free up hw timer #1 (for future DCF77 use)

include/globals.h

@@ -105,8 +105,9 @@ extern std::set<uint16_t, std::less<uint16_t>, Mallocator<uint16_t>> macs;
 extern std::array<uint64_t, 0xff>::iterator it;
 extern std::array<uint64_t, 0xff> beacons;
 
-extern TaskHandle_t irqHandlerTask, wifiSwitchTask;
+extern TaskHandle_t irqHandlerTask;
-extern Timezone myTZ; // make Timezone myTZ globally available
+extern TimerHandle_t WifiChanTimer;
+extern Timezone myTZ;
 
 // application includes
 #include "led.h"

include/irqhandler.h

@@ -11,7 +11,6 @@
 #include "senddata.h"
 
 void irqHandler(void *pvParameters);
-void IRAM_ATTR ChannelSwitchIRQ();
 void IRAM_ATTR homeCycleIRQ();
 void IRAM_ATTR SendCycleIRQ();
 

include/wifiscan.h

@@ -9,6 +9,6 @@
 
 void wifi_sniffer_init(void);
 void IRAM_ATTR wifi_sniffer_packet_handler(void *buff, wifi_promiscuous_pkt_type_t type);
-void switchWifiChannel(void * parameter);
+void switchWifiChannel(TimerHandle_t xTimer);
 
 #endif

src/cyclic.cpp

@@ -41,7 +41,7 @@ void doHousekeeping() {
   if ((millis() >= nextRTCTimeSync) && (timeStatus() == timeSet)) {
     nextRTCTimeSync = millis() + TIME_WRITE_INTERVAL_RTC *
                                      60000; // set up next time sync period
-    if (!set_rtctime(now())) // epoch time
+    if (!set_rtctime(now()))                // epoch time
       ESP_LOGE(TAG, "RTC set time failure");
     else
       ESP_LOGI(TAG, "RTC time updated");
@@ -49,9 +49,6 @@ void doHousekeeping() {
 #endif
 
   // task storage debugging //
-  ESP_LOGD(TAG, "Wifiloop %d bytes left | Taskstate = %d",
-           uxTaskGetStackHighWaterMark(wifiSwitchTask),
-           eTaskGetState(wifiSwitchTask));
   ESP_LOGD(TAG, "IRQhandler %d bytes left | Taskstate = %d",
            uxTaskGetStackHighWaterMark(irqHandlerTask),
            eTaskGetState(irqHandlerTask));

src/irqhandler.cpp

@@ -44,11 +44,6 @@ void irqHandler(void *pvParameters) {
 // esp32 hardware timer triggered interrupt service routines
 // they notify the irq handler task
 
-void IRAM_ATTR ChannelSwitchIRQ() {
-  xTaskNotifyGive(wifiSwitchTask);
-  portYIELD_FROM_ISR();
-}
-
 void IRAM_ATTR homeCycleIRQ() {
   xTaskNotifyFromISR(irqHandlerTask, CYCLIC_IRQ, eSetBits, NULL);
   portYIELD_FROM_ISR();

src/main.cpp

@@ -27,7 +27,6 @@ Uused tasks and timers:
 
 Task          Core  Prio  Purpose
 ====================================================================================
-wifiloop      0     4     rotates wifi channels
 ledloop       0     3     blinks LEDs
 if482loop     1     3     serial feed of IF482 time telegrams
 spiloop       0     2     reads/writes data on spi interface
@@ -37,7 +36,7 @@ looptask      1     1     arduino core -> runs the LMIC LoRa stack
 irqhandler    1     1     executes tasks triggered by irq
 gpsloop       1     2     reads data from GPS via serial or i2c
 bmeloop       1     1     reads data from BME sensor via i2c
-IDLE          1     0     ESP32 arduino scheduler
+IDLE          1     0     ESP32 arduino scheduler -> runs wifi channel rotator
 
 Low priority numbers denote low priority tasks.
 
@@ -47,7 +46,7 @@ Tasks using i2c bus all must have same priority, because using mutex semaphore
 ESP32 hardware timers
 ================================
  0	triggers display refresh
- 1	triggers Wifi channel switch
+ 1  unused (reserved for DCF77)
  2	triggers send payload cycle
  3	triggers housekeeping cycle
 
@@ -67,7 +66,7 @@ uint16_t volatile macs_total = 0, macs_wifi = 0, macs_ble = 0,
                   batt_voltage = 0; // globals for display
 hw_timer_t *channelSwitch = NULL, *sendCycle = NULL, *homeCycle = NULL,
            *displaytimer = NULL; // irq tasks
-TaskHandle_t irqHandlerTask, wifiSwitchTask;
+TaskHandle_t irqHandlerTask;
 SemaphoreHandle_t I2Caccess;
 
 // container holding unique MAC address hashes with Memory Alloctor using PSRAM,
@@ -305,11 +304,6 @@ void setup() {
   timerAttachInterrupt(homeCycle, &homeCycleIRQ, true);
   timerAlarmWrite(homeCycle, HOMECYCLE * 10000, true);
 
-  // setup channel rotation trigger IRQ using esp32 hardware timer 1
-  channelSwitch = timerBegin(1, 800, true);
-  timerAttachInterrupt(channelSwitch, &ChannelSwitchIRQ, true);
-  timerAlarmWrite(channelSwitch, cfg.wifichancycle * 1000, true);
-
 // show payload encoder
 #if PAYLOAD_ENCODER == 1
   strcat_P(features, " PLAIN");
@@ -343,7 +337,7 @@ void setup() {
 #endif
 #endif
 
