scanning barcode

[chuckgoss]

Hi all...I don't know if this is a weak spot in access 97 or not, but here we go.

I am finally and successfully able to print a barcode lable (code 3 of 9 non-extended)for each part that gets returned back into inventory from my form, thanks to some freeware written by a fellow named James Mercanti. It works by drawing the barcodes as rectangular boxes...very slick stuff.

The question is: When I scan the bar, occationally the first scan will reveal only part of the number that is encoded. All subsequent scans of that number or any other number seem to work fine...the problem is on the first one. If I scan (for testing purposes) into Note Pad or something, I have much better success of a good scan than if I scan into Access 97. Access has a much higher failure rate than any other kind of program that can translate the bar into alphanumeric characters.
Has anyone else experienced this kind of weakness or can anyone give me any ideas about how to resolve this?

thanks in advance

chuck

 

[pcs]

i assume you are using a kb wedge...

when you say:
occationally the first scan will reveal only part of the number

is it consistent...ie, does it always drop n characters from the scan?

al

 

[chuckgoss]

Al...
Thanks for the reply. I have to plead ignorant when it comes to what a KB Wedge is. In response to your question regarding inconsistent scaning: It is not the same characters or same number of characters that fail to be read. For example: I have a test part number of 3333-3333. Sometimes it may scan: 33-33, or sometimes 333-33. Alpha characters also result with the same inconsistent behavior. In other words, it does not favor one group of characters and dislike others. I use a hand held scanner that I shoot at the bar from a distance of about 5 inches.

thanks for your ideas on this...

chuck

 

[AlanS]

"KB wedge" means a keyboard wedge, which is a device connected between your computer and your keyboard, so that the bar coded data appears to the computer as if it had been typed at the keyboard. The other common way of getting the bar coded data into the machine is via the serial port.

If you're using a keyboard wedge, you have to be sure that the desired application is ready to receive what is effectively typed input - it must have the focus, the insertion point must be in the correct field or other location, the system must not be busy processing other tasks which would interfere with capturing and processing keystrokes, etc. Off the top of my head, I think a likely cause of your problem is that the application is not immediately ready to receive the scanned data, and/or it is seeing the initial characters of your first scan as positioning or other control instructions, rather than as data.

You might also want to talk to Mr. Mercanti to be sure you are using his software as intended.

If your scanner can produce serial output, you may also want to switch to a product like Software Wedge, which acts as a communication bridge between any serial device (not just scanners) and any application (both DOS and Windows versions are available). I used to work for the company that sells it (TAL Technologies) and found it to be a good product. You can get more information about it, and lots of tutorial and reference information about bar coding, at their web site: http://www.taltech.com.

As an aside, be sure the bar codes are being printed correctly and accurately - my guess would be that they are, since your scans after the first one seem to be reliable. But keep in mind that the technical details of how the bar code is generated, represented (in memory or in a file) and printed can all have an impact on the accuracy of the image, and whether it will scan correctly.

Hope this helps.

 

[pcs]

edit:
or what AlanS said

chuck,

a wedge is a method of connecting the scanner between the keyboard and the computer. the scanned characters then appear to the application as having originated on the kbd. i haven't worked with scanners in a while, but most have a means of setting how fast the scanner jams the characters into the kbd buffer. i suspect your scanner is sending data faster than the buffer will will handshake and accept it.

i suggest you consult the documentation for you scanner and experiment with the settings.

hth,
al




[This message has been edited by pcs (edited 12-11-2001).]

 

[chuckgoss]

Thanks all...great grist for thought! I am using the wedge as described, and it is very possible that the receiving program is still "comming up" or doing some other processing at the time of the scan. As for the speed of transfer, I will look into that. The PC is a rather old and down level one.

As for the author of the code, I have been unable to reach him for comment. The code was posted about 5 years ago, and the links that it contains to get back to him are all expired at this time. I had had a problem with a small detail it contained (totally unrelated to this problem), and ended up solving it without his help after much struggle.

thanks again for your great input...

chuck

 

[DJ7T]

If you've put a lot of work in this, you might be angry to know that there are a smattering of Barcode TrueType Fonts if you look on the net a little. Then you can have Access return the SKU number and print it in the barcode font and it'll make a legal barcode every time.

Hope this helps a little...

-Mark

 

[pcs]

a couple of final thoughts...

to verify that your 3of9 codes are viable...decrease the scan distance from 5 inches to something lesser, if the 1st read accuracy improves, you may have faulty printing of your barcodes. (i doubt this is the case, however)

you wrote:
--------------------------
The PC is a rather old and down level one.
--------------------------
don't waste your time going down this road, the oldest PC around is fast enough to capture barcode inputs, as long as everything is in sync.

hth,
al