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Macintosh IIci ROM Modifications

jmacz

68020
Similar to the modifications I recently made on the IIfx ROM, I've done the same on the for the IIci.

Again, most people will opt for the Rominator or similar custom ROM. But I kind of wanted the stock IIci ROM but with the memory test disabled in order to boot faster. Again, posting this as a reference for anyone interested.

Code:
; Disable the checksum check. Could have changed the checksum
; but decided to leave it in case anything reads the checksum
; and is expecting the stock value. Change:

000435b2 : 4efa 10dc
000435b6 : 4a86
000435b8 : 6600 0360

; to be:

000435b2 : 4e71
000435b4 : 4e71
000435b6 : 4e71
000435b8 : 4e71
000435ba : 4e71

; Disable the memory tests. Change:

000446bc : 4cfa
000447d8 : 4cfa

; to be:

000446bc : 4ed6
000447d8 : 4ed6

; If you want to change the happy mac icon on boot, the icon is at:

000017F2 : 128 bytes (32 x 32 bits)

; and the mask is at:

00001872 : 128 bytes (32 x 32 bits)
 
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