CFD435AQP9 S-PWM Panel

[Chowdish]

I've recently acquired some matrix displays. and the library is kinda working.

However, my display has r3, g3, b3. And the driver is not showing these correctly. just dead leds.

I know this display is not officially supported. but i thought i might give it a shot anyways.

The chips on the display is:

RUC7258D

CFD435AQP9

Some images:

[mrcodetastic]

The 'CFD435AQP9' is a 'PWM' chipset that means these panels operate differently and not compatible/related to this library.

There are many variations of these types of panels and unlike the panels this library drives which are essentially just a long chain of 'dumb' shift registers, the chips on this panel are basically a framebuffer that take pixel data and then computes the PWM output frequency.

I was given a bunch of similar eWaste panels and spent weeks trying to reverse engineer how it worked with varied success. Note: This was a different PWM chipset, not the CFD435AQP9.

https://github.com/mrcodetastic/ESP32S3-MBI5153-DMG1075-DMA

Somebody else wrote a custom library based on this libarary for yet another chipset:

#324

CFD435AQP9 sounds new, so you'll need to write your own code after reading the datasheet.

[mrcodetastic]

I would be interested to see video of how it operates with this library as I would have expected garbled output only. Only by luck I would have thought it would show anything at all.

[Chowdish]

I would be interested to see video of how it operates with this library as I would have expected garbled output only. Only by luck I would have thought it would show anything at all.

I’ll try this library later, and send some videos of it.

And thanks for the help btw, i appreciate it.

[mrcodetastic]

If your in Europe or the UK and have a lot of these panels then feel free to shoot me one and if i get bored id love to reverse engineer

[Chowdish]

I'm in Denmark, so i might.

How would you use the library you mentioned above?

[board707]

However, my display has r3, g3, b3.

Hi
What is panel's dimensions in pixels?

[Chowdish]

However, my display has r3, g3, b3.

Hi What is panel's dimensions in pixels?

I believe its 98x110

[board707]

its 98x110

How it can be? If it has a three RGB channels - the height must be a factor of three, isn't it?

[Chowdish]

its 98x110

How it can be? If it has a three RGB channels - the height must be a factor of three, isn't it?

I counted wrong, its 96x110

[board707]

its 96x110

Which of digits a height and width here?
Could you please provide a clear photo of the entire panel from the rear?

[Chowdish]

its 96x110

Which of digits a height and width here? Could you please provide a clear photo of the entire panel from the rear?

686ECC6E-14FC-4FD3-BEFF-D1227CD8B826.mp4

[board707]

Thank you
Unfortunately, I can't see the video.
On the photo it looks like 96 width X 110 height panel.
Because there is only one connection socket, it seems that the panel doesn't support chaining.

[Chowdish]

Thank you Unfortunately, I can't see the video. On the photo it looks like 96 width X 110 height panel. Because there is only one connection socket, it seems that the panel doesn't support chaining.

I have no idea if it is chainable.

The video is just showing the output from the library.

Do you have any idea how i could get this working? Or explain why there is 3 rgb channels?

[board707]

The main problem is the driver. As mentioned @mrcodetastic above:

The 'CFD435AQP9' is a 'PWM' chipset that means these panels operate differently and not compatible/related to this library.

In addition with 3 RGB channels and, assumedly, without ability to chaining, it seems to much efforts to make this panel works with the library.

[mrcodetastic]

This conversation is repeating itself. I noted it's a SPWM panel which has nothing to do with this library.

Please refer to a discussion topic on S-PWM panels.

You're going to have to read the data sheet on the SPWM chip and reverse engineer through trial and error. I tried to create code for some other garbage SPWM panels I was given, and it was a right pain in the ass.

Search across GitHub to see if somebody hasn't already written code for this chip.

[Chowdish]

Cant find anything with this exact chip.

But i can get some output on the display, so something in this library is working, scrambled, but working none the less.

So you guys think its a lost cause? I dont have the knowledge to reverse engineer this, im just an electrician.

Ive got 15 of these panels though 🥲

[board707]

If you have 15 panels, how do you plan to use them if it not support chaining?

[Chowdish]

I have no idea, but something tells me they do.

https://www.fabuluxled.com/thinpad-series_p20.html

Im pretty sure this is the product it came from, it uses “Thinpad” in the name. And it looks similar, so maybe.

[mrcodetastic]

Cant find anything with this exact chip.

But i can get some output on the display, so something in this library is working, scrambled, but working none the less.

It's because the library is sending binary to the chips on this panel, but it's completely in the wrong format so it's garbage. I'm amazed it's actually showing anything at all.

So you guys think its a lost cause? I dont have the knowledge to reverse engineer this, im just an electrician.

Pretty much. I can't find a dataset online about this chip so it'll be difficult to write any code for it.... BUT it might be luck work in a similar manner to some other panels I worked with.

Ive got 15 of these panels though 🥲

I'll send you some dkk and you post one my way? Absolutely no guarantees I will have time or be able to figure out how it works, but if I get bored will try out of curiosity.

You can only drive ONE panel for each esp32 with these panels. No chaining possible.

[mrcodetastic]

Continuing conversation here @Chowdish