2008-06-19 17:49:00 by Michael Wheeler in (11 comments) permalink
Long story short, practice tests are boring, and boring times provoke doing boring tasks, such as learning howto decode barcodes.
The coputer read sheet contains a 4 by 8 square matrix, with certain squares blackened.
Hmm, 8 squares, sounds like 8bit binary. Kinda. This is what I learnt, remembering that I was in an exam so I couldn’t use outside world help.
This is the barcode if it was written as binary (the first few attempts of me decoding it failed because I was reading it upside down).
Now to read is quite simple, you get rows B and C and put next to each other, which make a 16 bit binary code.
0000110100010101
Which equals 3349, correct according to the number under the barcode. Now the next problem is what are rows A and D for. I presume they are for check sum, row D is a simple, “this row should equal one” check, but row A is left. If anyknows how the checksum works, comments would be nice. Btw, this was from a QCS prac. exam, I thought they would use something a little more harder.
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/ / / .^ \ Y~Y \.^>/l_ "--'
/ Y .-"( . l__ j_j l_/ /~_.-~ .
Y l / \ ) ~~~." / `/"~ / \.__/l_
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