ST351 A/X in a Commodore Colt

[KenEG]

I tried to install this drive in my Colt tonight. The "Hard drive not found" message went away, but fdisk sees a non-DOS partition that it won't delete. The drive was jumpered in AT mode when I received it. I have tried it jumpered as 40, 30, and 20 MB. They all show yep the non-DOS partition. I have jumpers 1-2, 3-4, 7-8, and 11-12 set at present. Using g f000:5 in debug locks up,the computer. The drive has a sticker on it that says not to low level format it anyway. I just thought I might get a clue from whatever that utility would show me. Note: I have the 12 pin with both power connectors version of the drive.

 

[KenEG]

OK, I misremembered the command. I looked at the wiki and used G=FA00:5. It seemed like the computer locked up, but when I rebooted and ran fdisk, the non-DOS partition was gone! Set to 40MB mode, it shows up as a 10 MB drive. Not surprised, but was hoping my BIOS was new enough to see the full 40 MB. Set jumpers to 20 MB mode and ran fdisk again. Now I have a full 20 MB. That is OK since that my original Colt had a 20 MB drive. My guess it that the drive had been used in AT mode and that is what fdisk saw as a non-DOS partition.

 

[SpidersWeb]

You can use ANYDRIVE or similar tool to change the drive geometry before DOS boots. Little program that sits in the boot sector.

I've ignored my sticker before, but did follow instructions from someone who had done it before exactly to make sure I didn't brick it.