Installing PC-DOS 7 was quite difficult. I discovered that the floppy drive was unable to detect floppy ejection. PC-DOS tried really hard to recover from error with a double "Abort, Retry, Fail" which triggered the OS to read again the floppy directory. But most other software failed to install.
I had read a bit about how the PS/1 used custom drive connectors which also included the power supply[1]. But when I removed the drive I found something standard with ribbon cable for data and a Berg connector on the left for power.
The drive looks like the part that shipped originally. It even features an IBM part number (P/N) 1619655. I searched the internet for the same drive but was unable to find one. I ended up picking a SONY MPF920-1 and immediately ran into problems.
Can you spot the difference in the back of the IBM and the SONY drive?
There is a notch which forces the ribbon into being "up" or "down". This is to avoid connecting the floppy drive ribbon in the wrong orientation.
On the Sony that meant the red wire would face the right side. That is contrary to the custom of having the red wire towards the power connector[2]. The IBM notch forced the ribbon in the other direction. Would it work?
I tried and the floppy drive LED stayed on all the time, which was a sign it was plugged in the opposite of what it should have been. I carved the plastic to add a notch allowing to reverse the ribbon but the floppy still did not work.
To this day, I don't know what model of PC this floppy drive was built for. Perhaps a Japanese PC-98 or FM Towers?
I went back to eBay to find another Floppy Disk drive. It is worrisome how rare and expensive beige FDD have become. Not surprising considering we are dealing with 30 years old piece of technology.
The third time was a charm. I now had a functional floppy drive.
| ^ | [1] | How to replace the custom floppy drive with a standard one |
| ^ | [2] | IBM PS/1 2168 restoration: Floppy drive replacement struggle |
