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Dtmf 8870

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41 Threads found on Dtmf 8870
Hi, I have written a C code using CodeVision AVR and Tiny2313 to detect dtmf tones using 8870 and turn on the relay if any of the valid code is found. Code is as followsm, #include #include #define EST PIND.1 #define STD PINA.1 #define Q4 PINA.0 #define Q3 PIND.2 #define Q2 PIND.3
Hi, I want to design 2 digit dtmf decoder using 8870 dtmf decoder. Means 00 to 99 should be displayed on two 7 segments. No use of microcontroller.. Using one 7 seg display is quite easy but how to do it with two 7 segment display. CAn anybody suggest some rough schematic.
I know that we can control the output connected to the 8051 ports through mobile by interfacing dtmf decoder 8870 with 8051 .....but can i get information of some inputs connected to the 8051 to my mobile by interfacing any other device with 8051??..... if yes ,please help me out by informing about that device.......?
HI FRIENDS NOW AM INTERFACE 8870 WITH NOKIA 2310 CELL PHONE i check dtmf 880 q1,q2,q3,q4, outputs are working pressing all keys on only that mobile only and not working remote operation another mobile why.............??? am using c1=0.1uf, r1=10k, pin 2 r2=10k , pin 3
Hello sir what is the basic use of CM 8870 i.c. , what we call it ? Seems it is related to sound work , please explain in very short Its dtmf decoder (receiver), decodes dual tones and . IC id is 8870 and CM is manufacturer, also there is other manufacturers of this IC with other prefix to 887
i was working on dtmf decoder(MT 8870) lately and during that time i found that it was giving proper o/p on galaxy fit but not able to decode and give o/p on galaxy Y.Just try to plug in the device which gives you undesirable output and make a call from which you are getting correct output. P.S when you jack in aux wire make sure your phones media
Circuit is bad, what you plan with thise diodes on output ? See circuit examples : www.radiolocma
i used 8870 i connect the hand free to 8870 i press key it not generate any out put i check crystal frequency it is 2.9MHz so i replace the crystal but problem still remain then i replace both capacitor of 33pf & crystal but problem sill remain i change ic 8870 with a ic 8870 which work in other circuit but the (...)
Its possible. Almost every GSM phone can generate dtmf codes. But why to use dtmf codes, you need to establish connection, you can use SMS control.
Please I urgently need a working circuit and source code for a dtmf(eg.8870) and AT89S52 to control 4 relays(ON and OFF as desired) connected on Port2 of the AT89S52. The dtmf should be fed to port3 of the AT89S52. The Relays should be turned ON by the pressing of keys 1,2,3 and 4 respectively but can be Turned OFF by ke
as a part of project i had connected mobile to dtmf Decoder Works Well(gives Output for all switch pressed ) But when I Make A call From Another Mobile to the mobile that is connected to dtmf DECODER It Only gives output for pin Number 3 6 9 What Shoud Be the Reason? I have Also Tried after Changing Mobile...... Please Reply if Any One have Exp
The service provider of the GSM has nothing to do with dtmf tones which are generate dby your handset. If you are connecting your cellphone headsets to the dtmf decoder with 8870, Note that some headsets doesnt use ground from the cellphone and your dtmf decoder needs a ground as reference. Cross check the headset (...)
I want to interface 8870 dtmf ic with 8051 what is the program for ....this when we press 1, 2... like this thankyou Can be more specific ? You need to decode dtmf using 8051 and show number on 7-seg LED or LCD ? Interfacing 8870 dtmf decoder with 8051
I want to interface 8870 dtmf IC to uC 8051..... problem is output of 8870 is binary and how to program 8051 for a binary input. as I want, when i press 1 2 3 from my cell phone the relay is latched,and again when I press 3 2 1 that get back to its original position.. Please help for this problem...
I will be designing using MT8870 dtmf detector and using the HT9200 dtmf Generator both use AT89C51 ..... I have made it alone detector and generator run ,, the results ok .... I want to combine both, but the code that I made did not work .. please help me in troubleshooting the code just use asm ;**************************************
Hello everybody I want to design and make a ID caller with 8870 and 8951 and LCD . please help me to makes code ASM for conversi dtmf to LCD
i m making project on dtmf decoder and i am unable to get output through my mt8870 ic .i have tried different gain by changiing resistor values between ppin 2 and pin3.but still no breakthrough in the circuit. please help me out.
