[Coco] 1.2 MB Floppies (again)
lamune at doki-doki.net
Thu Aug 3 21:28:12 EDT 2006
Robert Emery wrote:
> Actually, interchange between 35/40 track disk systems is not problematic at all. When the CoCo is patched to see 40 tracks, it will still read/write 35T disks. The only problem I was aware of would be if a file was written on tracks 35-39 and attempted to read on a 35 track system, obviously it ain't gonna happen. There was a tool included with the Track patching utility that would mark the top 5 tracks as used so you could safely use it between both systems.
> 72 or 80 Tracks could also be patched into RSDOS, but this is where you start getting into real compatibility concerns. I was happy enough with 360K per RSDOS floppy that I only formatted one 80T disk, full 720K under RSDOS, holds a boatload of Basic! Just not compatible with anything serious that tries to do it's own I/O, whereas a 40T disk generally will still work.
The interchange issue in DECB is that the recipient of the disk must
also be patched in order to read the stuff on the extra 5 tracks.
That's what I was getting at, as there is no physical interchange issue
between most CoCo "35 track" drives and 40 track ones.
Only the really early ones are physically limited to about 37 tracks or
so, and thankfully most of those are dead by now.
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