# Barcode Scanner (Line Reader) Circuit Diagram

Discussion in 'Homework Help' started by elinque, Aug 17, 2008.

1. ### elinque Thread Starter New Member

Jul 9, 2008
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anyone has this circuit diagram?? i need it for school project yet couldn't find..

2. ### kammenos Active Member

Aug 3, 2008
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?????
What diagrmam? The whole scanner? Where do you go to school? What kind of school wants a barcode scanner circuit for project 8|

Apr 20, 2004
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4. ### elinque Thread Starter New Member

Jul 9, 2008
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Can the CCD method works far range??? if so, can anyone provides me with a circuit diagram of the barcode scanner circuit diagram?

5. ### CVMichael Senior Member

Aug 3, 2007
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At my previous job I had to use barcode scanners. I used CCD and also laser scanner.

CCD is for short range, 1-2 inch, and it's limited to the size of the barcode also, i.e. if the barcode is printed on a full page (very big), there is no way you can scan it with a CCD scanner. Laser is much farther, I think I scanned from as far as 2 feet, and the size of the barcode it does not matter that much, if it's big, you just scan from further away then normal.
I think laser is faster too... with CCD you have to move it around to get the right position until it scans, but with laser, you just point anywhere on the barcode, and it scans right away...

I always hated to use CCD scanners becuase of it's limitations.

But if you DO find a circuit diagram for a CCD scanner, I would be very interested to see it because I want to use CCD for something else, and I have no idea how to read the information from the CCD array.

Apr 5, 2008
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7. ### elinque Thread Starter New Member

Jul 9, 2008
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can anyone provides me a with CCD and laser scanner circuit???? thanks a lot.. i need it very much..

8. ### CVMichael Senior Member

Aug 3, 2007
416
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Well, if you can figure out how to read the data from the CCD array into a microcontroller, then the rest is easy... then it's just a matter of programming the microcontroller, and that is easy for me (since I am a programmer).

(to continue my sentance)
.... and I could write the code for you to read the barcode if you don't know how.

By the way... what barcodes do you plan to read ? Code 2 of 5, Code128, Code39, etc. ? (I only have experience in Code128)

Last edited: Aug 19, 2008
9. ### elinque Thread Starter New Member

Jul 9, 2008
9
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i'm just planning to do a simple project for the school. the barcode would be scanned. example, bus 31. meaning code 31?? is that right?

yeah, i do need help in programming. i'm planning to do a barcode scanner. and a barcode . when the barcode scanner scan the barcode, it would send a signal for it to sound out the number , "Bus 31"

10. ### kammenos Active Member

Aug 3, 2008
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It is not only a circuit. Is a whole project with circuit AND programming. It will not be so easy

11. ### elinque Thread Starter New Member

Jul 9, 2008
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ya, i'll be going down to some electronics store tmr to get the components hopefully can find. so i'll first do up the circuit of the barcode scanner..

12. ### CVMichael Senior Member

Aug 3, 2007
416
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There is no such thing as barcode "Bus 31"... I think you should review your requirements, and be sure of what you need to do...

If you want to generate a barcode, then I have code here that will generate barcodes using Code 128:

13. ### elinque Thread Starter New Member

Jul 9, 2008
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what i mean was... i'll generate the barcode using ur Code128. As, i'm using only numbers like 31, I'll require the Code128 to generate barcode 31.

and once it reads the 31, i need it to let it produce a sound, like "Bus 31"

meaning , i'll do a barcode scanner circuit, the scanner scans and reads the barcode, then sends a signal to activate the sound "bUs 31"

is it very hard??? i'm afraid i cant get it done..

14. ### CVMichael Senior Member

Aug 3, 2007
416
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You mean you want it to Speak what it reads ?

Do you want the hardware to do that ? I mean the barcode scanner ? or you want the computer to do speak (if the scanner is connected to the computer that is....) ?

If you want the computer to say what you scanned, then you need a text to spech control, and I think that it comes with MS Office, otherwise I'm sure there are text to speech controls that you can download off the internet. Then you have to make a program (in whatever programming language you know) that gives the signal from the scanner to the speech control. I played with text to speech a while ago using VB6, it was fun...

If you want the actual scanner to say what it reads, then there are chips that you can get, for example this one:
http://www.robotshop.ca/home/produc.../audio-synthesis/magnevation-speakjet-ic.html
And I'm sure there are many others, do a search...

15. ### elinque Thread Starter New Member

Jul 9, 2008
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hmmm. i think we'll be using the 6811 microcontroller to test out the circuit. there shld be a speaker on it i guess..... i want the speaker on the mct to speak out what it reads.

16. ### beenthere Retired Moderator

Apr 20, 2004
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Perhaps you should spend some time reading data sheets. The 6811 (more properly 68HC11) does get used with barcode readers - http://en.wikipedia.org/wiki/Freescale_68HC11 - but has no ability to produce sound.

For any uC to make sound, it will need a digital to analog converter feeding an amplifier that drives the speaker. Speech produces a complex waveform, so having speech samples on tap in memory for a MIDI-type playback might just be feasible. If, of course, you have the means to digitize the speech samples.

You will learn a lot by just handling the scanner input and translating it to a display. It may seem very simple now, but you are going to have to learn quite a few skills in order to complete the project. Or have you written programs before?

17. ### elinque Thread Starter New Member

Jul 9, 2008
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hmmm, i only have done a very very very simple program. in that case, maybe i'll just need to read the barcode and output it to turn the LED lights on . ...

18. ### CVMichael Senior Member

Aug 3, 2007
416
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If the 6811 microcontroller does not have a built in speech synthesizer, then I really doubt you can make it speak because it is very difficult to do it through software. Unless you get the softare that already does it from somewhere.

Just because it has a speaker it does not mean you can get it to speak.

As I sugested before, just get a chip that does it, and you just send signal on what to speak.

And if you still don't want to do that, then the next best option is to have everything pre-recorded, and just play the wave file corresponding to what you want it to say, but for that you need a storage device large enough to hold all the sounds...

Remember the KISS principle, especially that you are a beginner, just get chips that already do what you want, don't reinvent the wheel.

As for reading the barcode, I am interested in that also. The only problem for me is that I don't know how to read the CCD array, I can do everything else...

19. ### elinque Thread Starter New Member

Jul 9, 2008
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hmmm... i really dont know how now..

Dec 15, 2008
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