Re: How many K does a ProDOS Apple IIe of IIc floppy hold?

[spec@vax2.concordia.ca (Mitchell Spector)]

In article zeno@magicnet.net writes...

>I had a IIc many years ago, and I ned to know its floppy disk capacity. I
>think it was around 100K or around that, but would like a more exact
>figure. Thanks.

    Each 5.25 floppy disk had a capacity of 140K (143,360 bytes). You
could of course cut an extra notch on the left side and flip it over
for double that, but since the drive was single-sided, as far as the
drive and computer was concerned it was a different diskette.

    Once the disk is formatted there is small bit of space used by
the filing system, leaving about 136.5K for ProDOS disks and a bit
more (or was that less?) for DOS 3.3. This all assumes 16 sectors
and 35 tracks, the original Disk II Controller PROMs worked with
only 13 sectors, but no one has used those since the 70's. So the
answer is 140K, but _slightly_ less to the user once formatted.

Mitchell Spector
spec@vax2.concordia.ca