take a look at the "2 of 5 interleved" format it would be a very small code.
michael

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>
>        2. - To put a bar code on them. This has many possibilities, but
bar code
>scanners
>need a minimum size for the code which is very large for the available
>space. Because of this, I was thinking of inventing my own code, since it
>only needs 90 combinations.
>
>