What is Clock pin and Data pin, Orientation in Grove LED bar I'm trying to use Grove LED Bar with Arduino




  Grove – LED Bar is comprised of a 10 segment LED gauge bar and an
  MY9221 LED controlling chip. It can be used as an indicator for
  remaining battery life, voltage, water level, music volume or other
  values that require a gradient display. There are 10 LED bars in the
  LED bar graph: one red, one yellow, one light green, and seven green
  bars. Demo code is available to get you up and running quickly. It
  lights up the LEDs sequentially from red to green, so the entire bar
  graph is lit up in the end.


In the github example there are Clock pin, Data pin and Orientation.

// Arduino Clock pin, Data pin, Orientation 
// Grove_LED_Bar bar(7, 6, 0);  


https://github.com/Seeed-Studio/Grove_LED_Bar/blob/master/LP%20examples/BasicControl/BasicControl.ino

But I have no idea what are they. Where can I find the documentation for them?
on the LED circuit board there are a few connections, notably DI and DCKI.

The DI pin is the data pint and DCKI is the clock pin.

According to the header orientation is about which way the pins are oriented red-to-green or green-to-red. It affects at which end led 1 is.