Jonathan Adams wrote:
I know that ProDOS 2.X and later won't work with a II plus. I have been
trying to boot earlier ProDOS versions, such as 1.4, 1.1.1, etc. I tried to boot the ProDOS User's Disk and it locked up, even though the label says that it works with a 64K II plus (My clone has 64K on the mainboard, unusual for a II plus clone). The only ProDOS program it will boot is copy II plus.
Maybe some of your RAM above 48K is unreliable? Does Integer BASIC work correctly when you boot a DOS 3.3 Master? Do games that use the upper RAM a lot, like e.g. Ultima IV, work correctly?
-- Linards Ticmanis The Master said, "The business of laying on the colors follows the preparation of the plain ground."