limiting hard drive size--wrap-up
Just a reminder, the application that this HDD is going into is NOT a typical PC motherboard. It is going into a piece of hardware that may not even be x86 based.
I have no access to the 'bios' nor would I want to mess with it.
I have two HDD with the identical Toshiba model numbering. The reduced sized drive came from the vendor of the embedded controller.
Anyway, I'm still pretty much convinced the HDD controller 'bios' has been modified to present itself as a 10gb drive. I haven't come across any information about accessing the drive in any manner other than the normal data read, data write and bios handshaking by the mb at initialization. I did find a interface specification describing the various data formats most of which seems to have nothing to do with the normal ATA data read/write. I've swapped these two 'identical' drives back and forth on a couple of my PCs and they consistently show the normal 20gb and reduced size (10gb) sizes, respectively.
Looks like we are going to have to suck it up and put out the $500-$600 the vendor wants for a replacement 10gb HDD. (Notice there are no longer available 10gb Toshiba 2.5" drives, thus the 'reprogrammed' 20gb drive model.)