? Regards, Simran.. __________________ Simran.. 8051 Specialist..

5th September 2007, 08:58 AM	(permalink (permalink))
Gayan Soyza	Yes when you press number 5 it will show b’0101’ from the 8870 outputs. If you connect 4 leds to the output of 8870 you will see the first & the third leds will lights up when you press five. So we are writing a program inside a microcontroller if this value b’0101’ has come to the micro then turn on the fifth relay. If you press number 1 then it will display b’0001’ so you tell micro if bit 0 has set then turn on relay one etc…… __________________ Gayan My Website http://gsmicro.blogspot.com/

5th September 2007, 09:03 AM	(permalink (permalink))
simrantogether	Hey Gayan.. Hey Gayan.. Its wonderful... One very important thing i would like to ask from you.. Can we use DTMF 8870 for making our " keypad " because usually.. what we see is that the algorithm of general keypad is tough.. I think you might have followed the book called Mazidi and Mazidi.. that keypad algorithm is tough.. Regards, Simran.. __________________ Simran.. 8051 Specialist..

5th September 2007, 09:15 AM	(permalink (permalink))
simrantogether	thanks.. Thanks Gayan.. for frequent answers... Regards, Simran... __________________ Simran.. 8051 Specialist..

5th September 2007, 12:21 PM	(permalink (permalink))
simrantogether	Actually the keypad .. Actually the keypad i am using .. Sir, i find it a bit tough... just for detecting one key out of 16 keys.. it takes a very big program in ' c language '. but then also i'll try... Regards, Simran.. __________________ Simran.. 8051 Specialist.. Last edited by simrantogether; 6th September 2007 at 05:11 AM.

5th September 2007, 12:36 PM	(permalink (permalink))
Nigel Goodwin	Can't help you specifically on 8051, but my tutorials show how to do it in PIC assembler - exactly the same principles apply though, no matter what the processor, or language. __________________ PIC programmer software, and PIC Tutorials at: http://www.winpicprog.co.uk

6th September 2007, 05:11 AM	(permalink (permalink))
simrantogether	Yes sir.. Sir yes.. I'll definitely try .. Actually, i needed some help ... if possible .. please answer the following questions: 1. can DTMF be used for generating number of phone lines... from one line.. 2. can DTMF it be used for controlling of stepper motor from Long diatance like 100 kms through phone.. 3. Please tell the name of the example project that can be made on interfacing DTMF with controller.. Regards, Simran.. __________________ Simran.. 8051 Specialist.. Last edited by simrantogether; 6th September 2007 at 05:48 AM.