New bug? M Clock LED blinking dimly under certain conditions

[Hlaalu]

Hi there,

Last week I got a NS3 88. This is my first high-end keyboard, so I am still getting acquainted. So far I am loving it.

There is something I noticed that I don't understand and I can't seem to find it on the manual nor anywhere on the internet.

Under certain predefined programs, the red LED of the Master Clock key blinks dimly -- to see it, you may have to switch off your ambient lights. Please note that the LED isn't broken, as the key works perfectly for what it's supposed to do.

For example (for any of you who still happens to have the original Nord programs loaded in), try retrieve these programs: A15, A25, A45, A55, B25... These are just the first ones I could find, but I am sure there is more.

Now, stay on Panel A and look at the Master Clock LED... mine blinks dimly.

What's the function of this?

Thank you folks

[Hlaalu]

Hasn't anyone tried to replicate this on his NS3?
Thanks

[dmamfmgm]

I read your post yesterday and it seemed like a good, solid description, something I could investigate when I had the time.

But now I'm away from my Nord all week. Thus I haven't had a chance to try to repro what you're seeing.

[pterm]

Older Nords use "multiplexed LED matrix" to control LEDs. This places LEDs between the intersections of two control signals rather than just controlling the LED from a single control signal. I expect the NS3 still uses this matrix technique.
This means that LEDs share control signals, so it becomes possible that an LED might turn on slightly if there is a timing error in the control signals or if there is a circuit error in the hardware.

If I recall correctly, diode-based matrix control circuits do not normally exhibit leakage. That is, the LEDs ought to only illuminate when commanded to do so if the circuit is properly designed an the control signals are error-free.

If other users see the same behaviour you described, it indicates a design error either in software or hardware by Nord (seems unlikely to me). If others do not see this, I think it indicates a hardware error on your NS3 (I suspect a short circuit between control signals or a damaged component).

I suspect this dim blinking of the is unintentional rather than functional.

[dmamfmgm]

Yes, the electrical engineering term is "Charlieplexing"

[FZiegler]

Hi Hlaalu,

my brand new NS3C (well, don't know when it was produced) doesn't have it.

I just tried the programs you mentioned, and am not shure if there haven't been any changes in the fabric programs by Nord - but besides that ... I haven't changed anything yet. One program has the "mst clk" led lit, the others off, but none is blinking.

No idea what this means for you.

[pterm]

Yes, the electrical engineering term is "Charlieplexing"

I hadn't heard of this. Thanks!
I see the Nord E2 used traditional multiplexing on the Electro 2: http://www.workhousepoets.com/NE2%20Ser ... matics.pdf. --The "Charlieplexing" uses fewer pins.

[Hlaalu]

If other users see the same behaviour you described, it indicates a design error either in software or hardware by Nord (seems unlikely to me). If others do not see this, I think it indicates a hardware error on your NS3 (I suspect a short circuit between control signals or a damaged component).

Thanks for posting. LEDs and circuitry are definitely out of my area of expertise, so I can't really comment back, but I wonder if that was an hardware fault, whether the LED would still work normally when you press the button and adjust the Master Clock. Mine does work normally in this case, and that the LED's blinking speed matches the currently selected tempo.

It would be nice if any of you was able to replicate this.

In the meantime, I discovered two other things:

1) For some reason, this only happens to programs numbered "something-5". Not on all of them, but it's always the Panel A of programs 15, 25, 35, 45, 55, and so on, with one occasionally missing. I checked up to bank F, and it's always on number 5.

2) I tried copying the program to an empty slot, other than -5 --> blinking is gone. This is interesting...

It would seem as if "something" on programs "-5" is "wrong"?

By the way I am going to make a short video of the issue and upload it here...

[FZiegler]

I think that in any case you should get in touch with your dealer (and maybe Nord). If the problems increase in the future, they might say: You should have told before. Even if, at the moment, they say: It's nothing, all's fine.

What you describe now sounds like a software issue (every -5 program), but who knows.

[Hlaalu]

Sure enough if it turns out that I am the only one to have it, I will definitely report it to the dealer and possibly to Nord.

But that's why I was curious about other people's feedback. Apart from you (who tried on the Compact version), hasn't anyone else here tried to reproduce this on their 88? It literally takes less than one minute to check.