The outputs are all low if 'E' is high so you must pull it low if you want anything on the output pins. 'EL' enables the data into the latches when it is high and holds it there when it goes low. You can connect it to the 8870 'Std' output so you get one of 16 outputs which go active (high) when a dtmf tone is received and stay active until a diffe
Just check this old reply for dtmf decoder query Regards Chanchal
They are nothing more than tone decoders. If the tones are present in the on-hook state and you have suitable coupling to the line, they will work. dtmf decoders normally have on-board bandpass filters to ensure only the high and low tone groups are monitored, other tones on the line will be ignored. Brian.
how can we make a dtmf reciever circuit using cm8870. the transmission is through fm. When the transmission is through FM, use a FM receiver and connect its output to the input of the 8870 decoding circuit. Construct it as per given in the datasheet. Cheers
Hi post reader! For my final year project i am building an interactive voice response system that uses the ICS 8870 for decoding dtmf, rs232 n max 232 for serial communication and 8951 microcontroller for call detector n etc.. It would be very helpful to my cause if anyone could tell me of any such existing small scale ivr implementation... :)
which dtmf IC you are interfacing?? for a 8870 DTME decoder it gives 4 o/p Q1,Q2,Q3 & Q4 and based on that compare it with the table given in the data sheet you will come to know which key is been pressed and you want the whole coding.... :? why not just try yourself and then asks to remove the problems
hi corner_boy it may be of phone line noise on college campus or using with bad PCB listen to sound of there phone line check it's noise or maybe the generated dtmf is not clear or weak if it's be weak U should change to resistor of input of 8870 to change it's input gain be success
hello..... is the DTMR decoder IC 8870 or 9170 is available in ORCAD??? can any one tell me where it is which libraby..........??? thanku.......
It is about 8870, not in detail. Hope it helps.
i am using dtmf IC 8870 in my circuit............but this IC is not there in proteus 7.1 library........does any one have this IC......or can anyone help me find this IC........its an integral part of my circuit.........
i am using dtmf IC 8870 in my circuit............but this IC is not there in proteus 7.1 library........does any one have this IC......or can anyone help me find this IC........its an integral part of my circuit.........
hi body with 8870 just U can have caller ID in dtmf if U want a full caller ID U should use 8843 too (if U want it as a project contact me "" ):D:D also see this
hai i had made a remote control using dtmf . but how to make o/p of 8870 to 0000 on power up . it is giving jung values on power up
you can apply your audio input between dtmf input and GND as shown in the image
how do i decode the dtmf tones in a cellphone?? i found many circuits on net where one can decode telephone dtmf tones using 8870 using the same ic to decode cellphone dtmf ..does it require any change in the circuit??? circuit link: can i use the same circuit???
Hi, I wanna design a multi channel dtmf decoder, I wanna decode 3 phone lines, but the problem is how can I make it without putting the same ground for each line. Cause when i put the same ground any change on any line appears on the 3 8870 output. so can you pls help me?
hi anyone know which simulation software has dtmf 8870 ic in its parts list? or which simulation software support 8870 ic. these software don't have this ic in its parts list: 1 multisim 9 2 tinapro 6 3 proteus 4 saber designer pls help orak
is there any software simulation program to simulate simple projects on 8870 dtmf. multisim and circuit matker don't have spice model for 8870. thanks for reply
is there any software simulation program to simulate simple projects on 8870 dtmf. multisim and circuit matker don't have spice model for 8870. thanks for reply
Hi, check this link: i hope that i gave you right link
Hai I am using 8870to decode a dtmf tone from a telephone line. But the decoder always out a different value. for 2 it outs 3 for 4 it outs 5 That means the LSB of the data line always come as 1. I checked the line for any short or anything like that. Any idea? Anything to do with gain of 8870 (...)
Hi This is a complicted project since you will need to decode dtmf (use 8870 to do that ) read it into a ucontroller and have the ucontroller generate Bel202 protocol data using the uart , Send the data to XR2206 FSK modulator and you got a sulation ! All the best Bobi
I need circuit diagram for dtmf. Thanks USMAN HAI
Maybe you can post your code here, might be a problem with a misconfigured I/O pin of your pic. Also post which pin of the dtmf chip is connected to which pin of your pic. best regards