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<== Date ==> | <== Thread ==> |
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Subject: | Re: VME Bus Error handling on MVME3100 and 6100 boards |
From: | Andrew Johnson <[email protected]> |
To: | Till Straumann <[email protected]> |
Cc: | EPICS tech-talk <[email protected]> |
Date: | Thu, 10 Aug 2006 14:58:19 -0500 |
This behaviour is not possible with the Tempe chip - VME read cycles that terminate with a Bus Error just return 0xFFFF values (all one bits), and by default there is no indication that anything unusual happened. It is possible to enable the VME Exception interrupt, which will eventually be serviced by the processor and most of the time would allow the BSP to suspend the correct task (assuming that the Bus Error wasn't caused by an Interrupt Service Routine), but that interrupt could be delayed for quite a long time by other pending interrupts.
So why would you care? The faulting task would still not be able to make any progress and hence be suspended right at the faulting instruction.
- Andrew -- Not everything that can be counted counts, and not everything that counts can be counted. -- Albert Einstein