M-Systems Flash Disk compliance.

Chris Caudle ccaudle at pdq.net
Wed Nov 15 23:03:20 UTC 2000

>Hmmm, I originally thought that the DOC was
>an IDE device;

No, the Disk-On-Chip is just a standard integrated circuit package that you 
connect to a memory bus.  The usual method of connection is to the ISA bus in 
a PC architecture.

>with the wear levelling alogorithm being internal to the
>chip and provided by a BIOS extension.

Correct.  The problem comes because you have to make real mode calls to use 
the BIOS extension.  RTEMS runs in protected mode, so to use the BIOS 
extension, you would have to switch back to real mode, make the call, then 
switch back to protected mode.  Could get ugly.

If you aren't going to use the BIOS extension that gets loaded at boot, that 
is when you need the TrueFFS filesystem code. I think that is called the 
"OSAK," the Operating System Adaptation Kit.  That is provided by M-Systems 
under license.

-- Chris Caudle

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