HP 35s Checksum explained

[MarkHaysHarris777]

(02-09-2015 04:37 PM)Didier Lachieze Wrote:  Anyway the point here, as was established soon after the launch of the 35s, is that the checksum values on the 35s are not reliable as they depend on the calculator context and not only on the program for which the checksum is provided.

I don't believe it was established, not in a deterministic way. Also, there is a difference between 'reliable' within context, and 'reliable' for context. If two different machines produce two different checksums (and I cannot reproduce that on my machines so far) then the checksum might NOT be reliable for contextual checking (between machines), but might be absolutely reliable within the context of the machine itself.