max7219: add driver support

examples/max72xx/main.go

@@ -0,0 +1,135 @@
+package main
+
+import (
+	"machine"
+	"time"
+
+	"tinygo.org/x/drivers/max72xx"
+)
+
+// example for a 4 digit 7 segment display
+func main() {
+	// Pins for Arduino Nano 33 IOT
+	err := machine.SPI0.Configure(machine.SPIConfig{
+		SDO:       machine.D11, // default SDO pin
+		SCK:       machine.D13, // default sck pin
+		LSBFirst:  false,
+		Frequency: 10000000,
+	})
+
+	if err != nil {
+		println(err.Error())
+	}
+
+	driver := max72xx.NewDevice(machine.SPI0, machine.D6)
+	driver.Configure()
+
+	digitNumber := 4
+
+	driver.StopDisplayTest()
+	driver.SetDecodeMode(4)
+	driver.SetScanLimit(4)
+	driver.StopShutdownMode()
+
+	for i := 1; i < int(digitNumber); i++ {
+		driver.WriteCommand(byte(i), byte(Blank))
+	}
+
+	for {
+		for _, character := range characters {
+			println("writing", "characterValue:", character.String())
+			driver.WriteCommand(byte(4), byte(character))
+			driver.WriteCommand(byte(3), byte(character))
+			driver.WriteCommand(byte(2), byte(character))
+			driver.WriteCommand(byte(1), byte(character))
+			time.Sleep(500 * time.Millisecond)
+
+		}
+		time.Sleep(time.Second)
+	}
+
+}
+
+var characters = []Character{
+	Zero,
+	One,
+	Two,
+	Three,
+	Four,
+	Five,
+	Six,
+	Seven,
+	Eight,
+	Nine,
+	Dash,
+	E,
+	H,
+	L,
+	P,
+	Blank,
+	Dot,
+}
+
+// Each bit translates to a pin, which is driven high or low
+type Character byte
+
+func (char Character) String() string {
+	switch char {
+	case Zero:
+		return "0"
+	case One:
+		return "1"
+	case Two:
+		return "2"
+	case Three:
+		return "3"
+	case Four:
+		return "4"
+	case Five:
+		return "5"
+	case Six:
+		return "6"
+	case Seven:
+		return "7"
+	case Eight:
+		return "8"
+	case Nine:
+		return "9"
+	case Dash:
+		return "-"
+	case E:
+		return "E"
+	case H:
+		return "H"
+	case L:
+		return "L"
+	case P:
+		return "P"
+	case Blank:
+		return ""
+	case Dot:
+		return "."
+	}
+
+	return ""
+}
+
+const (
+	Zero  Character = 0 //126
+	One   Character = 1 //48
+	Two   Character = 2 // 109
+	Three Character = 3 // 121
+	Four  Character = 4
+	Five  Character = 5
+	Six   Character = 6
+	Seven Character = 7
+	Eight Character = 8
+	Nine  Character = 9
+	Dash  Character = 10
+	E     Character = 11
+	H     Character = 12
+	L     Character = 13
+	P     Character = 14
+	Blank Character = 15
+	Dot   Character = 128
+)