CMI 6426 hard drive misunderstanding parameters

[romanon]

Hello,

I wonder why the disk CMI 6426 is labeled as type 2 in the IBM disk table. Type 2 is defined as 615/4/17 as we know. CMI 6426 has 640 cylinders according to several sources.
Was it an attempt to fit into predefined IBM tables?

R.

 

[bburley]

This is data from a program called Diskbase


Reduce Write being higher than the number of cylinders would just mean that it doesn't apply. Is that (or the Landing Zone) what other sources looked at?

 

[romanon]

Wellll, this is from Statson


and this from CMI Advertisement for their disks

 

[bburley]

Perhaps it was standard practice to use the more commonly available settings and Diskbase was in error. It does seem to make sense that to use a common setting would make for easier interchangeability with systems that didn't have a custom drive option. Have you tried formatting with 640 cylinders?

 

[romanon]

Not yet, I've only worked with these disks on IBM AT systems so far.