Add WS2812B keypress demo

99_raindrop/main.go

@@ -0,0 +1,146 @@
+package main
+
+import (
+	"machine"
+	"time"
+
+	pio "github.com/tinygo-org/pio/rp2-pio"
+	"github.com/tinygo-org/pio/rp2-pio/piolib"
+)
+
+func NewWS2812B(pin machine.Pin) *piolib.WS2812B {
+	s, _ := pio.PIO0.ClaimStateMachine()
+	ws, _ := piolib.NewWS2812B(s, pin)
+	ws.EnableDMA(true)
+	return ws
+}
+
+func main() {
+	// 16 random colors
+	randCol := 0
+	randColors := [16]uint32{
+		0xFF00FF00, 0xFF0000FF, 0xFFFF0000, 0xFFFFFF00,
+		0xFFFF00FF, 0xFF00FFFF, 0xFF800000, 0xFF008000,
+		0xFF000080, 0xFF808000, 0xFF800080, 0xFF008080,
+		0xFFC00000, 0xFF00C000, 0xFF0000C0, 0xFFC000C0,
+	}
+
+	colors := []uint32{
+		0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF,
+		0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF,
+		0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF,
+	}
+
+	ws := NewWS2812B(machine.GPIO1)
+
+	colPins := []machine.Pin{
+		machine.GPIO5,
+		machine.GPIO6,
+		machine.GPIO7,
+		machine.GPIO8,
+	}
+
+	rowPins := []machine.Pin{
+		machine.GPIO9,
+		machine.GPIO10,
+		machine.GPIO11,
+	}
+
+	for _, c := range colPins {
+		c.Configure(machine.PinConfig{Mode: machine.PinOutput})
+		c.Low()
+	}
+
+	for _, c := range rowPins {
+		c.Configure(machine.PinConfig{Mode: machine.PinInputPulldown})
+	}
+
+	input := make(chan int, 12)
+
+	update := time.NewTicker(10 * time.Millisecond)
+	decay := time.NewTicker(50 * time.Millisecond)
+	for {
+		select {
+		case key := <-input:
+			randCol++
+			colors[key] = randColors[randCol%16]
+		case <-decay.C:
+			for i := range colors {
+				g := ((colors[i] >> 24) & 0xFF) >> 1
+				r := ((colors[i] >> 16) & 0xFF) >> 1
+				b := ((colors[i] >> 8) & 0xFF) >> 1
+				colors[i] = (g << 24) | (r << 16) | (b << 8) | 0
+			}
+		case <-update.C:
+			ws.WriteRaw(colors)
+		default:
+			// COL1
+			colPins[0].High()
+			colPins[1].Low()
+			colPins[2].Low()
+			colPins[3].Low()
+			time.Sleep(1 * time.Millisecond)
+
+			if rowPins[0].Get() {
+				input <- 0
+			}
+			if rowPins[1].Get() {
+				input <- 1
+			}
+			if rowPins[2].Get() {
+				input <- 2
+			}
+
+			// COL2
+			colPins[0].Low()
+			colPins[1].High()
+			colPins[2].Low()
+			colPins[3].Low()
+			time.Sleep(1 * time.Millisecond)
+
+			if rowPins[0].Get() {
+				input <- 3
+			}
+			if rowPins[1].Get() {
+				input <- 4
+			}
+			if rowPins[2].Get() {
+				input <- 5
+			}
+
+			// COL3
+			colPins[0].Low()
+			colPins[1].Low()
+			colPins[2].High()
+			colPins[3].Low()
+			time.Sleep(1 * time.Millisecond)
+
+			if rowPins[0].Get() {
+				input <- 6
+			}
+			if rowPins[1].Get() {
+				input <- 7
+			}
+			if rowPins[2].Get() {
+				input <- 8
+			}
+
+			// COL4
+			colPins[0].Low()
+			colPins[1].Low()
+			colPins[2].Low()
+			colPins[3].High()
+			time.Sleep(1 * time.Millisecond)
+
+			if rowPins[0].Get() {
+				input <- 9
+			}
+			if rowPins[1].Get() {
+				input <- 10
+			}
+			if rowPins[2].Get() {
+				input <- 11
+			}
+		}
+	}
+}