Added UDP support

examples/wifinina/udpstation/main.go

@@ -0,0 +1,100 @@
+// This is a sensor station that uses a ESP32 running nina-fw over SPI.
+// It creates a UDP connection you can use to get info to/from your computer via the microcontroller.
+//
+// In other words:
+// Your computer <--> UART0 <--> MCU <--> SPI <--> ESP32
+//
+package main
+
+import (
+	"machine"
+	"strconv"
+	"time"
+
+	"tinygo.org/x/drivers/net"
+	"tinygo.org/x/drivers/wifinina"
+)
+
+// access point info
+const ssid = ""
+const pass = ""
+
+// IP address of the server aka "hub". Replace with your own info.
+const hubIP = ""
+
+// these are the default pins for the Arduino Nano33 IoT.
+// change these to connect to a different UART or pins for the ESP8266/ESP32
+var (
+
+	// this is the ESP chip that has the WIFININA firmware flashed on it
+	// these are the default pins for the Arduino Nano33 IoT.
+	adaptor = &wifinina.Device{
+		SPI:   machine.NINA_SPI,
+		CS:    machine.NINA_CS,
+		ACK:   machine.NINA_ACK,
+		GPIO0: machine.NINA_GPIO0,
+		RESET: machine.NINA_RESETN,
+	}
+)
+
+func main() {
+
+	// Init esp8266/esp32
+	// Configure SPI for 8Mhz, Mode 0, MSB First
+	machine.NINA_SPI.Configure(machine.SPIConfig{
+		Frequency: 8 * 1e6,
+		MOSI:      machine.NINA_MOSI,
+		MISO:      machine.NINA_MISO,
+		SCK:       machine.NINA_SCK,
+	})
+	adaptor.Configure()
+
+	// connect to access point
+	connectToAP()
+
+	// now make UDP connection
+	ip := net.ParseIP(hubIP)
+	raddr := &net.UDPAddr{IP: ip, Port: 2222}
+	laddr := &net.UDPAddr{Port: 2222}
+
+	println("Dialing UDP connection...")
+	conn, _ := net.DialUDP("udp", laddr, raddr)
+
+	for {
+		// send data
+		println("Sending data...")
+		for i := 0; i < 25; i++ {
+			conn.Write([]byte("hello " + strconv.Itoa(i) + "\r\n"))
+		}
+		time.Sleep(1000 * time.Millisecond)
+	}
+
+	// Right now this code is never reached. Need a way to trigger it...
+	println("Disconnecting UDP...")
+	conn.Close()
+	println("Done.")
+}
+
+// connect to access point
+func connectToAP() {
+	time.Sleep(2 * time.Second)
+	message("Connecting to " + ssid)
+	adaptor.SetPassphrase(ssid, pass)
+	for st, _ := adaptor.GetConnectionStatus(); st != wifinina.StatusConnected; {
+		message("Connection status: " + st.String())
+		time.Sleep(1 * time.Second)
+		st, _ = adaptor.GetConnectionStatus()
+	}
+	message("Connected.")
+	time.Sleep(2 * time.Second)
+	ip, _, _, err := adaptor.GetIP()
+	for ; err != nil; ip, _, _, err = adaptor.GetIP() {
+		message(err.Error())
+		time.Sleep(1 * time.Second)
+	}
+	message(ip.String())
+}
+
+func message(msg string) {
+	println(msg, "\r")
+}