Print

[blusnowkitty]

So I finally tracked down an OEM version of the 1080A, IBM's 3852. Hasn't gotten here yet, but I plan to take it apart and photograph the boards to see if there's any major differences between the 1080 and the 3852 that'd keep me from using it on a Lisa. I can already see that the 1080 has a set of configuration DIP switches on the back while the 3852 lacks them. Hopefully it's just they were removed from the board and the pads are still there. I also wouldn't be surprised if there were ROM differences between the two that can't be fixed by burning 1080 ROMs... More details to come soon.

On another note, anyone got a spare dual parallel port card? I picked up another Profile disk so now I'm running three ProFiles off mine... It feels weird to have a setup that would have cost around $21,000 new or $50,000 today.

[compu_85]

You might find this thread I started on VCFed a while ago interesting:

https://www.vcfed.org/forum/forum/technical-support/vintage-computer-hardware/54535-looking-for-canon-pj-1080a-drivers-software

TLDR, the IBM and Canon printers have very different looking PCBs. I was not able to get the Canon printer to spit out anything intelligible using the IBM driver in Windows.

Note you need to use the "special" Lisa parallel printer cable. IIRC 2 of the status lines are swapped. (The same cable needed for the Apple Dot Matrix Printer)

-J

[blusnowkitty]

Interesting. But it does look like that barring the PCB respin, the only changes are the IBM board lacks the DIP switches and appears to have picked up an extra OTP ROM. They're both still based around a 6809 so I can't imagine the two boards are very different electrically... I also can't imagine the boards being more than two layers, so might be possible to hack the DIP switches back in based on pictures of a 1080A board.

Do we have the pinout of the Lisa parallel printer cable? I can probably build an adapter cable so I can use my normal PC printer cables.

Failing all of the above... I have a traveling computer museum in the works and I can always throw this 3852 on my 5150 or 5170!

[stepleton]

It's not convenient now (this month is very busy, especially this weekend!) but I ought to be able to determine the pinout without too much trouble. I repurposed one of those chunky A-B switches for 25-pin DB-25-terminated cables as a kind of patch panel for this kind of cable-hacking, and while I have no recollection at all of how I determined the correct cross-connections, it works now and that's what counts. It's not too hard to pop the lid off and see what connects where, and I'm happy to do that if nobody else passes along the answer first. Sorry I can't do it right away, though!

[compu_85]

Tom, here's a post you'd made on the old mailing list https://groups.google.com/g/lisalist/c/UkF3J1jNTew/m/ZzL2z20zCwAJ :

"James's change to my adapter --- moving Lisa pin 16 from PC pin 11 (\BUSY) to PC pin 10 (ACK) --- results in color printouts from the Lisa to the Canon printer! "

I posted this link to Apple's tech site, which gave me trouble initially... https://support.apple.com/kb/TA30884

James copied the text into a reply:

Anticipating its disappearance, most notable on that page is this cable pinout:

     P/N 590-0042-B (DMP)

DB25 Connector         AMP36
   (Male)             (Male)
     2 ---------------- 19
     5 ---------------- 2
     6 ---------------- 3
     8 ---------------- 4
    11 ---------------- 7
    12 ---------------- 8
    13 ---------------- 9
    15 ---------------- 1
    16 ---------------- 10
    18 ---------------- 35
    19 ---------------- 12
    21 ---------------- 13
    22 ---------------- 5
    23 ---------------- 6
    24 ---------------- 16
    25 ---------------- 32


I've attached a text file with the pinouts listed on that page.

-J

[stepleton]

Ha, great find! I'm disappointed that I didn't remember that my success simply owed to other LisaListers' helpfulness. Of course I should have suspected nothing else!

