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Using BS2 to dial a cell phone — Parallax Forums

Using BS2 to dial a cell phone

manzanamanzana Posts: 24
edited 2008-12-29 19:24 in BASIC Stamp
Has anyone tried this with the DTMF outputs? It would be mighty handy for remote communication. Maybe get a cheap trackphone and hook up a BS2 to phone home. Thanks for any input. STAMPS RULE!·· smilewinkgrin.gif·· manzana in Texas

Comments

  • FranklinFranklin Posts: 4,747
    edited 2008-12-18 03:37
    I don't think most cell phones use DTMF for dialing any more. You might have better luck hacking the hardware to simulate the pushing of the buttons.

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    - Stephen
  • manzanamanzana Posts: 24
    edited 2008-12-19 23:45
    Right you are Franklin. I bought a TracFone at Walmart for $10 just to rip it apart. (They hate people who do that!). Looks like a no-brainer. If you peel away the membrane which the metal buttons are on - bingo. You have a matrix of copper pads which beg to have wires soldered to them. (Use a low wattage iron like 15 watts). It would be perfect to interface to a BS2. Some resistors might be needed on each one to adjust voltage levels but that should be all. The BS2 could power on and off the phone, dial any number and even send text messages. Pretty awesome for $10 plus air time of course. Your BS2 could call anywhere on the planet. Will post further developments...



    manzana in Franklin, NC
  • azmax100azmax100 Posts: 173
    edited 2008-12-20 02:46
    Hi manzana.

    I woulk like to see the schematic how·you are going to connect the BS2 to the phone button. I am on a project·of using my old h phone mp3 player for robotic voice.I am using relay for the button. Still under construction. I will let you know the outcome too.
  • manzanamanzana Posts: 24
    edited 2008-12-20 13:31
    I probably wont get to try this for a couple of weeks but I just intend to tie each button to one output of the BS2. Then just press the button by issuing HIGH or LOW commands to the appropriate pin. You could do anything you wanted with the phone. Things to consider:

    1. Each button has 2 contacts, an inner circle an an outter ring. One of them is common to all the buttons. Need to determine if the button is grounded or at some voltage when it is closed. This is what the BS2 needs to duplicate. It may take a resistor or 2 to do this.

    2. The keypad is close to an RF source which will interfere with the wires you solder (maybe). If it does it is best to use small coaxial wires to go to the BS2 and put a high frequency cap (maybe 12 pf?) at the phone side. This might be not be necessary. Not sure.

    3. I think your stamp will want to test if the phone is on or off too. You dont want to lose track of this if the phone is in a remote location. Since the power button is basically a toggle, once you got out of sync it might get expensive!

    ·3. Once the phone calls you, it needs to say something to you. It would be simple to have it text you or just put a small speaker next to the mike of the phone and send tones from the BS2 or even canned voice. My BS2 uses an RF link now and sends Morse Code. At least I am getting some benefit from 30 years of ham radio.· smilewinkgrin.gif

    manzana, Franklin, NC
  • $WMc%$WMc% Posts: 1,884
    edited 2008-12-21 01:20
    No IEDs

    Post Edited ($WMc%) : 12/21/2008 11:18:07 PM GMT
  • sam_sam_samsam_sam_sam Posts: 2,286
    edited 2008-12-21 02:26
    I think that if·I was going to do this I would use 5 volt reed relays and· simulating· the button being pushed

    This is just my 2 cent worth talking ..........>>>>>>· So take it for what it worth

    BTW most cell phones that I have used you can put the· Phone Number in first and then hit·SEND button


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    ··Thanks for any·idea.gif·that you may have and all of your time finding them

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    Sam

    Post Edited (sam_sam_sam) : 12/21/2008 2:32:33 AM GMT
  • LuXo12LuXo12 Posts: 31
    edited 2008-12-21 06:28
    Hi there i have finished a project thats just like yours, where I am using a BS2 stamp to control a cell phone, a cell phone that I am using is Samsung "Stripe" and I am able to simulate button press by activating a relay.
    The relays that I am using are <A href="http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=1582962&">LBA110</A>) Because my chip has only 16 IO pins I focused on being able to control the 5-button D-Pad and four surrounding buttons (Call, End Call, Left Select, Right Select) (rest of the pins are being used as input) with this configuration I am able to access the menu from wich I can select previously entered text message and/or telephone number.

    BTW in my program the duration of a stimulated button push is at 100 high and at 100 low.

    I hope this helps

    Good Luck on your project and let us know how it turns out
  • azmax100azmax100 Posts: 173
    edited 2008-12-22 08:51
    LuXo12 I'am having the same setting as yours to control up,down,ok,and back button. The other relay use to on and off the phone. Using multimeter I can get 2.5V from the inner ring and I assume the outer ring as ground.

    The problem is after connecting the ok and up button to the relays it's not functioning as what it should. It's works fine before connecting the second relay.

