Im messing with panels i purchased on aliexpress which turned out to be a qiangli branded panel
and despite messing with it until i tried this library i was unable to get any output to the board.
Now By using –led-panel-type=6126A or =6127 I’m getting flashes of white bars every 2 rows, i can change this to rows of 1 bar, a single row, or 3 rows, but I’m unable to get any further, as after that the panel doesn’t even give me a colored input to show where I went wrong, does anyone have any ideas what i’m doing wrong?
Thank you, you’re right, I’m blind.
In that case, you don’t need any additional settings for the DP3246 driver.
You only need to set the multiplex type to 5 for the second chip (DP32020).
No worries! im not going to lie i read it as 64 the first time i checked the library too and had to do a double take
im wondering if the board does require some extra setup then, since this is the exact command im using:
sudo examples-api-use/demo -D1 --led-rows=64 --led-cols=128 --led-brightness=80 --led-row-addr-type=5 --led-slowdown-gpio=4 and still dont get anything other than a black screen, even when providing 5v at a max of 10A, whereas the 6126 command is the only way i actually got anything, even though it was a flash of white bars. is there a chance the 3246 has a special startup condition? one that somewhat overlaps with the 6126 or 6127?
no worries! I’m trying to contact the manufacturer but it seems like they aren’t great at responding, let me see if i can find any datasheets myself, since the seller was unable to provide one, it would be good to know for both Libs, since we can say this was tested
Yes, I also found a link to the Chinese description and judging by the first glance, this driver really does require pre-configuration similar to FM6126.
However, the datasheet alone is not enough to write code for the driver; tests on a real panel are also needed.
I’m not sure how exactly to write the pre-configuration nor do i know how long it will take, basically using this for a school project and need to work with what i have
based on what i could gather the 3246 treats latch as a command signal, based on how long latch is high for it either writes to either register, signifies end of row / frame, or latches display data
Gladly willing to offer one or all of my panels as a test subject though! and willing to do what i can if you’re able to push me in the right direction of where to start, i don’t mind doing the work, its more I’m not sure what work needs to be done to write the driver
Yes, this is a standard configuration loading scheme for such drivers.
Thanks, but I think shipping will be very expensive. What country are you from?
I’m happy to help, but I’m afraid writing a driver isn’t the fastest way to implement your project The easiest way is to sell these panels and find others with a compatible driver.
Not sure if it will be possible to sell or return them since i ordered them over a few months ago
how long would writing a driver take? even if i had to do the tests where i am with some guidance
Im in canada at the moment, not sure how much shipping would be, and i only have a month and a half in time anyways (to be done safely)
if i did have to sell and return these where would i be able to get 128x64 boards that i could replace them with? and be able to be sure they are the correct type so i know they work when they arrive
if the driver is possible to write within that time frame i don’t mind giving it a shot, if its similar to other drivers that have been implemented wouldn’t it be less of a full re-write and editing one of the others?
I think it’s logical that if the driver is similar to those already supported in the project, adding it will be easier. But to do that, you’ll need to understand the project code and the driver’s protocol, which will also take time.
Unfortunately, I don’t know the details of 6126 driver support in HZeller libray, as I’m not the author of this project.
Could you tell me more about your project? How many panels are used? What’s the main controller?
That i do get, i assume half the time will just be reverse engineering, even will artificial help it likely wont be easy, unless the other drivers use the same methods with different timings
The basic concept is a dnd map display, essentialy 20 panels lain out flat in rows of 5
we were planning to use an FPGA originally, but since it has this wierd startup, it fell to me to figure out, so i’d just use this library on a rpi 4 in 2 chains of 10, or two rpi 4’s with 2 chains of 5
I did see the DMD project, How different would that be in terms of just displaying an image or gif? would writing a driver there be easier?
You can run about 30k pixels per rPi channel with 7bpp color depth before the total refresh rate drops too much for the full display not to be that useful anymore.
So my biggest display is 384x256 (100k pixels across 3 channels)
You don’t need to build the hardware to test this, you can simply run the demo code with show fps, and adjust the parameters to output to the size you’d like and see the resulting fps output on the command line.
The easiest way is to sell these panels and find others with a compatible driver.