Posted by jim guerber on December 17, 2003 at 08:10:32:
In Reply to: Consistant Error 87's. posted by Herb Walters on December 17, 2003 at 06:46:34:
So, The Errors started BEFORE you tried to upgrade them? Did you change ANYTHING before the error 87's started?
Here is what is happening:
Comet is trying to read a file. Using DOS calls, it LSEEKS to the place it wants to read some data and issued a DOS read for the amount of data it needs. Comet then checks the amount of data that DOS returned. If this does not match the length it wants, it retries the operation some number of times(I don't remember how many).
If the number of bytes read still does not match what is expected, Comet will issue an error 87.
If indeed nothing was changed in the software and the errors started to happen, I would expect something went wrong in the hardware, or cabling.
There have been many minor bug fixes between Comet 504 and Comet 2004 which would make the connection between the user program and the data more robust. Even so, I don't know whether changing comet versions can get around the kind of problem you describe.