school) so they could have different hardware, but reality was different and users became quite demanding to upgrade while using DOS. From an Apple management point of view they were different markets (home vs. A very common hack was to solder the second PROM onto the first and select each with a manual switch. This created a situation that Pascal could use the same disk as DOS with about 20% more space and even worse, people using Pascal and DOS had to swap PROMs (or own two controllers). The Apple II emulation included a 13 sector RWTS, to be loaded before accessing any Apple II disks.

The 16 sector format was reserved for the Apple III (and Pascal). Thus disk controllers were still shipped with 13 sector PROMs and DOS 3.2 only supported 13 sector format. Management believed that it should be superior in every way and no II model should have similar capabilities. It was usually also bundled with a language card (16 KiB memory card).Īt that time Apple was all about getting the Apple III to market.

The Pascal System went on sale as a set of disks and a PROM to be placed on the Disk II controller card. Wozniak developed the 16 sector format in 1979 for the Apple Pascal System, as otherwise the UCSD P-System would not only be space constrained, but also extremely slow, as every 7th block would be spread across two tracks. 16 sector was done for the Pascal System for the Apple II, independently and before the Apple III got it, but didn't get rolled out for DOS until after the Apple III was introduced (and failed).

Apple ii floppy disk format