Okay, after some more testing I don't actually think it's a problem with ESProFile.

I went back and tried it with my original parallel card again, and it doesn't work with that one either. I think I had just never tried switching images to LOS in the Selector on that one before, so I never saw the problem and thought it was working fine. So my guess is that the parallel card itself isn't the problem either.

I'm now thinking that the issue might have something to do with the way that the Selector boots from slot devices. I went through and double-checked that the entire first block is being read from ESProFile into the Lisa's RAM properly, and it's a perfect match, so it has to be something on the Lisa side of things. And the only thing I can really think of on that end would be the Selector itself.

When the Lisa ROM boots from the parallel card, it loads and executes the parallel card ROM code, which handles loading that first block from the disk, whereas the Selector doesn't use the parallel card ROM at all and just loads the block directly into RAM itself. It makes sure to load a copy of the parallel card ROM into the proper place too, but I don't believe this ever gets executed; the Selector just bypasses it and jumps straight to the boot block code anyway. So it's probably that something isn't being configured properly thanks to the parallel card ROM never being executed.

>> AlexTheCat123 said:

Yeah, the ROM that I link to on GitHub is the same one that I've tested. And interestingly enough, I've been able to replicate the Error 49 problem using one of my other parallel cards. It's the same ROM revision, so I guess it has to do with the hardware, but there aren't multiple different hardware revisions of the card as far as I'm aware. So I don't know what's going on. After some investigation, it looks like the disk image isn't getting corrupted at all! It's just that block 0 gets loaded into the Lisa's RAM incorrectly. And it's only when you try to boot straight into the image from the Selector that this is a problem. If you get the Error 49, you can just try starting up from the disk a second time in the Startup From... menu and it'll work fine. Alternatively, you can choose S)elect in the Selector instead of B)oot, then exit to the ROM Monitor, and start up from the disk using the Startup From... menu there. So we've got a pretty easy workaround, but I'm definitely going to look into it more to see what's going on here. Click to expand...

Interesting. I didn't think that to try the reboot with the disk image loaded. I always would reset the ESprofile to get back to the selector image. But I'm glad it's not only me, and that there is an easy workaround. Let me know if there's anything I can do to help.

I know I still owe you a new 3d printed case for the new external version of the PCB that has mounting holes). My 3D design skills aren't quite good enough that I feel confident in a model without having the actual board to test fit. Although I think someone mentioned the ability to import boards into TinkerCAD, so I'll see if there is a way for me to do that so I can feel better about the placement of the mounting standoffs.

I'll let you know if I end up discovering anything else, but I'm pretty confident that the issue is Selector-related at this point!

I've never used TinkerCAD, but I'd be shocked if it didn't let you import Gerber files. That's certainly a lot cheaper and more convenient than ordering new boards!

>> AlexTheCat123 said:

I'll let you know if I end up discovering anything else, but I'm pretty confident that the issue is Selector-related at this point! I've never used TinkerCAD, but I'd be shocked if it didn't let you import Gerber files. That's certainly a lot cheaper and more convenient than ordering new boards! Click to expand...

Surprisingly, it is not possible to do. I was able to use a Gerber to SVG online tool to make an SVG, and import it into TinkerCAD, but the scale wasn't preserved, so I had to scale it in a way that looked roughly correct. I made a DIY version of your PCB with holes by drilling my own, and it worked quite well with 2mm screws. It didn't look like the holes were big enough for 3mm screws, so I made the screw standoffs smaller for 2mm screws. They seem to hold well with my 2mm screws I had to cut down.

Here's the new case bottoms (vented and solid):

Wow, that's pretty shocking! But it looks like you scaled it properly because I did indeed design the holes for 2mm screws. I'll try and print out your new model in the morning.

Thanks again for going to the trouble to design something like this!