Multiple P10 1/4 scan LED display boards

I hope this is the rightplace on the new forum to ask advice on LED P10 modules.
I have recently got into using P10 multiplexed LED modules.
My first project used single colour red Leds to display on a 32 x 32 LED panel ( made up of two 16x32 panels stuck together.)
While I had played with the DMD library, this project needed a celphone/wifi update function, so I used the HDW00 controller module and it works fine.

My next project has 8 full colour modules, 1/4 scan, with HUB75 sockets.

I it is a copy of a previous board I made which had 24 daisy chained 7 segment displays with TPIC6B595 shift register / drivers.
I would like to be able to use my existing decoding sketch that has an array of 24 characters to send to the panels.
Of course some of the actual numbers are grouped into 3 or 4 for the new display modules, so I only need 8 panels.
I have searched around and found some posts such as:-
(P10 32x16 LED panel 1/4 scan now works with Adafruit_GFX)
but reading the Adafruit description and it says that their library is pushing it to drive just one panel with full colour with an arduino memory.
I can understand that as these displays have to be constantly refreshed ( unlike my previous latched 7 segment ones that were " light and forget " ) that memory will be precious.
However, I only have 6 yellow numbers (0-9), 12 green numbers, and 6 red numbers.
I need no animation, or large font tables, or dimming, and I really wish I had bought single colour panels which I could have driven easily with the DMD library.
There are other HD controller modules with 1/4 scan HUB75 connectors, with usb drive, but I will still need the Arduino to feed the array to it, and I have no idea of the format.
Is there a library I could use with just connecting the one colour, and sorting out the 1/4scan driving sequence ?
I might have to use say 4 promini modules to split the workload ?
Any ideas?

I am still battling with this module, but have mapped the snake route through the panel, and have also found that the Output Enable, and the address row lines are all active low, and the R1R2G1G2gB1 and B2 are active high.
The address rows are not binary encoded, but the nA nB nC and nD are the direct drive of the upper and lower pairs of rows .
I just need to show 3 static numbers on my display, and cannot figure out how to change any of the libraries to suit my displays.
I could even just have images for 0-9 if I can get the display order right.

P10 modules are high brightness modules. This means they reduce the multiplexing which results in higher average current. This would lower the number of pixels per panel, so to compensate for this they increase the chain length internally. In order for the PCB trace stuff to work they use a goofy pattern. Generally speaking the 1/4, 1/2, etc multiplex panels use direct drive and not a 74HC138 decoder.

P10 and/or outdoor modules are known to do this. These are to be used in daylight or far away. P10 stands for 10 meters if I am not mistaken. Naturally these panels use more power and can have less load frequency due to reduced multiplexing.

The Arduino will work with these about as good as it would with any constant current HUB75 based LED Matrix. What you will need is a pixel mapper and rework the multiplexing logic. Other than that it should work just fine.

Arduino Pro has limited memory, however you are correct using multiple Pro Mini's will likely work. 2 panels should be possible. This would likely support a double buffering and1 bit color or single buffer with 2 bit color. You could look into SmartMatrix (aka PixelMatrix). With the Arduino you would likely need to write your own or port it. Raspberry Pi library may have supports for most of this.

If looking to avoid coding yourself look into SmartMatrix or Pi solution. I do not know what you plan to do in the application software. I do not know what kind of quality or reliability needs you have.

Thanks, yes it is the remapping of any library that is stumping me, I cannot see the sequence in the library files.
The P10 refers to the pitch of the LEDs being 10mm apart )

We are both right. LED Viewing Distance (

rpi-rgb-led-matrix/ at master · hzeller/rpi-rgb-led-matrix (

SmartMatrix/MatrixPanelMaps.cpp at master · pixelmatix/SmartMatrix (

I manage make my own mapping for this, if I needed 4 digits across the panel would be easy as each digit would have column + 16 for the same pattern.
I needed 3 digits across, so had to make 3 separate 0-9 maps to cater for the zigzags, but I got it all on a 328 pro-mini ..

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