On Sat, 17 Jun 2023, Steve Lewis wrote:
My only question is: how "universal" are
8" disk? This 5120 only came with
a single IBM 8" Diagnostics disk. It looks to be in fine condition, but
I've no idea about the data.
I can answer your question very quickly:
A 5120 is exactly the same as a 5110 plus 5114. This said, the diagnostics
and any software apply to both systems.
You can take any 5110 floppy image and recreate a real floppy from it. The
format BTW is "the" standard IBM format. The 5114/5120 can handle
everything from single-sided single-density up to double-sided
double-density. The firmware OTOH has a predefined set called "formats",
ranging from 1 to 9, with an optional suffix indicating the number of
additional directory tracks (only available with DD). The list is
somewhere in the manual, e.g. format 1 is SS/SD 128 bytes/sect. 26
sects/track, and format 8b (b=blank) is DS/DD 512 bytes/sect. 15
sects/track.
IIRC format 1-3 are SS/SD, 4-6 SS/DD and 7-9 DS/DD
Christian