Bar-code Scanners for Linux?

peterjm asks: "Well, some one here at work has decided that the answer to all of our problems would be the acquisition of a bar-coder/scanner for labling and keeping track of all of our pc's in the office. A web hunt reveiled all sorts of the little suckers, but what I was wondering is, are there any bar-scanners that are designed (or have software designed) to run under Liunx?" Linux needs support for some of these if it wants to be considered as a possible tool in the retail market.

Shouldn't be a problem

[jellicle]

Scanners come in several flavors. What you want are decoded, keyboard-wedge scanners. These interpose themselves between the keyboard and the keyboard port, and when they scan something, they insert the characters just as if they had been typed on the keyboard. The system shouldn't be able to tell the difference between characters produced by scanning and characters produced by typing, so there's no question of OS-related problems.

Other scanners connect to the serial port and require specialized software to take the input from that port and insert it into your application. You'll want to avoid these in most cases - especially if such software doesn't exist for Linux. :)

Oh, and one more thing: Symbol [symbol.com] is the largest producer of scanners in the world, and according to an engineer friend of mine who works there, they put a lot more into quality-control than other companies. Their scanners are often available at discounts of 50% or more off list price (because list price is horribly inflated), so shop around for your reseller and find a good price, but buy a Symbol scanner in the end.

--
Michael Sims

Re:Shouldn't be a problem

[Anonymous Coward]

Keyboard connection
I'd like to second the recommendation for a scanner that goes between the keyboard and the computer. They are fool-proof to get working. The one gotcha is that some of the units are powered from the keyboard connection. I've fried several new ATX motherboards, because the scanners use too much power. If the scanner has a walwart or you use older machines (with standard keyboard connectors), then you should be fine.

Serial connection
This is what I suggest. Because the scanner input isn't "inline" with the keyboard input, you can differentiate them. For example, if you look at many POS systems, you'll see that the operator has to tab (or some other key) over to the appropriate box to enter the SKU or UPC code. With the scanner connected serially, you automatically know this input is a barcode. This doesn't seem like much, but if you have employees scanning things hundreds of times per day, then the time saved and errors reduced add-up. All of the serial scanners I've looked at used a simple, well-documented protocol, so I'll disagree with the previous posters suggestion to avoid them with Linux.

Whatever you decide, don't decode the barcode yourself. I design terminals for machine monitoring systems, and I've spent the last 17 years tweaking the software on a system that connects the reader diode to an input on a processor. The reader costs us about $8 versus over $100 for the board from Symbol to do the same, so we're stuck doing it by hand. The problem is that Symbol's readers are so much better than ours, it's embarassing. For a test-set of cards we bought long ago (some are intentionaly impossible to read and it counts against you if you return a value and many have exagerations of problems commonly found on printed cards like low contrast, skews, missing dots like you have with a cheap plastic ribbon, etc.), the Symbol unit can read over 90% of them versus our 70%. So, bite the bullet and by the much more expensive reader.

future project

[jfernie]

One of my back-burner projects at work is to get some magnetic buttons from www.deggy.com to work under linux. I've seen some MSAccess code which talks to their reader through serial interface. Shouldn't be that hard to do the same under linux, just need to find the time...