Bill Studenmund wrote:

>On Fri, 11 Aug 2000, Bob Nestor wrote:
>
>> If you're talking about the same field I think you are there are some 
>> additional values that Apple is also using.  0x701, 0xffff, and 0xf8ff.  
>> The original value of 0x0001 meant to try to load/boot from a non-chained 
>> SCSI driver; the complement (0xffff) is reserved for the chained variant 
>> of the driver.  The 0x701 is the non-chained driver for the IDE, and the 
>> 0xf8ff is the chained variant of the IDE driver.  This is documented, 
>> although not very well, in some of the new Tech Notes.
>
>For clarity, I'm talking about the ddType field in the Block0
>structure. It's on page 3-23 of my copy of Inside Mac: devices, and on
>page 557 of IM:V. Interestingly enough, they both say that you can use the
>Start Manager's SetOSDefault value to choose which one gets loaded...
>
>The real question is if OF cares about these values. :-) For macppc, I
>don't think we'll ever need to use the Start Manager to get booted.

Apple has recently redefined or extended the definition of a lot of the 
fields in the Partition Map, including this part of Block0.  If you 
haven't already looked at their Technote #1189, "The Monster Disk Driver 
Technote", you should.  The booting process has changed a bit to support 
mulitple systems and disk configurations.

-bob