All things ESDI

[Dennis Boone]

 > ESDI was common in high-performance machines and for "large" drives
 > - 120MB was about the smallest I saw (when 20MB - 40MB was still
 > common) and ~330MB was typical. I have heard of ~600MB units but
 > never installed one.

I think I handled a 600 in a Novell server once.

 > It's an Int11 device, just like an ST-506 drive. The BIOS needs
 > to be configured with the right number of heads, cylinders and
 > sectors-per-track, tho' picking type 20 or so will usually give you
 > enough to boot and read the true settings off the drive itself. They
 > will probably need to be low-level formatted if moving them from
 > one controller to another. DEBUG and then G=c800:5 is what I dimly
 > recall for this, tho' in later years I used CheckIt or even SpinRite
 > to do this.

I'm inclined to disagree, though I'm hardly the expert.

Specifically, I recall having trouble setting up several ESDI drives
in servers.  The fix was to tell the machine BIOS the disk didn't
exist, then let the ESDI controller BIOS work out geometry.

I think on some ESDI controllers, the C800:5 trick did work, though.
That was a common disk interface, MFM, ESDI etc.

De