OS 8.0/8.1 for 030 Macs
After a few modifications of the 'system suitcase' you can run OS 8 on 030 Macs.The necesury modifications are laid down on this page. Please read the Patch Info.
Additional information can be found on the Home Page of Gamba.
Important : You can not install directly on your boot disk. A second disk is needed. A Zip or anything similar will do too or you can create a disk image (60MB) with 'Disk Copy'.
The availability of a OS 8 Installer disk or a (full) backup is taken for granted.
Change the corresponding entries for hardware-recognition in the resources 'boot', 'gbly' und 'gusd or replace the resources.
'gusd' is not solely a hardware selector. The system checks here if the gestalt ID is present and loads the corresponding resources from 'gtbl'.
Attention ! A missing gestalt ID will stop the system !
Caution ! A missing resource for gtbl ID (00yy) will force the system to hang !
Now : The 'gusd' entries consist always of groups of 4 bytes (= 2 words). The first word (2 bytes) is the computer's id code, the second word points to the block which is up
for loading in 'gtbl'. Via this 'gtbl' entries the specific system adaption will be done.
If the needed resource id in 'gtbl' is not present, the use of id 05 or id 06 will be a good choice.
If you are a real mac software hacker/developer you can write a new gtbl-res but you won't get around changing further resources.
The patched OS 8 was accepted by a Mac IIci with 32MB RAM and ran - a bit labourious though - pretty well.
After increasing the Finder's 'SIZE' resource (min: 262144 bytes, pref: 1310720 bytes) all ran as usual.
And again : 8 MB RAM aren't enough. The system occupies 5 MB after the start and expands during work.
Well, 16 MB RAM are recommended if working should make some sense .
Virtual Memory should be used only if the system fits completly into RAM with a couple of MBs to spare.
Otherwise the Mac is occupied to shovle his OS to and fro the hard disk an working becomes a drag.
If you ever worked with OS 7 on floppy disks you can get a rough picture of it.
OS 7.6.1 'boot','gbly'