mejs

mejs, 18 days ago

Beyond this, the ROM version in the upper right now shows H/5F instead of H/8F (not sure if any significance). Even with this second floppy option showing (technically, it's "1" that showed up, "2" was visible earlier), my FloppyEMU doesn't do anything when selected and it fails to boot with error 39 as before

mejs, 18 days ago

Ok this is really esoteric computing, but I actually managed to start booting from a floppy, for a second...

#lisa

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mejs, 18 days ago

Woot I can get it to boot and crash!

#lisa

mejs, 18 days ago

So I'll try to explain what's going on here, but like I said it is esoteric. I'm more and more convinced that the primary issue here is with memory, in addition to the actual SRAM problem on the IO board which I fixed

#lisa

mejs, 18 days ago

I'm using the 2MB RAM card in this Lisa clone. However, it only successfully boots with 512K.

If I put 1MB, and set the jumper, it will get a memory error.

However, by booting it once with the jumper, and then taking the jumper out and rebooting, I managed to somehow get it to a state where it actually tries to boot from floppy and partially succeeds 🫠

#lisa

mejs, 18 days ago

Okay it's not really what's supposed to happen but I still think it's kind of neat

#lisa

mejs, 18 days ago

@paulrickards yup, I do have it, and I think the fact that I can trick the Lisa to actually boot from floppy suggests that the ROM is being read fine

mejs, 18 days ago

So somehow I actually got a stable boot into Macworks

#lisa

mejs, 18 days ago

@paulrickards thx!

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mejs, 18 days ago

@paulrickards do you mean this one?

mejs, 18 days ago

I wonder if this is a sign?

I'm now at a point where I can actually boot into Macworks pretty reliably, with 1MB of RAM and ignoring a memory 70 error (+ soft resetting once after cold boot). So it's a bunch of heuristics, but it kind of gets me in.

It's weird thought that finder reports 2MB of RAM. Maybe this is a hint that the system thinks it should have 2MB even though my jumpers are just set for 1?

mejs, 18 days ago

@paulrickards I can boot the 400k boot image, but it then crashes at the point where I need to insert the 800k one

mejs, 18 days ago

So, a #lisa update.

Thanks to a super helpful tip from @DosFox, I now know that the sunrem 2MB card needs SIMMs in slots 1 and 4 to have 1MB, and not 1 and 2 as I originally had them.

The current process right now is:

• on first boot memory test will pass, but IO fail with error 57. I can't boot to floppy
• soft reset makes it pass all tests and let's it boot from floppy

Otherwise:

• I still can't go beyond 1MB
• there are still some wrong keyboard keys
• ArduinoFile doesn't work

mejs, 18 days ago

So the consistency of getting rid of error 57 by soft resetting suggests that maybe the issue is with the /RES line not getting triggered on cold boot

mejs, 18 days ago

Yup, that's it. I've verified this with oscilloscope and then manually triggered reset at power on, and it passes the IO test without the error. Looks like the problem may be transistor Q11

mejs, 17 days ago

An #applelisaclone update:

• still working on properly triggering the reset line on cold boot, but manually soft resetting works fine
• still some RAM inconsistency with 1MB so went back to 512K. It could be the slower 74LS20 instead of 74ALS20 as suggested by @paulrickards
• most significantly, I now have the ArduinoFile working - you may remember, I messed up the gender of the parallel port. Turns out the gender changer adapter flips the pins for some reason so I had to manually wire it up

Prompt to select Startup device with images of a floppy and disk drive

mejs, 17 days ago

I may now need to go and finally deal with my finicky keyboard, because I can't even use the key "b" to boot from selector (even if I had working keys to select another image)

This is the selector software: https://github.com/stepleton/cameo/tree/master/aphid/selector

#lisa

mejs, 17 days ago

And after about 2 months of building a Lisa from scratch, I am booted into Lisa Office System 3.1!

#applelisaclone

A desk window showing files on the apple Lisa drive

mejs, 17 days ago

Okay the Lisa is weird

The dialog messages are bizarrely unsettling. The lack of clarity. The weird italicization.

It's familiar and unfamiliar at the same time.

#applelisaclone

Please reinsert the Lisa Office System 1 micro diskette at this time. The Lisa will not be able to finish installing the Lisa Office System software until the Lisa Office System 1 micro diskette has been reinserted.
Preferences has been told that there is an expansion card in slot 2, but there is actually no card in this slot.

mejs, 17 days ago

How am I supposed to "install" LisaDraw to the hard drive? I was able to drag LisaWrite without a problem, but I get this error with every copy of LisaDraw

#lisa

mejs, 17 days ago

I guess I need to either deserialize the floppy or a find a copy that's not serialized

https://www.cs.oberlin.edu/~jwalker/lisa-legacy/

Edit: no I don't, I just need to duplicate the files before dragging them 🤡

mejs, 17 days ago

Welcome to 2024, Apple Lisa!

#lisa #applelisaclone

mejs, 17 days ago

Like I said, the Lisa Office System has attitude

Italicizing "w" in "want" just to feel something

mejs, 17 days ago

After a brief interlude actually using the #applelisaclone, I'm back working on the issues punchlist. I really want to get the keyboard running, and I'm struggling to understand how it actually works.

(I'm pretty sure my issue is not the pull down resistor. I experimented with a bunch of values both below and above 3.3K and the results are exactly the same).