question re:Philips PCF8833 Graphics LCD tutorial

This tutorial says to connect:

  • CS: Arduino Pin 9
  • SCLK: Arduino Pin 7
  • SDATA: Arduino Pin 5

In the past, I have interfaced with i2c sensors, in which SCLK had to connect to analog 5 and SDATA had to connect to analog 4. Obviously that's not the case now, but does SDATA connect to analog or digital?

Taking a quick look at the PCF8833 datasheet says the interface is "I2C-like", not "I2C": it uses 9-bit bytes, and may violate some of the I2C protocols (or may not: it was a really quick look).

So the library authors bit-banged the interface using non-I2C pins.