ller library, BUT: For driving 64x64 matrices, this boards/shield requires soldering: You need to connect P4 to GND and P8 zu #E. Either solder two small wires or jumpers like I did (see pictures: before/after). This would be easier if the board already came with jumpers in the right place. I found the tip here: https://w2.electrodragon.com/Board-dat/MPC/MPC1073-DAT/MPC1073-test-log-dat/MPC1073-test-log-dat.md#more-demos However, contrary to what it says there, --led-multiplexing=0 (instead of 1) did the trick so this demo worked after soldering: sudo examples-api-use/demo --led-rows=64 --led-cols=64 --led-multiplexing=0 However, I get quite a bit of ghosting/artefacts when displaying small images and animations on a chain of just 2 64x64 matrices, even after tweaking with things like --led-pwm-lsb-nanoseconds 50 and --led-limit-refresh=240. Thus, driving two 64x64 matrices already seems to be the limit of what the hzeller library and a Pi4B can do, because of the many address lines that 64 x 64 matrices have.
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2. Try the python demo code here: https://w2.electrodragon.com/gollum/search?q=CH423-dat.md Thank you!
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2W It is working great, and the 3rd connector is not being used. I also want to add your I2C to GPIO IO Expander Breaktout Board CH423 as I need 4 more GPIO pins from the Pi. Can I, or how do I connect the expander Board to the HAT or the Pi Zero? Or can I use the spare HAT connector to add 4 GPIO pins Thanks.
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age may vary. I used it on a PI5 with this library: https://github.com/bitslip6/rpi-gpu-hub75-matrix, and was able to get 9600Hz operation for 64x64 panels. There is no issue with this hardware and any PI model, only your software and OS configuration. 5 stars.
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pitch breadboard. The distance between the header pin rows is 0.75"/19mm rather than a multiple of 0.1". That said, the board is still fine for my purpose as I wanted a basic working 4808 board to experiment with UPDI programming and testing functions of the 4808 chip before making my own custom board. I can do this with dupont cables directly off the header pins. The board powered up from the USB port first time and is running some internal code that flashes the LED so it can be seen to be working. The voltage default is set to 3.3V so I had to remove the solder power jumper and change to 5V for my purposes. It would be useful to have a complete circuit diagram to see how the power supplies and reset circuit works, there is only a pinout and connections to the 4808 shown in the information. (there is a 100nF cap to reset from the RTS pin on the serial port, so the board resets when the serial port is opened) The expansion connector on the back of the PCB was not fitted to my boards. This was ideal as I don't need it.
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