LisaList2

Rick,

I still have not had time to build a chip tester.

If your offer is still open, I would like to send you the card for diagnostics.

Quote from: bmwcyclist on June 06, 2025, 11:14:31 am

I just recieved a new Sun Remarketing Lisa SCSI card from Vintage Micros.
The card looks great but it is giving me a Card Error 92 on bootup.

bmwcyclist,
I am sorry you are having issues with this board from Vintage Micros.  Normally these boards are very reliable, you should not have deal with this much trouble to get it going.

On behalf of Vintage Micros, I will repair or replace your defective SCSI card.  Please PM me and we will get you fixed up.

Thank you,
Rick

I actually think you are right! But this might not be a 2/10 IO board, but a 2/5 board. Just not the common version that we see

I'm pretty sure this is a 2/10 I/O board. 820-4033-A, the IWM chip up at the top left corner --- it's just like the one in my 2/10.

I actually think you are right! But this might not be a 2/10 IO board, but a 2/5 board. Just not the common version that we see

Had a chance to clean the rear / upper head and remembered to take before and after photos while the alien was off, below. Disks shed their debris mostly on one side of the head, and it can be tricky to remove entirely. A bit of elbow grease, 99% alcohol and a swab should do the job. If cleaning the rear / upper head, I would suggest steering clear of the lead screw lest you remove its lubricant. If you do, I understand Tri-Flow lubricant is recommended in Apple documentation.

The last image is an example of a clean drive head in the front / lower position. Should be a nice clear, white octagon.

it came from eBay this way and I assume the machine must have been in a working state

It is certainly possible that I'm wrong that it shouldn't work (or maybe there are more specifics as to where it does and doesn't)... can someone else comment on this:

Does a mechanical 400k/800k floppy drive work in an otherwise normal 2/5, except with a 2/10 I/O Board installed?

edit: from a brief experiment, it seems an 800k drive will work, while a 400k drive does not.

Part of the motherboard

Here is a picture of the IO board

What is strange is that it came from eBay this way and I assume the machine must have been in a working state before and not modified after. It has a "Lisa is now Macintosh XL" sticker in front, H/88 ROM and a switch to toggle screen height (I assume to work with MacOS and Lisa OS)
Even though the original drive is stuck it was plugged into the lite adapter and the red light works

Re-installed the drive and it works!

Nice work; you're quickly becoming a Twiggy expert!

The weird part is that my floppy drive was working just fine with floppyemu

I have a vague recollection of someone mentioning this phenomenon before, so there are clearly some holes in my logic/understanding/memory.

I presume the FloppyEMU works in that case because it does not need the motor speed signal. AFAIK, it can determine the virtual speed based on the track number, and I suppose it doesn't need to vary anything at all in that regard, since the change in RPM is only to make the flux change density on the magnetic media more consistent, so the digital rate remains the same regardless.

Now I wonder if there are further consequences, such as:

• is it the case or my imagination (or hallucination -- I promise that I'm not AI) that the superdrive doesn't use the motor speed signal? If so, will it work in this configuration even though 400K and 800K drives don't? (Don't try it if you don't know... maybe the wiring isn't compatible in some way)
• does the same effect mean that a 1/5 I/O Board will work with a FloppyEMU and 2/10 motherboard and chassis cabling?