@5ad750c8 If you’re interested in rounding out a collection, I’d say it’s worth it. It’s a odd machine, in terms of both how it functions and that it was Apple badged. It’s the same form factor as the original ImageWriter.
I’ve never used period software to plot to it but it’s incredibly easy to use USB to serial adapters to plot to it.
In practice, the biggest issues are the pens are weird and nearly impossible to find. It’s also incredibly slow. The pen holder is essential.
@0922f684 Please do! It's an awesome museum and shop. They carry lots of modern retro goodies like the FloppyEmu in stock!! Let them know you found your way there via me 😅
@96d079fd@16340ea3 Thanks! I have those NMBS modules as well and so far they are the only thing that’s close to working. I have two other sets (OKI and Fairchild) that don’t seem to work.
@96d079fd@16340ea3 Looks like your total RAM is also showing as 128KB just like mine. What type of RAM are you using? Can you share a photo of the board?
@16340ea3@96d079fd Looking at the BOM and the card, I didn't notice that U5,6,7 was S373 and U9,11 was LS373. I got all S373. How critical is that? What did you folks use on your cards?
@96d079fd I have no idea, just that our boards are from the same batch is all I can say at this point. That could mean that our boards have the same issue. More testing to be done! I’m going to try to get access to a working Lisa, hopefully tomorrow.
@96d079fd Oh wow this is interesting— a bus error as well! I’m curious if there’s a fault with these boards?
Does yours have a white silkscreen ID front lower left “42779GY151-190514” ? I think that is a JLCPCB order code.
@96d079fd You have a 512K card to try in another slot with the 2MB card? I tried the 1MB setting with four SIMMs and got what you described. Only when I added four more SIMMs (and not adding jumpers for banks 2 and 3) did I get a picture. There’s something weird happening. I have a video in this thread (starts with color bars) that has both lo and hi tones for comparison.
Using the service menu and the display memory command 01FF00 with a length of 100 shows the contents of memory just fine.
As soon as I cross the boundary into 020000 (say, with display memory 01FF80 length 100), the machine abruptly reboots and beeps twice (lo/hi).
Is this a RAM card problem or a MMU problem?
#AppleLisaClone #RetroComputing
Deep diving into buss error handling by reviewing the previous posts and the Lisa Boot ROM assembly.
http://bitsavers.org/pdf/apple/lisa/firmware/Lisa_Boot_ROM_Asm_Listing.TEXT
If I understand this correctly, memory $282 should hold the address that caused the bus error. In my case, I get
282 0002 0000
which I think is $020000 (high byte is ignored). Does that mean the problem is occurring at position 128kbytes in the RAM card? Not sure how to map that to a component/components yet.
#AppleLisaClone #RetroComputing
Using the service menu and the display memory command 01FF00 with a length of 100 shows the contents of memory just fine.
As soon as I cross the boundary into 020000 (say, with display memory 01FF80 length 100), the machine abruptly reboots and beeps twice (lo/hi).
Is this a RAM card problem or a MMU problem?
#AppleLisaClone #RetroComputing
Deep diving into buss error handling by reviewing the previous posts and the Lisa Boot ROM assembly.
http://bitsavers.org/pdf/apple/lisa/firmware/Lisa_Boot_ROM_Asm_Listing.TEXT
If I understand this correctly, memory $282 should hold the address that caused the bus error. In my case, I get
282 0002 0000
which I think is $020000 (high byte is ignored). Does that mean the problem is occurring at position 128kbytes in the RAM card? Not sure how to map that to a component/components yet.
#AppleLisaClone #RetroComputing
@96d079fd Thanks! The sockets I got from another eBay vendor, but likely the same as the original parts. Wish I got the ones with metal retaining tabs though. The plastic just doesn’t hold up to repeated use.
@a71f39de I suppose that would explain why bit 7 is so hard to reduce because it has more randomness. Would be great to understand the serial number format to assign proper new serial numbers to all of the #AppleLisaClone being built.
Good news is the PROM on the I/O board for the floppy should be the same for all of the clones.
http://www.bitsavers.org/bits/Apple/Lisa/firmware/341-8003-A_f95908934da6460a67abc26c2f0d1553.BIN
@a71f39de Terrific! Good news, both enables on the Lisa are grounded and never change. I have some GAL22V10B on order. I’ll also start working on an adapter board.
I have one set of #AppleLisaClone boards for sale in the USA: the I/O board, motherboard, LisATX board, and card risers/extenders for diagnostics. You provide your own CPU and RAM cards. DM me if interested!
https://mastodon.social/@paulrickards/110928832453750692
@a71f39de That's great progress! You're two terms away from the inner limits of pins 18 and 19 of 16 terms. Reusing other pins sounds like a great solution. I'm new to GALs so I'm not sure how to begin with that.
@5ad750c8@8ff2c4ef Totally worth $100. Hopefully you’ll get pens, the holder, and a capper. Pens can be refilled by drilling a small hole in the side and using a syringe to deposit new ink. Tape then covers the hole.
The language it no more complicated than HPGL (but different). It’s just plain text. I use Python to generate the images and the code to the plotter.
Some progress on the #AppleLisaClone today.
-Received a new COP402 processor to replace the COP402M (microchannel version).
-Replaced the two new W65C22N with real MOS 6522 chips (from a 1541 floppy drive!)
-Replaced a 74HC132 with a proper 74LS132 (IO board clock).
With that, soft power now works the way it should!
Next problem: it gives a single beep at startup with a scrambled screen (see video). Fault: CPU or RAM?
#RetroComputing
https://files.mastodon.social/media_attachments/files/111/071/203/645/400/593/original/11fd5526fd3828e9.mp4
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