SDG2042X signal generator; screen brightness

[xpsion]

Hello,

I am suffering with a very stupid trivial issue.
Years ago i reduced the screen brigthness of the SDG2042X display uing a certain key combination that is not mentioned anywhere in the manuals.

Since then, my eyes have aged and i need more brightness to read the info....
But I can't remember what the key combination (its the rotary knob after a key press but .....
Tried all of it but, an feel stupid to not get it set....

I would really appreciate some help on it!

Alex

[tautech]

Welcome to the forum.

Maybe you read about it where most things SDG2042X are:
https://www.eevblog.com/forum/testgear/the-siglent-sdg2042x-thread/

A quick look through my resources didn't reveal anything however I do remember something about this a few years back and later when I get time I'll do a deeper forum search for the answer.

[tautech]

Not found on forum yet but checked the Help files in our SDG6202X and reset to Factory Default might do the trick.
Utility/System is where you can find Default.

[xpsion]

Hi,

No the factory reset does not change back the brightness......

[tautech]

No the factory reset does not change back the brightness......

I have sent your query to Siglent Tech support.

Does changing the UI style help ?
You can find this in Utility>System>P2 UI Style = Classical or Normal

[xpsion]

Hi

changing the UI from classic to normal, change the channel color but intensity stays the same, i think it is at ca. 60% of its max.

I am sure there was a procudure of pushing 2 buttons simultanious and then there came a  brightness level nr between 0 and 10 (or 5 or 7 levels , i am not sure) that could be set by the turn knob for a brief moment, then the screen went back into normal operating mode.
I am trying everything,..... drives me crazy that i can't recall how i did it.

Alex

[tautech]

Hi

changing the UI from classic to normal, change the channel color but intensity stays the same, i think it is at ca. 60% of its max.

I am sure there was a procudure of pushing 2 buttons simultanious and then there came a  brightness level nr between 0 and 10 (or 5 or 7 levels , i am not sure) that could be set by the turn knob for a brief moment, then the screen went back into normal operating mode.
I am trying everything,..... drives me crazy that i can't recall how i did it.

Alex

It must be some undocumented mechanism as the current staff at Siglent do not know about it and only offer the LED backlight brightness may have aged/dimmed.
Hopefully someone can come to your rescue.

[xpsion]

  ahhh....

Well that leaves 2 options:

1. open up the unit,locate the pinout of the PWM signal from the ARM processor to the backlight
lookup the register address and ask somebody who can read the firmware if they can trace back this address in the firmware to find out the key/s ....

2. Make a ~30.000 key press table with all the combinations, press order etc  until i find it back

The display is not aged at all, due to the low brightness setting, it has been saved for aging .. it's only 6 years old and its a fine piece of equipment.

Thanks for checking out at Siglent, i tried also here in EU but they even don;t reponse at all: no idea i guess
Can they not get a hold on the  chinese engineer/software guy of the unit that wrote it ?? ))))

[tv84]

Do a 3rd option which should be an interesting project:

- emulate the keyboard interface and test all the sequences until you get your (supposed) brightness scale.

[xpsion]

Hi HP,

Well, i clearly remember it was somewhat difficult to enter as you need to push several keys at once, you needed to hold the unit firmly else you pushed it backwards. What i remember is that it involves the oressing of 1 or boht arrow keys to gether with another one and before that the + or the dot key.
But in which part of the menu or how ?? i may have the wrong keys in mind...

The point is that i don;t know how to use the programming instructions for a phyton script (using the virtual key fucntion) to give an instruction of simultanious key presses .....

One other thing that I remember is that I found it not searching for SDG2042X but using  SDG2082X  or SDG2122X  (or SDG1062X or SDG1032X)....
It was by following several links from a certain blog, I assume it has been the EEVblog as there is not really another one that is well indexed by search enginie (it has been Google). All history of that time (12/2016 ~ 4/2017) data is gone...

Do you have a clue how to simulate multiple key presses at once ?

Alex




 

[tv84]

The only thing that comes to mind would be to XOR the values of 2 keys (3 or whatever). Or OR the values, or AND.

As such, you could try to send all the 256 combinations as <value>.

If this theory is correct, then the number of combinations of consecutive presses can be much lower than previously thought...

Just an idea...

[bdunham7]

Have you updated the firmware since you made the adjustment?  Possibly the brightness adjustment function simply doesn't exist in newer firmware.

[xpsion]

my model had calibration document dated dec 6th 2016  so it was V2.01.01.17R5  , and that is the one i use now to eliminate that option

[tv84]

Thinking loud about this...

Doesn't the key+LCD board contain a controller? If so, the key combination could be intersected within this board and never reach the mainboard (as long as it had some graphics overlay feature...).

[xpsion]

Aha ! ,that could explain the weird key combination, as the normal cpu board does not use  multiple key commands....
Do you know which type of controller this is ?
Then i could investigate its pwm output.
I assume the main board just gives a base command to this controller to switch on the backlight, and then a pwm output on this controller is modulating the brightness level of the backlight.

[tv84]

Do you know which type of controller this is ?

Nope. Maybe looking at the FW something can be found... Don't know if it's already on the forum.