How to get 16x16 RGB P10 1/4 scan panel to work with arduino

Hello and thanks for all your work

I have a 16x16 RGB P10 1/4 scan panel

I'm getting some success using the modified Adafruit RGB Matrix Panel library (from here), to work with 1/4 scan panels

With the modified version of the library and scrolltext_16x32 example, I can print a static "P" (also "L"), using

const char str[] PROGMEM = "P"; //"L"

void setup() {
  matrix.setTextWrap(false); // Allow text to run off right edge
void loop() {


  matrix.setTextColor(matrix.Color333(210, 210, 210));
  matrix.setCursor(16, 0);

But it display as at the image P. For the upper part of the letter, (16,0) pixel seems to be at pixel (16,4). And For the lower part, (16,4) pixel seems to be at pixel (23,0) and sort of mirrored (best appreciated with other letters, image L)

At first I tried changing matrix size at RGBmatrixPanel.cpp, but surrender and just used the library as is, printing at pixel (16,0), with this results

Can somebody give some guide on what should I change to get this 1/4 scan 16x16 RGB P10 panel to work as spected. This Meaning printing a letter at (0,0) and getting it at upper left corner of the screen ?

Also changing the width of the screen from 32 to 16 ?

Please any help is appreciated


Seems no images allowed so: L.jpg -> P.jpg ->