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Farallon ETHERMAC LC NSC w/NuBus drivers in the SE/30 PDS?

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Thanks for the offer. I've got a pair of DOA LCs I mostly got for hacking the case lids long before the caps issue came to the forefront. They may be good after all?

 

Popped the lid on one and it's PDS is well marked on the silk screen layer. Checked the DOA SE/30 board (got it in trade from someone who borked it in a recap attempt) is marked the same manner. Never realized there was a "Mirrored Z" patterned number scheme for the pins from pin 1 @ 1A to pin 32 @ A32, then over to pin 33 @ B32 and back from there pin 64 @ B1 and finally over to pin 65 @ C1 and up to pin 96 @ C32. 68030 PDS is the same deal with 120 pin. Always bothered me that the columns weren't labeled A-B-C for grid reference on the boards, but now I know how it's done. [:)]

 

Spudged the wrap map from the connector side with the help of a top coat of it as a solvent. Which bring a question to mind:

 

Does anyone know if Elmer's Rubber Cement is at all conductive or a good insulator? Figured it'd be the latter, but now I have need to know.

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So many capacitor issues, seems to be the bane of the hobby.  Interesting question about Elmer's rubber cement.  I, of course, could not answer that.  I would *think* it would be a good insulation rather than conductive.

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22 minutes ago, maceffects said:

So many capacitor issues, seems to be the bane of the hobby.  Interesting question about Elmer's rubber cement.  I, of course, could not answer that.  I would *think* it would be a good insulation rather than conductive.

Plop some down on a piece of paper, let it cure, and test it with a multimeter. But I highly doubt that it will be conductive.

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Figured that wasn't definitive for testing logical level shortages when contaminants might be involved. Now I remember I might have found my preferred can of 3M Super 77 spray adhesive for application #2. Didn't think things all the way thru or do my usual level homework error check/editing in my haste to get to the wrapping.

 

Worst possible case would be a fresh start with a new board on hand, not crazy about reliability issues of a 1/2 to 3/4 level wrap on soldertail pins when it comes to stripping all the wires on one end while wrapped at the other. Tending toward re-boot ATM, practice makes perfect, no? ::) Might even be faster when done more methodically than doing re-work.

Edited by Trash80toHP_Mini

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@Bolle How about that jumper modified address inversion circuit diagram/wrap map layout in PCB format for $9 and $A? Impending Monday arrival of wire wrap sockets for my Mon-Tue weekend allows wrapping that circuit form right from the start and doing a temporary straight connection for research on a second wrap level on proper wire wrap pins for later removal. While waiting arrival of a proper assortment of ICs to be sourced after you come up with some alternate specs I can get er' done the right way.

 

Kit's packed up for stripping it all off for a fresh Perf Board reboot in down time at work tonight. Here we go again! :lol:

 

This time pin key only is going on the adapter with 77 and the integrated wrap map and logic schematic will be on cardboard bolted up to the solder sides of NIC and SuperMac adapter to in iterative layers keep it all together well enough for posterity. :approve:

Edited by Trash80toHP_Mini

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Actually no need for 3 state outputs, just do it like this with a 74LS04:

 

1196966983_Bildschirmfoto2019-04-28um11_52_26.thumb.png.c1c09c44753c15ca3ee5bd71cecc45a6.png

 

Blue is coming from 030 PDS, red is going to LC PDS.

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Sweet. That'll cover both $9 and $A? inversions? How should I document the jumper settings on the board? Can I leave the unused inverter's lines floating? Doesn't look like it's be a problem from the diagram of the 04, but may it be a "best practices" kinda deal to nail them to ground?

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Tie the remaining inputs to ground if you want to do it by the book, it shouldn't matter though.

 

If you put a jumper between 1+2 you will get the normal non-inverted address line.

Putting a jumper to 2+3 inverts that address line.

 

For $9 you invert only A22, for $A you invert all three lines. Of course you will have to wire up the interrupt accordingly to the address inversion you choose. Could add an other jumper for that or do it by hand.

Edited by Bolle

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Thanks, I'll get the graphic set up in the new board key. I've got the address lines jumpers set up and documented already. I'll be posting a new wrap map diagram for error checking tonight.

