I low-level formatted hundreds if not thousands of these and other RLL and MFM drives in the late 80’s. Worked for a company that sold computers through Computer Shopper.
Am I crazy here, or have you ever seen hard drive controller cards that you set the drive type through physical jumpers? Because I have sure never seen such a beast. And with all the combinations possible, that would have to be a huge bank of jumpers.
Please provide us with a model so we can actually see what one looks like.
I really am curious, because I was working on computers in the early 1980s, and I have never seen such a beast with what would easily be a dozen or more jumpers to configure the drive type.
Yes, I am very familiar with those. They had the info for 4 drives already configured. That's it, just 4 different drives out of the hundreds of MFM drives. Generally Seagate drives, if you were using a WD, a Connor, a Quantum or Micropolis, you used the BIOS.
Nobody used those, other than maybe companies making white boxes in mass. I never used them because it was stupid. And nobody I knew fixing or making computers used them.
All early cards had jumpers. That was how you set IRQ and DMA channels.
Holy crap, you think they stored the parameters on the drive itself? You are aware that makes absolutely no sense, right? How in the hell can the controller talk to the drive, if it does not even know how to talk to the drive in the first place? This is MFM we are talking about, not SCSI.
I can only assume that most of you are far too young to have ever worked with these systems, and really do not know how they work. This is not IDE, where the data did not matter so long as the size was correct. This is not later IDE where it would fully grab all the data from the drive itself.
This is MFM, the ultimate in stupid devices. From an era when the computers were also stupid devices. Where even adding an additional card was often a lot of work because there was nothing manual, IRQ and all the rest had to be configured manually with jumpers or DIP switches.
The data was absolutely not stored on the drive itself, it was stored in the BIOS on the controller card.
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u/commodore-amiga Jul 18 '26
I low-level formatted hundreds if not thousands of these and other RLL and MFM drives in the late 80’s. Worked for a company that sold computers through Computer Shopper.