Macintosh IIcx custom ROM

[luRaichu]

Hi,
I'm looking for a IIcx compatible ROM that only has the memory test disabled and is 32-bit clean. The examples I've found include a ROM disk which I don't want or care for. Thanks

 

[frontein1]

My IIcx is down for the count right now. But you can drop a IIsi ROM in the IIcx. This would give you a 32-bit clean ROM.

So really you probably want a IIsi ROM with just the memory test disabled (and vicariously the ROM checksum altered to not fail) right? If so give the attached a run (assuming you have a SIMM and a programmer handy)

 

[Bolle]

This will do: https://68kmla.org/bb/threads/macintosh-se-30-rom-modifications.49789/
IIcx and SE/30 have identical ROMs.

Edit: a scratch that, I missed you were looking for 32-bit "clean" ROMs.

 

[Joopmac]

I know of and use this one http://synack.net/~bbraun/macsrc/iisi+romdrv0.9+nomem+nosum.bin
IIsi 32-bit clean; No ROM disk, and no RAM test
see http://synack.net/~bbraun/macromboot.html

 

[luRaichu]

So really you probably want a IIsi ROM with just the memory test disabled (and vicariously the ROM checksum altered to not fail) right? If so give the attached a run (assuming you have a SIMM and a programmer handy)

Why is it double the size of a IIcx ROM?

 

[croissantking]

Why is it double the size of a IIcx ROM?

The IIcx ROM was older generation, whereas the IIsi was a newer universal ROM, so it was expanded.
Apple doubled the size of the ROM several times between 1986 and 1998, eventually ending up with 4MB ROMs.