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[paule]

I just finished cleaning and lubricated the 400K drive in my Lisa 2/10. Using BLU I can Check, Format, Write and Verify a disk with a bootable BLU floppy image. However when I try to boot from the disk, I get a 75 error indicating "System files are damaged" according to Pina. Any ideas about why the disk might be perfectly correct by all tests and yet fail to boot?

[compu_85]

Is your Lisa able to boot from other disks? What ROM version is it?

[sigma7]

Using BLU I can Check, Format, Write and Verify a disk with a bootable BLU floppy image. However when I try to boot from the disk, I get a 75 error

Looking at the ROM listings, error 75 is a result of an unexpected exception when trying to read the boot disk.

Since the disk verified after writing, it seems probable the code would read into memory ok, making an illegal instruction or F-Trap/A-Trap exception unlikely.

Double check that the error still occurs after a cold boot (power off then on and try booting the disk), and make sure that the Lisa isn't inadvertently trying to boot from the hard disk... (press space bar during the self test, then when startup-from menu appears, insert floppy and type Apple-2)

When the exception occurs, some of the processor state is saved by the BTERR routine in memory for later examination in service mode, so that may be the next troubleshooting step.

[paule]

H rom. I hadn't been able to boot any other disks, but given their unknown state I thought I should start from a know good disk.

At any rate it is working now. Previously I had used <Create BLU DC42 image to write to floppy> to create the in-memory image. This is the one that wouldn't boot. Just now I downloaded the BLU090.dc42 image and wrote that to disk, and success! Interestingly, the BLU090.dc42 wrote much less data to the disk than when using the Create BLU DC42 image function. Of course it is entirely possible that operator error was involved in yesterday's attempt.

Thank you for your help sigma7 - hopefully what you said and what I found will be of help to someone else!

[paule]

And thanks for the boot ROM reminder. My 68K is a bit rusty, but I'm loving this :-)

[sigma7]

I had used <Create BLU DC42 image to write to floppy> to create the in-memory image. This is the one that wouldn't boot. Just now I downloaded the BLU090.dc42 image and wrote that to disk, and success!

Congrats on the success!

The problem you encountered is a mystery to me... I don't suppose it was as simple as a data transmission error when transferring BLU to the Lisa... presumably BLU's self check would have reported a problem in that case.

The .dc42 file you downloaded was almost certainly created using BLU's "Create BLU DC42 image to write to floppy" function.

It sounds like you used the correct procedure, so if you figure out what happened do let us know so we can clarify the instructions.

[paule]

I'll try the using the Create image function again to see if I can reproduce the problem tonight.

And THANK YOU so much for creating BLU. What a fantastic too for the community!

[paule]

I used the Create image function last night and successfully created another BLU boot disk. I don't know what happened the first day, but I'm going to chalk it up to user error as I was going through everything for the first time.

[sigma7]

I used the Create image function last night and successfully created another BLU boot disk.

Super, thanks for going back to check!

And thanks also for your kind words.

James