Apple Lisa Booting in MESS

MESS has an Apple Lisa emulatorin it, but it is not complete and therefore will not boot the LisaOffice System. It will boot MacWorks, but nothing else.Nathan Lineback's GUI Galleryhas his images of MESS attempting to boot various Lisa operating systems;here are mine. I have gotten the Lisa OS to boot into MESS as far as itcan possibly go, which is a little farther than what he has. I have alsodone enough research that I know what the emulator is failing on and whythe Lisa OS refuses to boot.

The Lisa emulator starts up.

The first error message we encounter in the Lisa's self-test. Thenumber 42 indicates a problem with the serial port. This isn't sobad, as far as I know; it just means we couldn't use LisaTerminal.Instead of going right to Startup From, we can choose Continue.

The Lisa emulator continues its self-test. It takes quite a whileto scan the RAM in emulation.

The second error message. Number 55 indicates a problem withvideo. Unlike the serial port problem, this one is critical andultimately the reason Lisa OS won't boot. We can still chooseContinue.

At this point we reach the Startup From menu where we can choose adisk to boot from. The disk drive MESS provides is #2.

I actually was able to feed it a Lisa disk in the right format.From this screen, it appears as if the emulator is attempting to bootup the Lisa OS!

Nathan Lineback'ssite has a screenshot of error 23, which means the disk is not in the rightformat.

Unfortunately, this is as far as it can possibly go, and we crashwith this weird 10201 error; this code is undocumented, and mostlikely doesn't mean anything specific.

Now, the reason why the Lisa OS will not boot in the MESS emulatorhas to do with its strange copy-protection scheme. The Lisa OS tiesitself to the Lisa machine it is running on, in a similar manner tothe individual tools. The Lisa actually incorporates its serialnumber into the video stream (hence the mysterious "Video State ROM"that contains just the serial number). The Lisa OS reads the Lisa'sserial number from the video stream; if it can't read the serialnumber, it refuses to boot. Error 55 indicates that video is notemulated properly, so the Lisa OS can't read the video stream, so itcan't determine the serial number, so it refuses to boot. This isalso what makes the square pixel mod and certain CPU acceleratorsbreak the Lisa OS software.

The MESS systemstatus for the Lisa emulator says that the MMU is still buggy.The MMU certainly has its hands in accessing the video stream fromsoftware, so that is certainly part of the problem. There is no wayfor me to know if it's just the MMU or both the MMU and the videothat are causing the Lisa OS to fail.