Skip to main content
Home Forums 68kMLA Removing startup artifacts of "improved" ROM SE/30!!! — #23
Post #23 by dougg3
Source Forum68kMLA
CategoryTroubleshooting
Post DateSun, 4 Nov 2012 - 01:04
Original URLhttps://68kmla.org/bb/threads/removing-startup-artifacts-of-quot-improved-quot-rom-se-30.25600/
Post
Hey Zuiko,

Thanks for running that test! So the SE/30 also has version 0 it seems. Nevermind about the differences I mentioned.

That's weird that $802 is reading back as 2. On my IIci, it reads back as $80. I'm not too concerned about what it reads back as in the Mac OS though--if the version register at $800 is reading as 0, then we know what code path it's going to take in the ROM. Also, your tests of the Sound control panel serve as a good confirmation.

I wonder if there's some kind of GPIO initialization that needs to be done in one of the VIA chips. I think GttMFH lays out what the registers do in each VIA. It's possible for a death chime to play very early in the boot process, so there can't be much left to initialize :-)

The SIMM should work in all of those, but I don't know if the newer sound chips in the IIsi or Quadra 700 will be register-compatible. I would assume the IIsi will still be compatible, but I'm less sure about the Quadra. I'm thinking that the FIFO status registers act differently on the Quadra's sound chip. I guess there's only one way to find out...

mp.ls