Now *that* is a wonderfully obscure device. I wonder if any software for it exists anywhere. paul

On 12/5/21 3:24 PM, Ethan Dicks via cctalk wrote: A great lead-in to my story.? I was working away on the RK11 implementation in the QSIC and when I felt like taking a break but still wanted to get something done, I'd work on the indicator panel.? Of course, the indicator panel ended working before the RK11.? Just having 144 lights that I could assign to any purpose was useful but then came the day when the RK11 was mostly working.? I loaded up an RK11 exerciser program that Noel wrote and just sat back to bask in the glow of the blinking lights.? It was a good feeling. Then I noticed something that wasn't right.? Even though the exerciser was working, I saw a pattern in the lights that showed up a bug in my implementation.? I'd really only implemented the indicator panel because I thought it was fun but it lead me to a bug to fix right off. Here's a short video clip of the indicator panel in operation and showing that bug.? I'll leave this for a day or two (or until I remember again or someone asks) and then say what it is I saw.? I think anyone with a reasonable familiarity with the QBUS will be able to pick it out though I'll say that "Latched Address" is the address "half" of the data/Address Lines, that is the value of those signals when SYNC is asserted. http://pdp10.froghouse.org/qsic/ip-full.mp4 The inlays are mostly not done with any tools I have.? I do the graphics with Inkscape.? Rod made up the blanks with silk screening.? Then I have the white printing done at a printshop I found who has a large, flatbed printer that can print white ink.? I do have some ideas about how I might try to make up blanks with a laser etcher I have access to but at the moment we have an ample supply. Also, I've experimented with making my own bezels out of PVC board from Home Depot using a CNC router.? In the pictures below, the yellowed bezels are old DEC bezels while the white ones are ones I made.? I figured that if we ever get the QSIC shipping and people want indicator panels (I hope they'll want indicator panels), I'd rather not depend on them ripping apart old DEC bezels to make this work. Anyway, I'd be most happy to have another person with more tools to help build bits and pieces of this stuff.? I've noticed that as I gained access to different tools, I came up with different ideas about how to make things.? I didn't think the laser etcher was all that useful until I started using it.? Now I want to use it for everything.? Turns out it can't quite handle 3/8" Delrin; it just melts it and makes a mess.? Speaking of help, if anyone wants to review the QSIC design, I'd welcome that.? This is by far the most complex circuit board I've ever designed. Back to indicator panels, here's a picture showing a bit of the evolution of my indicator panels.? The video above shows it really early, when I just taped a paper inlay to the circuit boards.? Then the bottom panel in this picture is taping that paper inlay to an MDF light shield.? The top panel is using one of Rod's blanks with paper labels taped to it.? And then the third panel down is a printed inlay like we're talking about now for the RK11-C.? The second indicator panel is a TC08 inlay that I borrowed from Noel to use as a model as I worked on the graphics for our own. http://pdp10.froghouse.org/qsic/indicator-panel-stack.jpg Here's a close-up of the TC08 and our printed inlay.? I'm rather pleased with how it looks, I have to admit.? The only real thing I'd like to change is the gloss.? Somehow, DEC's inlay is as flat as flat can be.? There is no glare to it whatsoever while ours are quite glossy.? I've looked at frosted acrylic and it's a little better though really it just diffuses the glare, it doesn't eliminate it.? I've also tried some spray-on frosting which helps a little but it also has a tendency for its solvents to melt the printing that's already there so that's a bit fraught. http://pdp10.froghouse.org/qsic/indicator-panel-printed.jpg Dave

On 12/5/21 4:43 PM, Henk Gooijen via cctalk wrote: Fun.? That's a way to get some more lights into your life.? I like it. I think the only reason to have an RK11-C inlay is if you have an RK11-C.? Otherwise I can't see that it makes much sense. The one other place I might, maybe, possibly see one being used is along with one of our QSICs or USICs.? I could add an option to drive an RK11-C inlay if someone really thought that was what they wanted but the RK11-F inlay that we came up with really is a better match and more functional (which is why we came up with it) as well as supporting the RP11 implementation that I'm sure I'll get working any day now (snort). Dave

One dumb suggestion to make it easier to control 144 lamps is to use addressable LEDs.? You can control them in banks or all in a single serial line.? If you use a single line you can control all of them with just 1 GPIO. Each LED requires 24 bits of data.? That would be 3,456 bits.? The WS2812B has a 300uS low start indication and 1.25 uS per bit.? That would mean it would take. 4.62mS to update the all of the LEDs. Since these are tri-color LEDs you can control the color and simulate incandescent lamps (Simh and the PiDP-8/i do this with LED PWM via an x/y matrix). Another advantage to the LEDs is once they are set, you don't have to talk to them again until you need to change something. I am going to use a Raspberry Pi Pico RP2040 CPU's PIO co-processor to drive the LEDS from a 432 byte array in memory.? All I do is update which LEDs I want to change and the PIO DMAs the entire array to the LED chain once every 10mS (or slower depending on need). On 12/6/2021 9:13 AM, Henk Gooijen via cctalk wrote:

