Scrolling Text & 2D Matrix setup

I all, struggling to make sense of Scrolling Text which in turn is making me doubt if I have the matixes setup correctly in the first instance.

Currently I have two panels each on thier own GPIO.


(as a new user I’m limited to one picture per post so there will be multiple posts)

I have a Gap file to elimate the dead pixel (top and bottom) as the led string weaves around. I have both manually created the matixes and used the generator.

The text is sort of readable but then if you look closely the letters are back to front. In this shot we should see “Ayles” look at the y and e…


As an aside and this might reveal my lack of knowledge but whats the meaning of the eye & clock?



There is not really a meaning, It’s more like stopping the animation, if a clock show’s up: Animation is running, Eye: Animation stopped
(Basically Freeze the animation)

Seems your LED string seems a little unequal to the desired parameters

Enera thanks for the tips re clock/eye.

I,m getting myself in a muddle with the matrix. Physically it is a string of 254 leds with 2.5cm spacing.
The string starts bottom left and goes up 14 LEDs then one LED is to be wasted as it spans the gap horizontally and starts back down…

The Grey LEDs need to be skipped and ideally turned off.

The matrix size I have used is 15H x 17W and used a gap file as follows…


The trouble is when scrolling text is that it bounces up and down one pixel as it scrolls. In the picture below I have frozen the time display, look at the : in the middle and see its stepped.

The matrix is really 14x17.

Is there a way I can skip every 15th LED in the physical string?

You will need to set up ledmap. Gap file works only if every LED is included within matrix. You have LEDs outside of the matrix.

Thanks blazoncek, I had been playing with that but its sooo easy to make a typo and none of my attempts have worked.

To simplify it a little in my head I have dropped the concept of 2D maps and just configured a single string of 254 LEDs. Then I have applied this ledmap…
but this is the result.

I was expecting the LED with the circle around it to be the first one thats not lit.

Just in case its relvent I’m using v0.14.0

When you use ledmap the panel orientation (or number of panels) is meaningless.
You must map each and every LED participating in a matrix by visually placing each LED index (ID) into appropriate matrix X and Y coordinates.

I.e. the LED circled in red above does not belong into ledmap file. Your first entry in a ledmap should be 14 as that is the index (ID) of the first LED in the top-left corner.

I found this for reference.

I’m just not getting it. In my simple senario… I have a string of 30 LEDs and want to map out (-1) every 15th LED. This is my ledmap.json

but this is what I see

If I change the map…
Then the pixels I expect to be missing are. What am missing?

Needless to say the next step, implementing the matrix its all messed up.

Not clear on aim and also not sure if you have a string of fixed address or not but in this picture why did you add -1 and still kept 14 , what i would do is 13,-1,15 ( if you want 14 to be off ) else try to just remove 14 from the map so …13, 15 …

Both incorrect. There is no need to add -1 if the LED is not included in the matrix. Just do not enter it into ledmap file.

 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,

I said “visually place index into matrix layout”.

There you go all me as you knew. Just could not get my head around it.

Got one panel working.
LED string of 255 LEDs, every 15th skipped. With this ledmap.json
Then configured a 2D matrix with 17W x 14H matrix.


Now have to do this for an additional 3 panels each on its own GPIO in a 4W x 1H config.

Thanks all

Not true , 13,-1,15 will make 14 off

Simple when you know how :grinning:

Very good for you , looks great

Its that time of the year, prep for a Crimbo project. Once complete I’ll post a pic or too.

Cool , can you also with that post the source of the strip you are using