On Thu, Aug 23, 2018 at 12:43 PM, Tom Gardner via cctalk < cctalk@classiccmp.org> wrote:
> Well it all depends upon what u mean by "first" > > The Sony drive and cartridge were not compatible in many ways with what > became the physical, magnetic and electrical interface standards for the > 3.5-inch drive and cartridge. The standards came out of the "Microfloppy > Industry Committee" (Google it with quotes) organized by Shugart Corp. > Either Shugart or Tandon was the first to ship drives compatible to the > standard. Tandon probably did the first such cartridge. > > The original Sony drive and cartridge died out and Sony didn't come out > with > a compatible set until well after Shugart and Tandon. The early adopters > of > the Sony design like HP then changed to the industry standard design. > AFAICT, the only difference was that the pre-standard Sony 3.5-inch diskettes had a manually operated shutter. The manual shutter and automatic shutter 3.5-inch diskettes are interchangeable with some care. For a while, diskettes were sold that had the automatic shutter, but also had a way the user could latch the shutter open, so that they could be used in early drives that didn't have the pin to open the automatic shutter. I only ever saw the manual-shutter drives in Sony and HP equipment, though I wouldn't be surprised if there were some other uses.