This is one board with the LED part of the 0201 version from #reDOT combined with a small STM8 microcontroller on the back. The microcontroller drives all LEDs directly with multiplexing. For controlling a UART interface is available. The dimensions are like a DIP-6 package. For easy connection of multiple PCBs, the pads are castellated. Also the supply rails are available on both sides. So multiple of these display can be soldered together to a bigger display without the need of additional wiring.

This is planed as chainable. Therefore connected pins for the supply rails are available on both sides. The idea is to solder them together like I did with #tiny7. The RX pin of the second display would be connected to the TX pin of the first one (the most left one). So the firmware must implement some kind of UART-shiftregister to control all displays with same firmware

     MASTER                  DISPLAY #1          DISPLAY #2
+-----------------+          +--------+          +--------+
|    UART-USB     |---+5V--->|VCC--VCC|---+5V--->|VCC--VCC|  
|    or other   TX|----->----|RX    TX|--------->|RX    TX|->
| microcontroller |---GND--->|GND--GND|---GND--->|GND  GND|   
+-----------------+          +--------+          +--------+  
             unneeded data flowing out at the end of the chain

Project is not yet ready. For prototyping specially for the software #reDOT and a cheap chinese development board with a STM8 will be used (see also there for a early version of the firmware)