    Anything I should consider?
    ·
  • JomsJoms Posts: 279
    edited 2008-12-23 03:22
    I do not have a phone in front of me but wondering, are the buttons scanned?· Basically meaning you can't use the same comman between the relays.· If they were scanned and you were attempting to use the same common it might simulate holding down another button somewhere...· Just a wild thought...
  • LuXo12LuXo12 Posts: 31
    edited 2008-12-23 04:49
    azmax100 in my setup relays just close the circuit they don't supply power to cell phone
  • azmax100azmax100 Posts: 173
    edited 2008-12-24 05:32
    LuXo12 it's what I did. I'm using the phone battery to power it on.

    After testing all the button I get 2.5V from the inner ring and ground for the outer ring but only the on off button is opposite. I'm using the relay to push the button one by one not two at the same time. I can get it as fast as 50ms high and low.

    Can·somebody post the schematic or pic of the setting.
  • William BrownWilliam Brown Posts: 9
    edited 2008-12-25 09:55
    So, it sounds complex what you're doing...

    ....having been a tech for Sprint for about 4 years, it seems it would be easier to just build a serial cable and access the handset through serial functions. All manufactures have them for programming and testing, modem dialing, all sorts of things.

    This seems a bit more functional with a stamp. You could also access the headset port, and use the parallax text to speech to send voice maybe.

    I don't know... just a few ideas from a newbie device hacker.
  • manzanamanzana Posts: 24
    edited 2008-12-25 14:28
    No comprendo William. I understand the serial cable but is this handset something I can buy? Would appreciate more info, thanks. ..· manzana
  • sam_sam_samsam_sam_sam Posts: 2,286
    edited 2008-12-25 14:53
    ·LuXo12

    Could you post a drawing of how you hook up these relays on the output side of these relay
    I know how to hook up the input side of it

    In the data sheets it dose not show a test hook up


    Thank You for any help that you can give with this

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    ··Thanks for any·idea.gif·that you may have and all of your time finding them

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    Sam
  • William BrownWilliam Brown Posts: 9
    edited 2008-12-25 20:52
    Oops, sorry, the handset is just the reference to the phone. Sadly, we've all been trained not to call them "phones" anymore because they do more than just make calls. Sigh, stupid marketing.

    Yeah the serial cable can interface with the phone, and make it dial out. A lot of phones communicate via TTL also. You would just have to look up the manufacturers specs on it to see.
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2008-12-25 21:19
    These links are to the same project, one is a continuation of the other (must not have bookmarked his subject) after some hiatus, for using a Tracfone [noparse][[/noparse]C168i] with the Propeller.· The info regarding the handset's "serial port" is still insightful.
    http://forums.parallax.com/showthread.php?p=744931
    http://forums.parallax.com/showthread.php?p=756456

    Post Edit -- adding...· http://forums.parallax.com/showthread.php?p=761430

    Point being: depending on what you want to do, instead of making some relay_contacts-to-buttons interface, you may get by with a cable.

    Post Edited (PJ Allen) : 12/25/2008 11:03:01 PM GMT
  • azmax100azmax100 Posts: 173
    edited 2008-12-26 06:00
    hi all,

    I've solve the problem. The first·relay is spoilt. After replacing the relay now everything works fine. Now i can control all the function of the cellphone.

    Thanks to all.


    Merry X-mas to all.

    Post Edited (azmax100) : 12/26/2008 6:20:44 AM GMT
  • remmi870remmi870 Posts: 79
    edited 2008-12-26 20:06
    another thing you could consider is using a speed dial so you dont have to dial a number, unless you wanted to be able to send a signal to the BS2 to dial a specific number,(would be nice to use for a security system), and you could save pins on the phone by using a 3x8 converter to use 3 pins to give you 7 differnt buttons, two of these could give you 14 buttons ( you can only use 7 of the 8 bits because a low on all 3 input pins will give you a true on the first pin, so you cant realy use it) but you would only need 6 pins to run the 14.
  • soshimososhimo Posts: 215
    edited 2008-12-29 00:54
    What William described is related to a process called Provisioning, which has many aspects. There is also over the air provisioning which most who have bought a phone from a kiosk is familiar with - they hit a sequence of digits on your phone (usually a bunch of 1's and a # sign) and are presented with a menu to configure the phone with various pieces of information that identify the account and phone that the network is dealing with. Part of this system also allows control of the device for debugging purposes. All of which are very nice, the only problem is that the protocol is proprietary. I only worked at one company (two really, but one became the other) so it may be different for other manufacturers, but I do know for a fact that the software to drive that port was written internally where I worked and distributed to the carriers.
  • William BrownWilliam Brown Posts: 9
    edited 2008-12-29 19:24
    True, but I was speaking more high level than that. Like the commands to use the phone as a modem. Where the connection manager, or terminal software will dial out through the phone, to connect to a dial up internet service provider, or the telecom's internal internet service. Stuff like that...
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