MEM11 Status Update

Noel Chiappa jnc at
Thu Jan 22 07:04:18 CST 2015

    > From: Guy Sotomayor

    > the way that it works is that 144 bits will be shifted out and then 
    > all latched at once.

Ah. That will limit the rate at which you can update the lights, though,
right? I mean, you won't (be able to) update the panel after every word, will

Although I suppose even if you only do it after each transfer, that's
probably still going to give much the same visual effect.

    > Will you be grouping them in 3's, with slightly larger gaps between
    > each group of 3? That would really maximize the ability to look just
    > like the old RF11 display panel.

    > No, it'll be just like the DEC panels. All of the LEDs (in this case)
    > will be evenly spaced. The overlay masked the bulbs that weren't used.

Ah, I was faked out by the illustration (not a picture, alas!) in the RF11
manual, it looked like they were grouped.

I wasn't sure if the larger spaces between various fields were just bulbs
they didn't wire up, or if they were also masked by the overlay; I just
looked at some of my KA-11 overlays (now _there's_ a machine with blinking
lights! :-), and they are indeed blanked in the overlay, so I would
guess/asssume they did the same on the RF11.

    > From: Bob Rosenbloom

    > I have an indicator panel that's labeled "Peripheral Indicator Panel
    > 5406458A"
    > No overlays or anything to indicate what it was used for. Is it
    > possibly the disk indicator panel?

That sure looks like it. Too bad you don't have the overlay...

Now that I think about it, I wonder if that panel was originally used on the
KA? The 36 bits are certainly suggestive... I'll have to see if I can find a
picture of the disk/tape controller display panel from the KA and see if that
could have been it.


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