PRB: Writeback Cache on SH3 May Cause Corrupted Data
Article ID: 199541
Article Last Modified on 12/5/2003
APPLIES TO
- Microsoft Windows CE Embedded Toolkit for Visual C++ 5.0, when used with:
- the hardware: SH3 processor-DO NOT USE!
This article was previously published under Q199541
SYMPTOMS
With the writeback cache enabled on a SH3 based system, a 16-byte run of zeros aligned at a 16-byte memory address, may appear in place of the expected data.
CAUSE
The cause of this problem is not yet known. Neither Microsoft nor Hitachi have been able to conclusively locate the cause.
RESOLUTION
The SH3 implementation of the Windows CE operating system provides a configuration setting that allows an OEM developer to control the cache enable bits of
the processor. This setting, OEMExtraCCR, should be set in the OEMInit() code in the OEM's Adaptation Layer (OAL).
At this time, it is recommended that the writeback cache be disabled (the cache should be placed in write-through mode)
STATUS
Microsoft is researching this problem and will post more information in this article when the information becomes available.
Additional query words: kbDSupport
Keywords: kbprb KB199541