-  // start wifi in monitor mode and start channel rotation task on core 0
+  // start wifi in monitor mode and start channel rotation timer
   ESP_LOGI(TAG, "Starting Wifi...");
   wifi_sniffer_init();
   // initialize salt value using esp_random() called by random() in
@@ -361,16 +355,6 @@ void setup() {
                           &irqHandlerTask, // task handle
                           1);              // CPU core
 
-  // start wifi channel rotation task
-  ESP_LOGI(TAG, "Starting Wifi Channel rotation...");
-  xTaskCreatePinnedToCore(switchWifiChannel, // task function
-                          "wifiloop",        // name of task
-                          2048,              // stack size of task
-                          NULL,              // parameter of the task
-                          4,                 // priority of the task
-                          &wifiSwitchTask,   // task handle
-                          0);                // CPU core
-
 // initialize bme
 #ifdef HAS_BME
   strcat_P(features, " BME");
@@ -394,7 +378,6 @@ void setup() {
 #endif
   timerAlarmEnable(sendCycle);
   timerAlarmEnable(homeCycle);
-  timerAlarmEnable(channelSwitch);
 
 // start button interrupt
 #ifdef HAS_BUTTON

src/rcommand.cpp

@@ -67,8 +67,8 @@ void set_sendcycle(uint8_t val[]) {
 
 void set_wifichancycle(uint8_t val[]) {
   cfg.wifichancycle = val[0];
-  // update channel rotation interrupt
+  // update Wifi channel rotation timer period
-  timerAlarmWrite(channelSwitch, cfg.wifichancycle * 10000, true);
+  xTimerChangePeriod(WifiChanTimer, pdMS_TO_TICKS(cfg.wifichancycle * 10), 100 );
 
   ESP_LOGI(TAG,
            "Remote command: set Wifi channel switch interval to %.1f seconds",

src/wifiscan.cpp

@@ -7,6 +7,8 @@
 // Local logging tag
 static const char TAG[] = "wifi";
 
+TimerHandle_t WifiChanTimer;
+
 static wifi_country_t wifi_country = {WIFI_MY_COUNTRY, WIFI_CHANNEL_MIN,
                                       WIFI_CHANNEL_MAX, 100,
                                       WIFI_COUNTRY_POLICY_MANUAL};
@@ -43,10 +45,17 @@ IRAM_ATTR void wifi_sniffer_packet_handler(void *buff,
     mac_add((uint8_t *)hdr->addr2, ppkt->rx_ctrl.rssi, MAC_SNIFF_WIFI);
 }
 
+// Software-timer driven Wifi channel rotation callback function
+void switchWifiChannel(TimerHandle_t xTimer) {
+    channel =
+        (channel % WIFI_CHANNEL_MAX) + 1; // rotate channel 1..WIFI_CHANNEL_MAX
+    esp_wifi_set_channel(channel, WIFI_SECOND_CHAN_NONE);
+  }
+
 void wifi_sniffer_init(void) {
-  wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
+  wifi_init_config_t wificfg = WIFI_INIT_CONFIG_DEFAULT();
-  cfg.nvs_enable = 0;        // we don't need any wifi settings from NVRAM
+  wificfg.nvs_enable = 0;        // we don't need any wifi settings from NVRAM
-  cfg.wifi_task_core_id = 0; // we want wifi task running on core 0
+  wificfg.wifi_task_core_id = 0; // we want wifi task running on core 0
   wifi_promiscuous_filter_t filter = {
       // .filter_mask = WIFI_PROMIS_FILTER_MASK_MGMT}; // only MGMT frames
       .filter_mask = WIFI_PROMIS_FILTER_MASK_ALL}; // we use all frames
@@ -54,7 +63,7 @@ void wifi_sniffer_init(void) {
   ESP_ERROR_CHECK(esp_coex_preference_set(
       ESP_COEX_PREFER_BALANCE)); // configure Wifi/BT coexist lib
 
-  ESP_ERROR_CHECK(esp_wifi_init(&cfg)); // configure Wifi with cfg
+  ESP_ERROR_CHECK(esp_wifi_init(&wificfg)); // configure Wifi with cfg
   ESP_ERROR_CHECK(
       esp_wifi_set_country(&wifi_country)); // set locales for RF and channels
   ESP_ERROR_CHECK(
@@ -65,16 +74,11 @@ void wifi_sniffer_init(void) {
       esp_wifi_set_promiscuous_filter(&filter)); // set MAC frame filter
   ESP_ERROR_CHECK(esp_wifi_set_promiscuous_rx_cb(&wifi_sniffer_packet_handler));
   ESP_ERROR_CHECK(esp_wifi_set_promiscuous(true)); // now switch on monitor mode
-}
 
-// Wifi channel rotation task
+  // setup wifi channel rotation timer
-void switchWifiChannel(void *parameter) {
+  WifiChanTimer =
-  while (1) {
+      xTimerCreate("WifiChannelTimer", pdMS_TO_TICKS(cfg.wifichancycle * 10),
-    ulTaskNotifyTake(pdTRUE, portMAX_DELAY); // waiting for channel switch timer
+                   pdTRUE, (void *)0, switchWifiChannel);
-    channel =
+  assert(WifiChanTimer);
-        (channel % WIFI_CHANNEL_MAX) + 1; // rotate channel 1..WIFI_CHANNEL_MAX
+  xTimerStart(WifiChanTimer, 0);
-    esp_wifi_set_channel(channel, WIFI_SECOND_CHAN_NONE);
-    //ESP_LOGD(TAG, "Wifi set channel %d", channel);
-  }
-  vTaskDelete(NULL); // shoud never be reached
 }