LisaList2

I've been tinkering with this a bit to develop some tests.

I wanted to dig under the hood a bit for a few things I'd like to work on. I had ChatGPT write a toolchain so that the code can be compiled using the Workbench compiler on my Windows system and then it produces a .image with every thing that boots.

I kicked off a compile on my Lisa 2/5 and let it compare the result so that the output from the toolchain is a byte for byte match with what the Lisa makes and it was.

One thing I wanted to investigate was why Lisa OS I/O feels so much slower than MacWorks. In FILEIO, I found that locating a position within a file repeatedly walked the file's extent map from the beginning. That added more overhead as the requested position moved farther into the file. Changing the lookup to avoid re-traversing the earlier extents helps a lot depending what it's doing.

Another test was to run the same test against the ESFilePro using its RAM vs SD and that netted about a ~10% increase.

The final test I did was using a RAM backed FS (so that the process goes through all the filesystem overhead vs just raw RAM reads) to see what possible upper bounds might be. An actual internal interface would be faster since the extent search eats a lot of CPU cycles depending what it's looking for.

Request size	Original LOS + ESProFile (kB/s)	Patched LOS + ESProFile(kB/s)	Patched LOS + Lisa RAM(kB/s)
512 B	18.58	23.20	31.98
1 KiB	30.28	36.05	57.02
2 KiB	44.15	49.85	93.65
4 KiB	57.31	61.64	137.97
8 KiB	67.32	69.91	180.74
16 KiB	73.78	74.94	213.88
32 KiB	77.48	77.73	235.47

The speeds are good, but the reductions in cycles frees it up for working on what it just received I think will give a boost as well. I'd ultimately like to design an expansion board drive that could do DMA. The Lisa supports it having its own ROM to boot from and having a driver in the OS should let it use it.

LisaEm was a huge help in getting this done for quick tests of ideas.

Quote from: berskyboy on October 27, 2026, 06:56:11 PM

Quote from: TorZidan on October 27, 2026, 06:02:00 PMprocure and install "H" ROMs and its corresponding video ROM

What do I look for to buy?

• A pair of Lisa CPU Board EPROMs, revision H which have Apple part numbers something like 341-0175-H and 341-0176-H
• A Lisa CPU Board Video PROM which has an Apple part number of 371-0072

The programmed contents of these is available on BitSavers, so with an EPROM programmer, you can purchase a pair 2764 sized EPROMs to erase and re-use, but the Video PROM is normally not erasable.

There is an adapter design to use an EPROM in lieu of the one-time-programmable 20 pin bipolar PROM, but I've not tried it.

Note that the Video PROM contains the Lisa's Serial Number, so there are numerous variants of the programmed contents of this part (containing different serial numbers).

I believe you are in Canada with me, so I may be able to provide these; contact me privately to discuss.

Quote from: Lisa2 on March 26, 2023, 05:49:15 PMNote: if switching between the older (H, D, C) and screen mod ROMs (3A) the screen pots really need to be adjusted. The original ROM switcher instructions recommend a compromise of settings between the two setups.   Neither the original ROM switcher nor the Sapient board switch in the yoke transformer for the screen mod. 
Rick

Where can I THROW my Canadian money at to get this ROM switcher?  LOL.

here's my YouTube Video of my Lisa after 2 months of 5 parts and labor and lots of help from this forum.

https://www.youtube.com/shorts/4rsFZumeZo8

I wanna run LOS 3 and Mac XL, Don't we all want our cake and eat it too?

The plan remains to upgrade the Selector in December. I have the entire month off (for this project and for other things).

No, the Selector update alone won't solve anything for LOS. LOS explicitly requires the H ROMs, so you'll have to install them if you ever want to run it. I'm not sure if anyone sells ROMs anymore now that VintageMicros is in the process of moving under new management.

Quote from: mst3k on October 27, 2026, 08:07:28 PMTorZidan has your answer for LOS's.

Then Stepleton's Selector will work too and you can choose just about anything.

ah you mean this will eventually solve it?

Quote from: TorZidan on October 27, 2026, 08:07:28 PMThe Selector eventually will work. We've been waiting for @stepleton to find some free time to "lick that cookie": https://lisalist2.com/index.php?topic=886.msg6973#msg6973

Yes I can wait for that.  It would be nice to have a way to run both! 

Quote from: TorZidan on October 27, 2026, 06:02:00 PMOr you can procure and install "H" ROMs and its corresponding video ROM.

TorZidan has your answer for LOS's. (You need 'H' ROMS).

Then Stepleton's Selector will work too and you can choose just about anything.

Quote from: mst3k on October 27, 2026, 07:38:46 PMGrab a MacWorks image and copy it to your SD card.

Rename the existing profile.image on the sd card to something else.

Change the name of your new MacWorks image to profile.image (no caps).

Boot.

Worked for me.

YES that works!!!

Here's a YouTube Video...

https://www.youtube.com/shorts/4rsFZumeZo8

BUT... how can I get the LOS 3 on it?  Or is that a way more complicated process?

Go here:
https://mega.nz/folder/hxBXXKyA#KQHomG_6NikZonALWmdTCA
(images referenced by Alex on GitHub)

Grab a MacWorks image and copy it to your SD card.

Rename the existing profile.image on the sd card to something else.

Change the name of your new MacWorks image to profile.image (no caps).

Boot.

Worked for me.

Quote from: TorZidan on October 27, 2026, 06:02:00 PMIt seems that you have the square-pixel "3A" rom, which cannot properly display the Selector screen (and LOS), so you are limited to running MacWorks XL and perhaps some unix-es.

The Selector eventually will work. We've been waiting for @stepleton to find some free time to "lick that cookie": https://lisalist2.com/index.php?topic=886.msg6973#msg6973

Or you can procure and install "H" ROMs and its corresponding video ROM.

Ok how do I go about doing

install "H" ROMs and its corresponding video ROM.

What do I look for to buy?  Also will the ESProfile load MacXL?