[rayarachelian]

Tom, here's a post you'd made on the old mailing list https://groups.google.com/g/lisalist/c/UkF3J1jNTew/m/ZzL2z20zCwAJ :

"James's change to my adapter --- moving Lisa pin 16 from PC pin 11 (\BUSY) to PC pin 10 (ACK) --- results in color printouts from the Lisa to the Canon printer! "

Here's the local link to it: https://lisalist2.com/lisalist1/2329.html

[blusnowkitty]

Alright, so I got my 3852 in today! Unfortunately it is the later revision with the two ROM chips. Initial playing around with it suggests it's not going to be as easy as whacking in a 1080A ROM and calling it good. With the IBM ROM in place (a 27C128), you can remove the OTP ROM and it'll still boot (I dunno if it'll print, but) however, once you slap in the 1080A ROM on either a 2764 or a 27128 (or a 27256), then the printer behaves as if there's no ROM installed - all status lights on.

Based on the pictures over on VCF, it looks like the 3852 has a lot more RAM onboard than the 1080A - I wonder if the start of ROM is in a different place on the 3852 than the 1080A?

On a more practical note, what's a good way to clean out the printhead lines? It looks like old ink dried up in the lines over the years. I'm also wondering what would be a good replacement foam for the black cartridge? I cleaned out mine but when it dried, the foam turned hard and shrunk.

[compu_85]

You could use a kitchen sponge or some other absorbent pad.

The ink is water soluble. You could try pushing a lot of water through the lines if they're super gunked up. I had to do this on a slightly later Canon printer to get it going again that used a similar cartridge and flexible line setup (A BJ130e).

-J

[blusnowkitty]

You could try pushing a lot of water through the lines if they're super gunked up.

I think I need to figure out how to do this. I got the CMY lines working reliably but the K line won't print. If I watch the purge lines on the right side of the lever, the CMY lines are solid with no bubbles, but the K line only shoots out a little spurt of ink and then goes dry again. Interestingly the supply line going to the print head is solid with no bubbles as far as I can tell.

On another note, the OTP ROM is indeed the character ROM. Which makes me wonder if I can pull a Foone and make this printer print in Comic Sans... https://twitter.com/Foone/status/1347408722033745921/photo/1

[stepleton]

This sounds awfully similar to the situation I had with the M line in my PJ1080A last week. That blotting procedure I described did the job for me, but it could be that your problem lies elsewhere in the plumbing.

[blusnowkitty]

Well, it works! K is still a little iffy but it is printing again, and it's printing pretty well for being 40 years old! The VCF thread says that the 3852 ESC codes still correspond to the 1080A's, so tomorrow I'll get off to the electronics shop and see if I can build a Lisa to PC adapter cable.

[compu_85]

That looks really good! The IBM font looks a bit nicer than the Canon one.

You might want to replace the foam "bumpers" on the edges of the mechanism. I used self-stick window gasket for mine. On the Canon the printer recalibrates often by moving the head left as far as it will go.

-J

[blusnowkitty]

You might want to replace the foam "bumpers" on the edges of the mechanism. I used self-stick window gasket for mine. On the Canon the printer recalibrates often by moving the head left as far as it will go.

So does the 3852 I believe.

So I built myself a DMP cable according to the pinout above, and no dice. I'm seeing the same failure method that Tom did back in LisaList1 where the Lisa takes several minutes to error out on printing. Verified that everything is where it should be with a multimeter and nothing. I may try moving 16->10 to 16->11 and see if that does anything - can't imagine it would given the results in LisaList1, though...

ETA: Switched the pins. With the pins switched, the Lisa instantly says that the printer is not connected.

[blusnowkitty]

Does anyone here have an original DMP cable and would they be able to verify the pinout? I'm now curious if the schematic on Apple's website is correct - building the cable according to the document seems to have an error where it says Pin 21 on the Lisa should go to Pin 13 on the Centronics. However Pin 13 on a Centronics is SELECT, where Pin 31 is the RESET line. This seems to be backed up by Tom's work in the LisaList1 thread saying Lisa Pin 21 should go to PC Pin 16 which is indeed the RESET line on a PC-style cable. Once I moved RESET from 13 to 31 I started seeing the printer resetting on power-up. However I'm still not getting any output from the printer even after moving BUSY from 11 back to 10 (ACK) on the Centronics.