CRC question

[dwight elvey]

> From: cclist at sydex.com
---snip---> > Could even be XORing the contents with a LFSR. Hard to say without > seeing it. > 
Hi
 Of course, a CRC is just a special polynomial LFSR that has
a large field of zeros so that it cna be used for burst correction.
 It seems the code is CRC. The code may just do a bit at a time
or may have a table lookup to do a byte at a time. I've even seen
nibble at a time.
 If it were doing a real CRC, one could even locate a burst
of bit errors and fix the EPROM if one knew the polynomial
used.
 To my knowledge, I don't know if any of the assemblers had
a CRC calculator built in. The final check number was most
likely calculated after the assembly and just added to the code.
If in the listing, this may have been a second pass through
the assembler.
Dwight
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