atmel 89c51

Discussion in 'Programmer's Corner' started by gar 88, Mar 8, 2013.

  1. gar 88

    Thread Starter New Member

    Mar 8, 2013
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    hi just wondering if anyone can help me? im doing a security system using an atmel 8051 with 2 reed switches a pir lcd and keypad. does anyone have an outline of a pcb board that would be sutible to use and programming? i would be very grateful if you could help
     
  2. tshuck

    Well-Known Member

    Oct 18, 2012
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    Why not make one yourself? The odds of finding someone that did the exact same thing that you are trying is quite slim. Your time would probably be better spent laying out the board yourself, plus the added satisfaction that you created the whole project.:D
     
  3. gar 88

    Thread Starter New Member

    Mar 8, 2013
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    i dont know how to design one that will do it
     
  4. tshuck

    Well-Known Member

    Oct 18, 2012
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    1.) If you are wiling to learn, you may ask incremental steps to learn what goes into the design of such a project, people here are willing to help. You will be doing most of the work.

    2.) You may get lucky and find someone willing to build/design one for you, more so, you may be really lucky and find someone that will build/design one for you for free. You may be waiting a long while before that person exists.

    3.) You may purchase a ready-made security system, as this will probably offer the actual "security" portion of the system. You might actually be secure.

    If, none of these options are to your liking, please choose another project/hobby/major. I might recommend underwater basket weaving...
     
  5. Brownout

    Well-Known Member

    Jan 10, 2012
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    What do you mean by "outline?" Are you asking for a schematic? You might consider just buying a board. Many are available that will do what you want. You can buy a system with the keypad and LCD already on it, or you can get a more basic board and add those things.

    There are lots of options. I can't recommend any single one without knowing something more about what you want to accomplish and how much of you own work you want to do.
     
    gar 88 likes this.
  6. absf

    Senior Member

    Dec 29, 2010
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    I am currently constructing a PIC controlled burglar alarm using 16F877a. It was from a 2002 magazine by John Becker. Since you're doing similar project but using a different MCU. I would recommend the following road map for your project:

    1. Make the mcu working on a breadboard with a few LED and make them blink first.

    2. Once the basic circuit is working, add in LCD and write the codes for it to display some text on the LCD.

    3. Add a 3x4 or 4x4 keypad to the mcu and write codes for it to detect keys and display them on the LCD.

    4. Add 2 push button switches to the port and write the codes to detect the buttons and storing their states in memory as well as displaying them on the LCD. The 2 switches would be finally be replaced with your reed switches on your alarm system.

    5. Add in the PIR and write codes for it.

    6. Once all the above are working. You can integrate them together and write a flow-chart on how you want the system to work.

    I attached a simple schematic of the mcu connected to a 2x16 LCD and a 3x4 keypad for your reference.

    Allen
     
    Last edited: Mar 10, 2013
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  7. gar 88

    Thread Starter New Member

    Mar 8, 2013
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    thanks that attachment has helped
     
  8. gar 88

    Thread Starter New Member

    Mar 8, 2013
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    yes im looking for the schematic, its for my fyp i have to program the alarm so it can hold a code for activation deactivation and pin change on the alarm, it should also sound the alarm if someone passes by the pir any help would be appricieated
     
  9. ScottWang

    Moderator

    Aug 23, 2012
    4,853
    767
    You need one pin for input detection and one pin for Alarm output.

    I have an idea that you may thinking about it.
    When you calculate all the pins, maybe you can only using AT89C2051 to do the job.

    The circuit as shown by absf on #6, if you change the keypad to 4 output pins and 3 input pins, then the 4 output pins as common lines with 4 input pins of LCD, then it will reduce 4 pins.

    At89C2051 has 15 I/O pins can be used, it will be like this:
    1. 3 Pins for keypad input.
    2. 4 pins for keypad output and LCD data input.
    3. 3 pins for LCD function pin, RS,RW,E.
    4. 1 pin for input detection.
    5. 1 pin for Alarm output.
    It's only used 12 pins, and still has 3 pins left.

    AT89C2051 datasheet.

    If you need more memory for your program, then you can choosing AT89C4051.

    AT89C4051 datasheet.
     
    gar 88 likes this.
  10. gar 88

    Thread Starter New Member

    Mar 8, 2013
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    do you have your pcb board on ultiboard file for that project?
     
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