Particle Photon and Adafruit 32x64 RGB LED Matrix


@peekay123 First thank you so much for your software and all your assistance with the hardware.

I wonder if there’s any way we can gently encourage you to run off a batch of your excellent boards or make them available on OSHPark. Wiring difficulties seem to be a huge issue for al of of us newer people, and your PCB makes that a lot easier.


@OracleJ, no encouragement needed! I’m working on getting a V3 board I made which doesn’t use surface mount stuff and is easier to build. It looks like this:

I’m putting together the BOM and the board on OSHPark as we speak so stay tuned.


That looks great and is very welcome news. Thank you for making this available, I’m looking forward to setting it up.

Is that a female header on the other side of the board so it will mount without a cable? And the board looks to be around 2x3 square inches? Does the Photon have any IO left over that could be broken out near the prototyping area?


The board is now available on OSHPark. A project description includes the BOM.

Order from OSH Park



Thank you for making your board file available. I have a question though. It appears the board puts pins R1 and G1 on the panel on Photon pins WKP/A7 and A5 respectively. The wiring you suggested on this thread puts them on Photon pins D0 and D1 respectively and the RGBmatrixPanel library your pong clock uses appears to have these pins hard coded to D0 and D1. Do I have to change the RGBmatrixPanel library or am I missing something somewhere?


The reason behind moving these pins is to free up the I2C pins (D0/D1) to allow for easy integration of additional sensors.

That’s in order to take the library sample as is, but the library can be tweaked to remap the pins as you see fit.


@OracleJ, the RGBMatrixPanel library sets the board version to 4. That board was designed with a microSD card onboard but used surface mount components. The board I posted on OSHPark is a redesigned V2 board which, as @ScruffR pointed out, frees up I2C and RX/TX for peripherals. Just be sure to change the board version #define to 3 though this will require that you install the library files in Workbench or copy them in the Web IDE so you can edit the necessary file.


Thanks for your reply. Your project name on OSHPark has “V3” so I understood from that that I have to change your “RGBPongClock” file to use version 3.

My question was about the exact portion that ScruffR pasted. In his post, you can see the RGBMatrixPanel file has R1 on D0 and G1 on D1. These are the I2C pins on the Photon, and your PCB appears to use A5 and A7 instead. So that file will need to be modified was well.

I understand freeing up I2C is a very good thing, and the pin reassignment is a positive change. I just don’t want to end up in the frustrating situation of putting it all together and having nothing work with no idea why. I don’t see how anyone would know to change the RGBMatrix panel file especially to those specific pins, and without ScruffR confirming I should tweak the library to remap the pins, I still wouldn’t be sure that was needed.


@OracleJ, we (forum members) are always here to help!


@peekay123 i just ordered from oshpark and now im searching all the parts to assemble it. in the description of the Board the Link for C1 (0.1uF Cap) leads me to the barrel jack. What would be the link to the Capacitor? :slight_smile:


@faziban, thanks for catching that!! I fixed the link. :wink:


@peekay123 Thank you very much! I placed the orders and get to sodering as soon as the hardware arrives. Ill be trying to get it to run with this power supply:
Ill keep you updated, thank you everyone for the help so far!


Ill keep you guys updated!
Thanks very much again to @peekay123!!!


I just realised, that the link for the schottky diode is the one for the capacitor and thats why i havent ordered and received a diode :smiley: @peekay123 do you have the link to that diode?


@faziban Fwiw, I believe the circuit is powered through that diode as a reverse power protector. If you replace it with a jumper, the project will still work, you will only lose this protection, so you need to be very sure you triple check the polarity of your power supply before installing the photon and connecting the matrix. I hope peekay123 can respond to confirm that, but looking at the foil pattern on the PCB, it appears to be the case.

I ordered my parts from China via epacket, so I’ll still be waiting a while before I can warm up the soldering iron. I’m looking forward to hearing about your progress.


@faziban, @OracleJ is correct in regards to the jumper. I thought I had fixed the link to the diode on OSHPark! Nonetheless, I recommend a 1A schottky diode like this one:


@OracleJ Thanks very much, ill see if i can find some lying around in the company. :wink: or il do it with a jumper and tripple check the powersupply


@peekay123 thanks for that :slight_smile: ill try it out tomorrow!


i havent found time to try anything out yet.but i just ordered the diodes with some other parts. i will just assemble it next week and test it. sorry for the delay, some concerts are comming up and i dont get to stuff



I am currently trying to connect my 16x32 led matrix (1/8 scan, 32 x 16 cm) to my photon using the RGBMatrixPanel library. The left side (16 x 16 block) of my panel works absolutely fine; by calling matrix.drawPixel(x,y,color) for some pixel at this side of the matrix, the right LED lights up. As soon as I call it for some pixel on the other side of the matrix, multiple LEDs light up and the location seems to be incorrect. I defined and used the exact same pins as they are stated in the library (I already checked them three times).

I tried to visualize the problem by drawing a 2x2 pixel block and moving it from the ‘good side’ of the panel to the ‘bad side’. I hope one of you is able to help me with this problem!

Thanks in advance!