One of my zillions of projects is to redesign Oscar Vermilion's PdDP-8/I using the Raspberry Pi Pico board and these LEDs. I would use one core for SIMH (the PDP-8 simulator) and one core for the Incandescent Emulation. Right now I'm too busy finding parts for my real PDP-8/E and getting it running. Think of the addressable LEDs and LEDs with the shift register built in ?. When you are ready for a redesign, you might consider it for a cost reduction. If I may8 ask a question.? I have never had boards made before. How do I find a good board house that is reasonable and how do I specify the board especially for the PDP-8 Omnibus which should have gold fingers on the edge connectors? Thanks and good luck, ????????????????? Mike On 12/6/2021 2:07 PM, David Bridgham via cctalk wrote:

For other boards without gold fingers where would you recommend and how expensive for omnibus size boards? On 12/6/2021 5:07 PM, Guy Sotomayor via cctalk wrote:

Board cost depends on quantity, the more you have made, the lower the per board cost. PCBCart.com charges a "tooling" charge for a new design.? They do look over the designs carefully and reorders don't incur that charge. To get an idea, I had a run of Joerg Hoppe's DEC Flip-Chip Extender Hex +5 boards made (http://retrocmp.com/tools/dec-flip-chip-extenders) I had 20 made.? My total (board cost, share of tooling, share of shipping and share of customs at that time) per board cost is $42.60 (I'm selling them for $42 as I didn't get the customs charge until later). On 12/6/2021 7:21 PM, Guy Sotomayor via cctalk wrote:

Thank you. On 12/6/2021 6:33 PM, Jon Elson via cctalk wrote:

I?ve had good experiences lately with both pcbway and jlpcb.

On 12/6/21 17:45, Mike Katz wrote: I was planning to try PCBWay for my boards. They say they do hard gold fingers and they have a board assembly option that looks like it can do what I need. I haven't used them before so this will be an experiment in that direction as well. If you're using KiCad for your designs (and if the Omnibus uses the standard DEC boards), I have templates for double and quad height? boards that you're welcome to. Since I haven't yet made boards from them, check yourself that they're right before ordering but at least they'd be a start. Dave

I've used PCBCart.com to have thousands of boards produced. Mostly with gold fingers They've done a good job with the boards, though they're mostly two-layer and not overly complicated. You just tell them how many gold fingers you want (and if you get it wrong, their design check will clarify with you). You also can specify if you want a chamfer on the edge and the degree of that chamfer Things weren't good when the tariffs were in effect and the shippers didn't understand what the PCB tariffs applied to and what they didn't.? That added a lot to the cost. That's back to normal now but prices are up (like everything else). Todd On 12/6/2021 5:45 PM, Mike Katz via cctalk wrote:

Raspberry Pico PIO engines are seriously cool. I used them to implement DDCMP synchronous line protocol in a small USB device wrapped around one of those devices. That includes the "integral mode" modulate/clock recovery/demodulate functions. Something I haven't tried but appears possible: 10 Mb/s Ethernet using the PIO. At least full duplex, and perhaps even half duplex. Not a whole lot of point in that, I suppose. paul

Ethan, I completely agree with reducing the strip size. One of my projects is a redesign of Oscar Vermilion's PiDP-8/I using addressable LEDs.? I was thinking of breaking the 88 LEDs into separate strands based on function (step counter & Multiplier Quotient [17 LEDs], accumulator and link [13 LEDs], Memory Buffer [12 LEDs], Memory Address [12 LEDs], Data & Instruction Fields and Program Counter [18 bits], Instruction & States [17 :LEDs]).? That would require 6 GPIOs. I don't know if the PIO can handle 6 separate GPIOs like that but it's worth a try. ?????????? Mike On 12/6/2021 3:05 PM, Ethan Dicks wrote:

On 2021-12-06 8:13 a.m., Henk Gooijen via cctalk wrote: USB yuck, is what comes to mind. Other than that the project looks good. I just built a prototype front panel, with 5 mm white leds, @ 4.5 ma each and they are really bright. You want diffused leds or a filter because you can see the phosphor when the leds are off. CMOS 20v10's drive the leds and read the keyboard switches. load switches, the shift in display data, and read switch data out. Display led data for bit of time a repeat. 10 inches long and 5 inches high card size. I have been using 16 meg SD cards (standard size) to emulate RK05 style drives for home brew 20 bit cpu (DE1 ALTERA), but your drives would make much more impressive system. 5 2901's are planned for the cpu card, and the control card has about 12 MSI TTL, 2 512x8 proms and 4 20v10's. 10 inches x 6 form factor and S-100 bus connectors. This leads me to believe that a PDP-11 could be built also at 60% scale using PDP-11 parts or 2901's. I would like to see that, rather than some PI version. Ben. PS: How much would a RK05 replica sell for?