Friday, July 27, 2012

Seven Segment Up Counter and Timer Circuit - 16F628

PIC16F628 Counter Circuit
Circuit diagram

The project shows what can be done with a micro and you can modify it to set an alarm at any count-value or set a limit such as 'count-to-60'. You can add a buzzer or relay or increase the display to 3 digits. You need to remember that each additional display will reduce the illumination of each digit as they are 'multiplexed (time-sharing)'. Full circuit diagram including programming socket.

The displays do not affect the 'In Circuit Programming' as they are not active when programming and do not load the outputs. Any 7-Segment displays will work in this circuit. You need to identify the pin-out of any display you use. (Common Anode displays can be used providing you invert the values in the display table. A PNP transistor will need to be used.)

Testing the circuit

Check the circuit by removing the chip and taking pins 6 and 18 to the 5v rail ad make sure segment 'A' illuminates. Do the same for all the other segments.The circuit diagram does not have any voltages marked on it as the circuit is DIGITAL.All the 'lines' or 'wires' or pins of a micro-controller will have rail voltage (5v) on them when they are HIGH and when you come to a resistor, the resistor will drop a certain voltage. The voltage it will drop will be the difference between rail voltage and the voltage developed across the component it is driving. If it is driving a LED, the LED will drop a characteristic voltage of between 1.7v and 3.6v, depending on the color. If the component is a transistor, the voltage developed between the base and emitter will be about 0.7v.

Use Micro C For Compile.

MikroC

PIC16F628A Datasheet

PIC16F628A Pin
pin-out



PIC16F84A Datasheet

PIC16F84A Pin
pin-out


12 comments:

  1. friends
      It works the same with 16f628

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  2. Does not work none of the 2 time does but the coding of the display codes is any you do not see numbers just extraterrestrial counts

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    Replies
    1. It is working. Simulate Proteus file. you can see it.

      Delete
  3. Which version of Proteus are you using. Is it Proteus 7 or Proteus 8

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    Replies
    1. I think Proteus 7, because this is old project

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    2. I'm looking for up and down counter using three 7-segment, instead of two. Something that can count up to 900. I need your help.

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    3. https://scopionz.blogspot.com/2014/04/4-digit-ssd-up-counter-pic16f628a.html

      Delete
  4. there is no .hex file inside the zip file. please provide the .hex file, or how to convert them to hex file????

    ReplyDelete
    Replies
    1. http://www.mediafire.com/file/54us3ml70lsmoh6/counter.zip/file

      http://www.mediafire.com/file/28f86074dika88s/Timer_%2526_Counter.zip/file

      http://www.mediafire.com/?dszhgbzkd42z7oj

      Delete
  5. Design a system having four users and a host Host will ask a question and a timer f 15 sec will get start. All the users will have a buzzer button to reply to that question. The moment any first user reply, counter will stop, and no other user can reply. A 7-segment display will show the i user number and a green led will gets on. If counter overflows and users failed to reply in the allocated duration, a red light will glow with a buzzer,

    ReplyDelete