English Amiga Board - View Single Post - A500 won't work with official (MX) 2.04 ROM

r.cade · 13 November 2021, 00:30

This particular A500 (Rev.5) has a problem where it won't work even with an original Kickstart 1.2 ROM.

I built the adapter board with the 4.7k resistors that is supposed to fix the issue with EPROMs on A500, and now the original 1.2 ROM works, and the 2.04 ROMs also all work fine.

Bizarre... It only works natively with the 1.3 ROM that came with it. That 1.3 masked ROM looks identical to the 1.2 ROM, other than the 1.2 is part number -01 instead of -02 on the 1.3.

13 November 2021, 00:30	#7
r.cade Registered User Join Date: Aug 2006 Location: Augusta, Georgia, USA Posts: 550	This particular A500 (Rev.5) has a problem where it won't work even with an original Kickstart 1.2 ROM. I built the adapter board with the 4.7k resistors that is supposed to fix the issue with EPROMs on A500, and now the original 1.2 ROM works, and the 2.04 ROMs also all work fine. Bizarre... It only works natively with the 1.3 ROM that came with it. That 1.3 masked ROM looks identical to the 1.2 ROM, other than the 1.2 is part number -01 instead of -02 on the 1.3.