Generic

What I like on your driver:
- small
- low memory
- text scaling is great (no fonts necessary)

So I did some updates to have some functions more:
- generic driver for more TFT like ili93xx
I added just a specific init routine. The spi commands are most the same.
So just the init was the problem.

But the fill rectangle function was not proper working.
I changed the following:
#self.set_window(x,y,x+w-1,y+1-w)
self.set_window(x,y,x+w-1,y+w-1)

My version works on st7789 and the ili93xx. Your version is st7789 specific.
I did not a closer research why.

If you are interested on my changes then please let me know.