Add an example for using critical and safe loops

examples/ModelessWithInterrupts/ModelessWithInterrupts.ino

@@ -0,0 +1,87 @@
+#if defined(ESP8266)
+#include <ESP8266WiFi.h>          //https://github.com/esp8266/Arduino
+#else
+#include <WiFi.h>
+#endif
+
+//needed for library
+#include <DNSServer.h>
+#include <ESPAsyncWebServer.h>
+#include <ESPAsyncWiFiManager.h>         //https://github.com/tzapu/WiFiManager
+
+AsyncWebServer server(80);
+DNSServer dns;
+AsyncWiFiManager wifiManager(&server,&dns);
+
+volatile boolean guard = true;
+const uint32_t callCycleCount = ESP.getCpuFreqMHz() * 1024 / 8;
+
+/*
+ * If some other code was in the process of calling a method in
+ * WiFi, ESP or EEPROM, and we do too, there is a very good chance
+ * a reset will happen.
+ */
+void ICACHE_RAM_ATTR interruptFunction() {
+	/*
+	 * This is equivalent to:
+	 * timer0_write(ESP.getCycleCount() + ESP.getCpuFreqMHz() * 1024 / 8)
+	 * But that could clash with the main thread code.
+	 */
+    uint32_t ccount;
+    __asm__ __volatile__("esync; rsr %0,ccount":"=a" (ccount));
+
+	timer0_write(ccount + callCycleCount);
+
+	if (!guard) {
+		// An example call that would cause a reset if it happens
+		// to be called while AsyncWiFiManager is also calling
+		// methods that modify flash.
+		ESP.getChipId();
+	}
+}
+
+void setup() {
+    // put your setup code here, to run once:
+    Serial.begin(115200);
+
+    //WiFiManager
+    //Local intialization. Once its business is done, there is no need to keep it around
+    //reset saved settings
+    //wifiManager.resetSettings();
+
+    //set custom ip for portal
+    //wifiManager.setAPConfig(IPAddress(10,0,1,1), IPAddress(10,0,1,1), IPAddress(255,255,255,0));
+
+    //fetches ssid and pass from eeprom and tries to connect
+    //if it does not connect it starts an access point with the specified name
+    //here  "AutoConnectAP"
+    //and goes into a blocking loop awaiting configuration
+    //wifiManager.autoConnect("AutoConnectAP");
+    //or use this for auto generated name ESP + ChipID
+    //wifiManager.autoConnect();
+    wifiManager.startConfigPortalModeless("ModelessAP", "Password");
+
+
+ server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){
+    request->send(200, "text/plain", "Hello World");
+  });
+
+    // Set up some code that could cause a reset.
+	guard = true;
+	timer0_isr_init();
+	timer0_attachInterrupt(interruptFunction);
+	timer0_write(ESP.getCycleCount() + ESP.getCpuFreqMHz() * 1024);	// Wait 2 seconds before displaying
+	updateDisplay = false;
+}
+
+void loop() {
+    // put your main code here, to run repeatedly:
+	// This can be called with guarding interrupt routines - so
+	// interrupt routines can interrupt it!
+    wifiManager.safeLoop();
+
+    guard = true;
+	// This call can not be interrupted without possibly causing a reset.
+	wifiManager.criticalLoop();
+    guard = false;
+}