VaX#n8 <vax@linkdead.paranoia.com> writes:

> 
> (like, hmm, the 64MB limit [...]

I'm already working on that.  There are 5 alternate methods I know of
for probing the memory size (pulled from Ralf Brown's interrupt list).
Unfortunately, 2 of them cause some machines to do weird things.
Sigh.

> In the mean time, I'm wondering about some of this stuff.
> 1.  why care about 0:0x7c00 vs 0x7c0:0  -- aesthetics?

The code is linked at address 0.  You could link it at 7c00 instead,
but that would screw you when you hit stage2.

> 2.  why reset the floppy system with int 13h service 0, and NOT reset
>     if loading from hard disk?

It's conceivable that some `disk manager'-like program has installed a
different geometry for the hard disk, and resetting it would cause the
boot block to malfunction.

> 3.  why override the drive number to zero if booting from floppy? (!)

Because that's what Microsoft does?  Many BIOSes don't reliable report
the drive number to the boot block.