espat: add support for esp8266/esp32 Wifi adaptor AT command set with net-compatible UDP support

Signed-off-by: Ron Evans <ron@hybridgroup.com>
2026-08-19 06:03:57 +00:00 · 2019-02-23 17:07:29 +01:00
parent ae53ea7d81
commit 0c2924cd77
8 changed files with 1073 additions and 0 deletions
@@ -0,0 +1,111 @@
+// This is a sensor hub that uses a ESP8266/ESP32 running on the device UART1.
+// It creates a UDP "server" you can use to get info to/from your computer via the microcontroller.
+//
+// In other words:
+// Your computer <--> UART0 <--> MCU <--> UART1 <--> ESP8266 <--> INTERNET
+//
+package main
+
+import (
+	"machine"
+	"time"
+
+	"github.com/tinygo-org/drivers/espat"
+)
+
+// change actAsAP to true to act as an access point instead of connecting to one.
+const actAsAP = false
+
+// access point info
+const ssid = "YOURSSID"
+const pass = "YOURPASS"
+
+// change these to connect to a different UART or pins for the ESP8266/ESP32
+var (
+	uart       = machine.UART1
+	tx   uint8 = machine.D10
+	rx   uint8 = machine.D11
+
+	console = machine.UART0
+
+	adaptor *espat.Device
+)
+
+func main() {
+	uart.Configure(machine.UARTConfig{TX: tx, RX: rx})
+
+	// Init esp8266
+	adaptor = espat.New(uart)
+	adaptor.Configure()
+
+	readyled := machine.GPIO{machine.LED}
+	readyled.Configure(machine.GPIOConfig{Mode: machine.GPIO_OUTPUT})
+	readyled.High()
+
+	// first check if connected
+	if adaptor.Connected() {
+		console.Write([]byte("Connected to wifi adaptor.\r\n"))
+		adaptor.Echo(false)
+
+		if actAsAP {
+			provideAP()
+		} else {
+			connectToAP()
+		}
+	} else {
+		console.Write([]byte("\r\n"))
+		console.Write([]byte("Unable to connect to wifi adaptor.\r\n"))
+		return
+	}
+
+	// now make UDP connection
+	laddr := &espat.UDPAddr{Port: 2222}
+	console.Write([]byte("Loading UDP listener...\r\n"))
+	conn, _ := adaptor.ListenUDP("UDP", laddr)
+
+	console.Write([]byte("Waiting for data...\r\n"))
+	data := make([]byte, 50)
+	blink := true
+	for {
+		n, _ := conn.Read(data)
+		if n > 0 {
+			console.Write(data[:n])
+			console.Write([]byte("\r\n"))
+			conn.Write([]byte("hello back\r\n"))
+		}
+		blink = !blink
+		if blink {
+			readyled.High()
+		} else {
+			readyled.Low()
+		}
+		time.Sleep(500 * time.Millisecond)
+	}
+
+	// Right now this code is never reached. Need a way to trigger it...
+	console.Write([]byte("Disconnecting UDP...\r\n"))
+	conn.Close()
+	console.Write([]byte("Done.\r\n"))
+}
+
+// connect to access point
+func connectToAP() {
+	console.Write([]byte("Connecting to wifi network...\r\n"))
+	adaptor.SetWifiMode(espat.WifiModeClient)
+	adaptor.ConnectToAP(ssid, pass, 10)
+	console.Write([]byte("Connected.\r\n"))
+	console.Write([]byte(adaptor.GetClientIP()))
+	console.Write([]byte("\r\n"))
+}
+
+// provide access point
+func provideAP() {
+	console.Write([]byte("Starting wifi network as access point '"))
+	console.Write([]byte(ssid))
+	console.Write([]byte("'...\r\n"))
+	adaptor.SetWifiMode(espat.WifiModeAP)
+	adaptor.SetAPConfig(ssid, pass, 7, espat.WifiAPSecurityWPA2_PSK)
+	console.Write([]byte("Ready.\r\n"))
+	console.Write([]byte(adaptor.GetAPIP()))
+	console.Write([]byte("\r\n"))
+}