Issue with 64x64 panel based on DP5125D and DP32020A

[mzashh]

i got a new HUB75 Panel today and it does not seem to work properly with the library. The panel initializes fine and seems to display stuff but everything is mapped incorrectly and overlapping. the panel seemed to work more or less the same with different driver types, but it flickered with some the best one i found which worked is MBI5124 and I am using the same one in the below pictures.

also the panel is labelled as a QiangLi Q3

Here is the SimpleTestShapes demo (64x64)

and here is the Plasma demo (64x64)

plasma.mp4

So i there any way I can drive this panel properly?

[davemaster]

Can You share a picture of your connections? E_pin present? Thanks in advance

[mzashh]

Can You share a picture of your connections? E_pin present? Thanks in advance

like my other 64x64 hub75 panel (which works fine cuz different driver) the E and D pins are either labelled as GND or NC and yes i have connected those and defined them in my code. i did a continuity test on them and D which is labelled as NC is not grounded while as E is grounded so either the input is ABC or ABCD, no E pin

[board707]

I think, the problem is in the fact that DP32020A is a shift register miltiplexor - do you know how to work with it?
By the way - what is the scan factor of the panel?

so either the input is ABC or ABCD, no E pin

sure, a three pins is enough for shift register

[mzashh]

I think, the problem is in the fact that DP32020A is a shift register miltiplexor - do you know how to work with it? By the way - what is the scan factor of the panel?

i am not sure how to work with it, the scan rate isn't mentioned either on the panel or where i bought it from but since the E pin is pretty much shorted to ground and D is no continuity to ground it is either a 1/16 or a 1/8 scan panel, pretty sure about 1/8 scan. i tried my code which works with my 32x32 1/8 scan panel but that does not work either. so it maybe a 1/8 scan but its wired pretty weirdly

i found this library https://github.com/ironsheep/P2-HUB75-LED-Matrix-Driver though it uses some proprietary hardware but it has support for DP5125D and states that the address is only ABC so 1/8 scan ig

[board707]

since the E pin is pretty much shorted to ground and D is no continuity to ground it is either a 1/16 or a 1/8 scan panel, pretty sure about 1/8 scan.

As panel uses a shift register multiplexer, the number of ABC lines means nothing about scans. Please show a clear photo pf panel rear side

i found this library ... it has support for DP5125D

The DP5125 is a standard driver, you don't need a special library for it. The current library is definitely supports this driver.

[mzashh]

Please show a clear photo pf panel rear side.

[board707]

According to number of chips, the panel is 1/32scans

[mzashh]

According to number of chips, the panel is 1/32scans

1/32 scan but no D and E pin man this is one weird panel, so any ideas on how to drive it?

[board707]

1/32 scan but no D and E pin man this is one weird panel

Again, DP32020 is a shift register, it don't need more than ABC to control 32 scans.
Read this, the part titled "HX6158" - it is an explanation how the SR multiplexors works.

[board707]

this is one weird panel, so any ideas on how to drive it?

There is nothing weird about this panel. The 5125 driver is very common; some settings are needed only for the 32020 multiplexer. As far as I remember, @mrcodetastic had code for panels with such multiplexers.
Now I need to get busy, a little later in the day I will find links in the "Issues" on such panels

[board707]

The code to work with shift register multiplexors discussed in #164, #429 and some other issues.
(Correction) - the advice from #164 probably won't work with 32020 chip.

@mzashh Do you have an experience to use this library with a "standard" 1/32 panel? If so, I will show what to change in the code to work with your panel.

[mzashh]

thanks for the help @board707 but seller has offered to replace my panel with a normal hub75e panel based on FM6124D + TC7262C driver, which i hope will work without any modifications. i have already packed my old panel for shipping it back so i cant really test stuff with it.

I will leave the issue open just in case someone else needs help with this type of panel in the future