evidently this is something like a port expander where a microcontroller works "with 12 groups of 8-bit LED lights" expanded using 74HCXX chips... From the main page, scroll down until you get to the questions and answers section. Right after that you'll see a purple board, that's faded on the bottom. click on: "see all descriptions". the descriptions list three parts of the board this is the third part: 3. This test circuit is controlled by a single-chip microcomputer to work with 12 groups of 8-bit LED lights. Each group is composed of *****HC573 and 74HC164. One group can control 8 LEDs, 12 groups in total. Figure 1 is the control schematic diagram of one group. When working normally, all LED lights are on and can flash.