maintenance mode (timeout watchdog reworked)

src/boot.cpp

@@ -4,37 +4,11 @@
 // Local logging tag
 static const char TAG[] = __FILE__;
 
-// start local web server with user interface for maintenance mode
+static hw_timer_t *wdTimer = NULL;
-// used for manually uploading a firmware file via wifi
+static WebServer server(80);
+static TaskHandle_t RestartHandle;
 
-void start_boot_menu(void) {
+static const char *loginMenu =
-
-  uint8_t mac[6];
-  char clientId[20];
-  unsigned long timeout = millis();
-
-  // hash 6 byte MAC to 4 byte hash
-  esp_eth_get_mac(mac);
-  const uint32_t hashedmac = myhash((const char *)mac, 6);
-  snprintf(clientId, 20, "paxcounter_%08x", hashedmac);
-
-  const char *host = clientId;
-  const char *ssid = WIFI_SSID;
-  const char *password = WIFI_PASS;
-
-  // set runmode normal makes watchdog booting to production if triggered
-  RTC_runmode = RUNMODE_NORMAL;
-
-  // setup watchdog, based on esp32 timer2 interrupt
-  hw_timer_t *timer = NULL;
-  timer = timerBegin(2, 80, true);                 // timer 2, div 80, countup
-  timerAttachInterrupt(timer, &esp_restart, true); // callback for device reset
-  timerAlarmWrite(timer, BOOTTIMEOUT * 1000000, false); // set time in us
-  timerAlarmEnable(timer);                              // enable watchdog
-
-  WebServer server(80);
-
-  const char *loginMenu =
     "<form name='loginForm'>"
     "<table width='20%' bgcolor='A09F9F' align='center'>"
     "<tr>"
@@ -55,7 +29,7 @@ void start_boot_menu(void) {
     "function start(form) {window.open('/serverIndex')}"
     "</script>";
 
-  const char *serverIndex =
+static const char *serverIndex =
     "<script "
     "src='https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/"
     "jquery.min.js'></script>"
@@ -95,6 +69,44 @@ void start_boot_menu(void) {
     "});"
     "</script>";
 
+void IRAM_ATTR watchdog() { xTaskResumeFromISR(RestartHandle); }
+
+// start local web server with user interface for maintenance mode
+// used for manually uploading a firmware file via wifi
+
+void start_boot_menu(void) {
+
+  uint8_t mac[6];
+  char clientId[20];
+
+  // hash 6 byte MAC to 4 byte hash
+  esp_eth_get_mac(mac);
+  const uint32_t hashedmac = myhash((const char *)mac, 6);
+  snprintf(clientId, 20, "paxcounter_%08x", hashedmac);
+
+  const char *host = clientId;
+  const char *ssid = WIFI_SSID;
+  const char *password = WIFI_PASS;
+
+  // set runmode normal makes watchdog booting to production if triggered
+  RTC_runmode = RUNMODE_NORMAL;
+
+  // setup restart handle task for resetting ESP32, which is callable from ISR
+  // (because esp_restart() from ISR would trigger the ESP32 task watchdog)
+  xTaskCreate(
+      [](void *p) {
+        vTaskSuspend(NULL);
+        ESP.restart();
+      },
+      "Restart", configMINIMAL_STACK_SIZE, NULL, (3 | portPRIVILEGE_BIT),
+      &RestartHandle);
+
+  // setup watchdog, based on esp32 timer2 interrupt
+  wdTimer = timerBegin(0, 80, true);              // timer 0, div 80, countup
+  timerAttachInterrupt(wdTimer, &watchdog, true); // callback for device reset
+  timerAlarmWrite(wdTimer, BOOTDELAY * 1000000, false); // set time in us
+  timerAlarmEnable(wdTimer);                            // enable watchdog
+
   WiFi.disconnect(true);
   WiFi.config(INADDR_NONE, INADDR_NONE,
               INADDR_NONE); // call is only a workaround for bug in WiFi class
@@ -109,39 +121,31 @@ void start_boot_menu(void) {
   // 1st try
   WiFi.begin(ssid, password);
   while (WiFi.status() == WL_DISCONNECTED) {
-    if ((long)(millis() - timeout) > (BOOTDELAY * 1000))
-      esp_restart();
-    else
     delay(500);
   }
   // 2nd try
   if (WiFi.status() != WL_CONNECTED) {
     WiFi.begin(ssid, password);
-    while (WiFi.status() != WL_CONNECTED) {
-      if ((long)(millis() - timeout) > (BOOTDELAY * 1000))
-        esp_restart();
-      else
     delay(500);
   }
-  }
 
   MDNS.begin(host);
-  timerWrite(timer, 0); // reset timer (feed watchdog)
+  timerWrite(wdTimer, 0); // reset timer (feed watchdog)
 
-  server.on("/", HTTP_GET, [&server, &loginMenu]() {
+  server.on("/", HTTP_GET, []() {
     server.sendHeader("Connection", "keep-alive");
     server.send(200, "text/html", loginMenu);
   });
 
-  server.on("/serverIndex", HTTP_GET, [&server, &serverIndex, &timer]() {
+  server.on("/serverIndex", HTTP_GET, []() {
-    timerWrite(timer, 0); // reset timer (feed watchdog)
+    timerAlarmWrite(wdTimer, BOOTTIMEOUT * 1000000, false); // set time in us
     server.sendHeader("Connection", "keep-alive");
     server.send(200, "text/html", serverIndex);
   });
 
   server.on(
       "/update", HTTP_POST,
-      [&server]() {
+      []() {
         server.sendHeader("Connection", "close");
         server.send(200, "text/plain", (Update.hasError()) ? "FAIL" : "OK");
         WiFi.disconnect(true);
@@ -149,7 +153,7 @@ void start_boot_menu(void) {
       },
 
       // handling uploading firmware file
-      [&server, &timer]() {
+      []() {
         bool success = false;
         HTTPUpload &upload = server.upload();
 

src/main.cpp

@@ -51,7 +51,6 @@ So don't do it if you do not own a digital oscilloscope.
 -------------------------------------------------------------------------------
 0	displayIRQ -> display refresh -> 40ms (DISPLAYREFRESH_MS)
 1 ppsIRQ -> pps clock irq -> 1sec
-2 watchdog -> used in boot.cpp
 3	MatrixDisplayIRQ -> matrix mux cycle -> 0,5ms (MATRIX_DISPLAY_SCAN_US)