epd2in66b: Waveshare 2.66inch E-Paper Display Module (B) for Raspberry Pi Pico (#673)

epd2in66b: add working driver

Co-authored-by: Thomas Richner <thomas.richner@oviva.com>

examples/waveshare-epd/epd2in66b/main.go

@@ -0,0 +1,84 @@
+package main
+
+import (
+	"image/color"
+	"machine"
+	"time"
+
+	"tinygo.org/x/drivers"
+	"tinygo.org/x/drivers/waveshare-epd/epd2in66b"
+	"tinygo.org/x/tinyfont"
+	"tinygo.org/x/tinyfont/freemono"
+)
+
+var (
+	black = color.RGBA{0, 0, 0, 0xff}
+	white = color.RGBA{0xff, 0xff, 0xff, 0xff}
+	red   = color.RGBA{0xff, 0, 0, 0xff}
+)
+
+func main() {
+	machine.Serial.Configure(machine.UARTConfig{})
+	time.Sleep(2 * time.Second)
+
+	machine.SPI1.Configure(machine.SPIConfig{
+		Frequency: epd2in66b.Baudrate,
+	})
+
+	println("started")
+
+	// in case you have a Pico module, you can directly use
+	// dev, err := epd2in66b.NewPicoModule()
+
+	display := epd2in66b.New(machine.SPI1)
+
+	cfg := epd2in66b.Config{
+		DataPin:       machine.GP8,
+		ChipSelectPin: machine.GP9,
+		ResetPin:      machine.GP12,
+		BusyPin:       machine.GP13,
+	}
+	err := display.Configure(cfg)
+	if err != nil {
+		panic(err)
+	}
+
+	err = display.Reset()
+	if err != nil {
+		panic(err)
+	}
+
+	println("draw checkerboard")
+	drawCheckerBoard(&display)
+
+	println("draw 'hello'")
+	tinyfont.WriteLineRotated(&display, &freemono.Bold24pt7b, 40, 10, "Hello!", white, tinyfont.ROTATION_90)
+	tinyfont.WriteLineRotated(&display, &freemono.Bold12pt7b, 10, 10, "tinygo rocks", white, tinyfont.ROTATION_90)
+	err = display.Display()
+	if err != nil {
+		panic(err)
+	}
+}
+
+func drawCheckerBoard(display drivers.Displayer) {
+	s := 8
+	width, height := display.Size()
+	for x := 0; x <= int(width)-s; x += s {
+		for y := 0; y <= int(height)-s; y += s {
+			c := red
+			if (x/s)%2 == (y/s)%2 {
+				c = black
+			}
+
+			showRect(display, x, y, s, s, c)
+		}
+	}
+}
+
+func showRect(display drivers.Displayer, x int, y int, w int, h int, c color.RGBA) {
+	for i := x; i < x+w; i++ {
+		for j := y; j < y+h; j++ {
+			display.SetPixel(int16(i), int16(j), c)
+		}
+	}
+}