 

@maceffects  I'll include instructions on how to check its accuracy. You don't need to know anything about the signals themselves. It's but a comparison of the grid locations from the LC side to the table, reading off the mapped grid location from the table and checking that grid location on the 030 side to make sure the text matches the text on the grid location where you started.

 

It's The Imitation Game of PDS association. [;)]

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@Trash80toHP_Mini Sure, I'd be happy to help check connections if you can give me detailed instructions as to what I would need to do.  Likewise, if this one works, I'd like to wire wrap and test the SE version using the prototyping card I have for that machine. 

 

@Bolle That looks great, a good solution.  I'm always amazed to see what can happen when a couple of really intelligent hobbyists.

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From this:

 

BeautifuLoopiness-TwistedMess.thumb.JPG.3733b2d1311125490d77deaa322f4b18.JPG

 

to this:

 

shescomeundone.thumb.JPG.ca4ee9f058c417825e02a8c3518ec2ec.JPG

 

32 Data lines left to unwrap and clip, but I'm gonna miss the luscious loopiness of the FUBAR version. :mellow:

 

Address(Yellow) and Control (Blue) lines will wind up looking much like the straight across the board loop of the Data (Orange) lines that have yet to be unwapped for correction when wrapped to the proper end of the 030 PDS. Decided I can strain relief the bundles and strip in place so I won't have to start over with a new PCB. I'll work around my adhesive contaminant concerns with liberal application of larger drill bits or adding one of the small prototyping cards on hand into the mix as a daughtercard. Leaning toward the latter. Bit of good news though, the jumpered address line length is much reduced so shortening everything up will still keep the traces "meandered" and easily reworked. I'm almost tempted to go ahead and solder the wraps columns A & C on the LC side while they're exposed.

 

ATM the glass is no longer borked or even looking 3/4 empty, maybe a tad over 1/2 full? :blink:

Edited by Trash80toHP_Mini

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Well, at least it looks like you can reuse the connections on one side. Once we get this version tested, I have some fun new toys to try out!  I am very confident we can make this a reality. 

s-l1600.jpg

IMG_5264.jpeg

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Sweet wrap tool! I looked at those a while back, but they were too pricey for me at the time. The flip side of that coin is a heat wire stripper that conserves integrity of the wire. Manual, bladed strippers aren't nearly as good. That SE prototyping board looks fabulous, but source a RA Wrap Connector for your slot connection. You'll be using an SE/30 type SE chassis with the adapter board installed vertically for testing one way or the other. With drive cages removed the pins can point inward. If they're outboard like my adapter, you'll need to do it in a chassis free bench setup, which is what I already have set up.

 

 

Your confidence in this is heartening, I'm still thinking along the lines of my very first statement in the IP: Dunno where this one will lead, but gotta give it a shot. :approve:

Edited by Trash80toHP_Mini

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5 minutes ago, Trash80toHP_Mini said:

Sweet wrap tool! I looked at those a while back, but they were too pricey for me at the time. The flip side of that coin is a heat wire stripper that conserves integrity of the wire. Manual, bladed strippers aren't nearly as good. That SE prorotyping board looks fabulous, but source a RA Wrap Connector for your slot connection. You'll be using an SE/30 type SE chassis with the adapter board installed vertically for testing one way or the other. With drive cages removed the pins can point inward. If they're outboard like my adapter, you'll need to do it in a chassis free bench setup, which is what I already have set up.

Yeah, I picked it up for $20 so can't complain!  I considered electric ones, but really this is a one time project.  I will be doing the testing without the guys inside the machine.  I want to examine what kind of options there might be fore a breakout of some kind.  I like the 96 pin connectors are like 20% the price of the 120 pin connectors. 

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Just be careful about the 96 pin connectors for wire wrap. LOTS of them have only the 64 pins in columns A & C implemented. I got some of the crappy ones before I learned that 96 pin connector doesn't necessarily translate into 96 connections. 64 seems far more common than 96 in available EuroDIN for wire wrap.

 

Anybody know what application two of three row DIN connectors are used in today, aerospace?

Edited by Trash80toHP_Mini

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030 PDS connectors are expensive, which is OK as most SE/30 fanatics are willing to spend a little money where the SE/Plus/Classic lovers are more frugal and willing to live with settling for AppleTalk/PhoneNet. If the NIC will work in the SE, there's no reason I can think of offhand why Plus and Classic adaptations wouldn't work.

