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Checksum Algorithm

Targhan * 24 Jun 2021 00:29:17

I see a new article by Grim! Thanks!

Just a few questions:
- Only the first listing is credited. Are all the others from the same author, or from Grim?
- I know it should be easy to find, but maybe a few links about HOW to calculate the hashes? I'm pretty sure there are thousands of CLI tools that do that, but one link would be enough.
- Is there a "collision" rate that could be put in the table with each algorithm? One would be tempted to use the fastest!
- Maybe a small conclusion, for beginners, about how to get a CRC from a file, and compare the result? How is encoded the 32 bits result (is HL the Most Significant Word?)?

One again a very interesting article. But like often, without a full context, a lot of people will be bummed by it and miss an opportunity to learn something that could be useful.

Targhan * 24 Jun 2021 09:28:35 * Modified at 09:28:50

Ah, an interesting addition would be about how to create such CRC in Z80 (maybe not all, but at least one).
For example, in Orion Prime, I did a little checksum check in the save games to be sure no one tampered with its bytes for cheating (actually, it was only a special encoding using a seed written in the first bytes as a decoder, but the goal was the same).
So a CRC, even simple, to make sure data generated on a CPC are not modified, would be useful.