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Re: Memory Card Corruption Problems



"Ian S. Piper" wrote:
I still need answers to my questions below.  I was hoping Tab or Guy might
be able to answer them.
  Okay, I'll try.
> How is 1.95e different from 1.94w?  Is 1.95 code based on 1.94 structure?
> Or is 1.95 a complete re-write?
  1.95 is branch off of 1.94s and the branch has been, as much as has been possible, kept in sync with the 1.94w code updates.  So 1.95e is minimally different than 1.94w.  Check the release notes and you'll see that the changes are largely in counting logic.
> Does it perform less multi-threading, and therefore have less data
> traffic?
  No.  There have been no changes to the underlying operations.  Thus I have trouble accepting that 1.95e doesn't suffer the same memory card corruption problems as 1.94w.

  And for a little more perspective, we first added complete checksum and consistency checks to the memory cards with release 1.41 in November of 1989.  This helped us trace down some programming errors that were causing corruptions and also helped us detect corruptions sooner that were caused by motor control and other timing functions.  But we have never had a release that didn't occasionally get unexplained memory card corruptions.  Not that we haven't chased a lot of theories that proved groundless.  The problem is that we have not been able to set up tests that would reliably reproduce the corruptions.  It could be that we could avoid the problem with some timing adjustments but what timing adjustments.  I'm hoping that the EE study could help us there.

         Guy