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[no subject]
It depends, but 256K per disk is the safest answer, for IBM 3740 Format.
My 8" setup had the SVA DISK 2+2 controller with Shugart SA800/801 drives.
It could handle four drives under Apple Dos3.1 or 3.2 (also Apple Pascal
and Dos3.3. Note: unlike DiskIIs, capacity did not change between Dos3.2
and dos3.3 or Pascal.)
IBM 3740 format: 77 Tracks
36 Sectors/Track
128 Bytes/sector
============
256,256 bytes total (2.2 times the capacity of dos3.1/3.2
diskII) Recording technique was FM, single density.
The SA800 drives were single sided, the SA850 drives were double sided, with
twice that capacity, but I don't think the Disk2+2 controller supported
double sided disks.
Thus, SVA introduced the ZVX4 Megabyter controller. It supported 1 and 2
sided disks and single and double sided disks. So with a ZVX4 controller:
SA800 SA850 SA800 SA850
Format
Tracks 77 154 77 154
Sectors/track 26 26 48 48
Bytes/sector 128 128 128 128
Recording technique FM FM MFM MFM
Density Single Single Double Double
Heads(sides) 1 2 1 2
Media (IBM diskette) 1 2 1D 2D
Storage/drive (bytes) 256k 512k 473k 946k
Max # drives 4 2 4 2
Max storage/ZVX4 1024k 1024k 1892k 1892k
Data transfer rate 250k 250k 500k 500k
(Date transfer is Bits/second, not "bytes/sec")
So in re-answering your original question: 256k, 473k, 512k, or 946k
were the capacities for 8" diskettes.
But at that time 256k/disk was a dream for Apple Pascal programming.
All system files from Apple0:, Apple1:, needed Apple2: and Apple3: fit on
the boot system disk, and my programs fit on a second disk on a second
drive. No floppy shuffle. It was nice.
Later,
--Steve
--
--Steve (apple2pd@ground.ecn.uiowa.edu)