I have a large number of computers arriving for our computer refurbishing project (

http://helpingtulsa.org) and I need to generate a sequential series of numbers, each with a check digit, which I can print out on Avery Labels (#5160 30 labels to a sheet), so I can stick a label on each computer, and then when it is processed manually type in the number on the label and have the check digit make sure I did not transpose digits when typing in the number.

(1) How can I generate let us say 20 sheets at a time (600 lables), such that the 600 numbers are all unique and include a check digit, and the next time I generate another 20 sheets they use different numbers

and

(2) When I am manually updating the database how can I put validation in an Access Form to perform the checkdigit calculation on the entered number.

I realize many checkdigit routines are based on bar coding, and I don't object if the label includes a bar code version of the number as well as a human readable version, but right now I don't have a bar code wand available everytime I might want to read a number, so the label must have a human readable number, whether it has a bar code readable one or not.

With this autonumber you can use a "modulo 11" routine to generate a checkdigit for printing on your labels.

The modulo is calculated by multiplying the digits with different values and calculating the remainder.

This text from the web shows how:

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In this example, we want to encode the data "21435" in a Code 11 barcode with a single check digit. The check digit is a modulo 11 checksum.

First, we determine the weights of the numbers in the Code 11 barcode starting from the right side of the number. We then multiply the number of the barcode by the weighting and add these together as in the example:

Barcode to encode: 2 1 4 3 5

Weighting: 5 4 3 2 1

Totals: 10 4 12 6 5 Then add them 10+4+12+6+5=37

Next we divide the total by 11 and get the remainder which is 37/11=3 remainder 4. The remainder is the check character.

To type or print a Code 11 barcode encoding the data 21435 that can be scanned, we need to print (214354) .

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This is used on barcodes, but also for your banking number.

Need more info ?

Nic;o)