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Yeah the expense for producing the PCB, parts, connectors, and assembly puts the cost fairly high.  Still much cheaper than any alternative (way less than half).  I was originally thinking, this would be a cheap board to build, wrong!  I better stop thinking of all the possibilities because I want to build for every machine then, ha!  Next think you know I’ll try to use the LC PDS NIC in Apple II machine. :lol:

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When all you have is a great big bag of hammers  .  .  .

 

All connections have been unwrapped, clipped to length and stripped. Errant graffiti cleaned off the board and it's ready to go for round two  .  .  .  AFTER I finish the homework. ::)

 

strippeddownnreadytorock.thumb.JPG.960c6220b6e560cccfd8f8a893e0a20a.JPG

 

Tried to use the cheapo stripper on the right and went back to the one on the wrap tool after borking a couple of wires. They've been replaced and I'm looking at how best to use a section of the Perf/PCB with the socket on it as a daughtercard for the inverter setup.

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Fun part has already started. I ordered a quartet of 74LS04 inverters last night. I've spent the morning prepping the board for installing headers and socket directly to it w/o any possible electrical contact to adhesive residue.

 

-  gunk removed with good ole' WD40

-  cleaned that residue up with isopropyl alcohol

-  drilled out the perf holes so the thicker standoff base of the socket make no contact

-  used a larger drill bit to countersink the holes on both sides to remove copper and FRP surfaces for insurance

-  drilled out the perf holes again for the socket with a larger bit adding yet more clearance. That should ensure the holes are bare FRP with no possibility of contamination duing previous steps

-  set up the two rows of long headers so they're configured in triads as above with gaps in the pins so no arrangement of headers can short address lines

 

Socket-Headers-Inverter-1.thumb.JPG.0f182da68fac99a3ded0d092af9d07a4.JPG

 

There are plenty of holes cleared in case we need a more complex logical intervention. A 20 pin socket can be installed or beaucoups headers if more contacts might be needed for installing a daughtercard. Outside of a tiny blister trying to develop on my thumb from manually twisting the bit in countersinking all those holes, all is good. Due diligence time, back to doing homework for error checking when I get a chance. I've got SAT/SUN off for a bit of wire wrapping playtime if all works out. [:)]

 

Is crazy glue gel electrically conductive at the digital logic level or is it an insulator?

 

edit: hot glue or epoxy?

Edited by Trash80toHP_Mini

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I actually just ordered one of those AUGAT connectors for the 74LS04 chips I have.  This way if we make progress with the SE/30 I can working wrapping the SE version.  Looking forward to seeing what happens by this weekend ;)

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Lots of homework to be done for that project before you start playing with the cool new toys! [;)]

 

68020 <-> 68030 - seemed straightforward enough for me to have at it

68020 <-> 68000 - not so sure about that one, you can color me clueless

 

One great thing about your SE hack: AFAIK the SE doesn't have a clue about Slot Manager and the Slot E conflict complications it brings to the SE/30. The SE PDS does its own thing and the video subsystem hasn't got a care in the world when it comes to its operation IIRC. But as I said, I'm pretty much clueless.

 

If you wanna take a stab at it I'd suggest starting up a dedicated thread. Folks will jump in to help you out on that project. I've floated too many whack-doodle notions here, so my byline tends to get ignored. :mellow:

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Clueless here about digital design as well, so I've been asking around for help in getting a handle on it. This came up in the discussion. Don't claim to understand it, but I can draw pretty pictures about it. ::)

 

74LS04-Polarity.jpg.3ce47e68996c2832078ff1909b29ba2d.jpg

 

This way the shorted line for direct, non-inverted connection is on the input side of the inverter. Having it on the output side might be a problem? Is the 04 output tri-stated to give a null connection on output side with no input? Also unsure which PDS gets hooked up to the inverter input, guessing the LC PDS as in the bottom half of my diagram?

 

Bildschirmfoto 2019-04-28 um 11.52.26.png

 

Totally confuzzled here and I probably got  the diagram all wrong too. :mellow:

 

Edited by Trash80toHP_Mini

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