RGBMatirxPanel that gives half text another color

I have put up my RGB Led Matrix Display 64 x 32 pixels with a particle photon and i have also a sd card reader to it so i have got to configure the display like the RGB shield V4 configuration and then when i start to show some text on the display i getting half text in another color, see picture:

I can not understand why? If i put all cables and pins like the the old configuration in examples i get it to work fine.

The display cable to photon is connected like:

A A0
B A1
C A2
R1 D0
G1 D1
B1 D2
R2 D3
G2 D4
B2 D5

Any idea?

Make sure your power supply is beefy enough to handle this many pixels at once. I’ve had some issues when I used an underpowered supply and was pushing it.

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If i using pins like RGBSHIELDVERSION is 3 then i get all to work but if i change RGBSHIELDVERSION to 4 and change the pins i getting like the photo.

So the power supply is good but in the new setup its something that gives wrong colors.

Have you initialised the display like this too?

#define A    A0
#define B    A1
#define C    A2
#define D    RX
#define LAT  TX 
#define CLK  D6
#define OE   D7

RGBmatrixPanel matrix(A, B, C, D, CLK, LAT, OE, true, 64);

I have all like you write @ScruffR but false instead of true in the end of the matrix row becouse do i put true its not shows anything but true it shows what i whant but half text in wrong color.

Odd. This provides a full color image on mine.
Could it be that the shield got a cold solder joint or a “dead” RX pin?
I guess you are not using Serial1 in your sketch.

I have seen that issue when using a breadboard instead of the shield with some bad wiring, but I can’t quite remember which pin it was, but I guess D as this is the extra pin for 32 rows.

The “D” line on RX may be affected somehow.

@ScruffR ok, i am using breadboard right now as prototype so can be bad pins.

@peekay123 ok, taking a look at the RX pin.

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I have now tried to change the cable for RX and its no differents so dont think it is RX pin if there is no special i need todo to get RX to work with photon.

What happens when you don’t use text and just draw a single one color box over the entire panel?

Red, then green then blue…

When i put Red on the whole screen i get red on the top and blue on the bottom.

When i put Blue on the whole screen i get blue on the top and red on the bottom.

When i put Green on the whole screen i get green on the whole screen.

Some idea about what can be wrong then?

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Try swapping R2(D3) and B2(D5) round


Thanks for the help everyone! Its was that two pins i most switched.