Merge pull request #35 from brentru/add-esp8266

Add ESP8266 Support

Adafruit_SleepyDog.cpp

@@ -20,6 +20,8 @@
  * You can restore the USB serial connection after waking up using
  * `USBDevice.attach();` and then reconnect to USB serial from the host machine.
  * Partial support for Teensy 3.X and LC (watchdog, no sleep).
+ * ESP32/ESP32-S2
+ * ESP8266
  *
  * Adafruit Trinket and other boards using ATtiny MCUs are NOT supported.
  */

Adafruit_SleepyDog.h

@@ -31,6 +31,9 @@ typedef WatchdogNRF WatchdogType;
 #elif defined(ARDUINO_ARCH_ESP32)
 #include "utility/WatchdogESP32.h"
 typedef WatchdogESP32 WatchdogType;
+#elif defined(ARDUINO_ARCH_ESP8266)
+#include "utility/WatchdogESP8266.h"
+typedef WatchdogESP8266 WatchdogType;
 #else
 #error Unsupported platform for the Adafruit Watchdog library!
 #endif

README.md

@@ -12,3 +12,5 @@ Currently supports the following hardware:
 *  Partial support for Teensy 3.X and LC (watchdog, no sleep).
 *  ATtiny 24/44/84 and 25/45/85
 *  ESP32, ESP32-S2
+*  ESP8266 WITH CAVEAT: The software and hardware watchdog timers are fixed to specific
+intervals and not programmable. Notes about this are within the `utility/WatchdogESP8266.cpp` file.

examples/BasicUsage/BasicUsage.ino

@@ -8,7 +8,8 @@
 
 void setup() {
   Serial.begin(115200);
-  while(!Serial) delay(10); 
+  while (!Serial)
+    delay(10);
   // wait for Arduino Serial Monitor (native USB boards)
 
   Serial.println("Adafruit Watchdog Library Demo!");
@@ -29,8 +30,9 @@ void setup() {
 
   // Now loop a few times and periodically reset the watchdog.
   Serial.println("Looping ten times while resetting the watchdog...");
-  for(int i = 1; i <= 10; ++i) {
-    Serial.print("Loop #"); Serial.println(i, DEC);
+  for (int i = 1; i <= 10; ++i) {
+    Serial.print("Loop #");
+    Serial.println(i, DEC);
     delay(1000);
     // Reset watchdog with every loop to make sure the sketch keeps running.
     // If you comment out this call watch what happens in about 4 iterations!
@@ -41,7 +43,7 @@ void setup() {
 #ifndef NRF52_SERIES // cannot disable nRF's WDT
   // Disable the watchdog entirely by calling Watchdog.disable();
   Watchdog.disable();
-#endif  
+#endif
 
   // Finally demonstrate the watchdog resetting by enabling it for a shorter
   // period of time and waiting a long time without a reset.  Notice you can
@@ -54,7 +56,13 @@ void setup() {
   Serial.print(countdownMS, DEC);
   Serial.println(" milliseconds!");
   Serial.println();
-  delay(countdownMS+1000);
+#ifndef ARDUINO_ARCH_ESP8266
+  delay(countdownMS + 1000);
+#else
+  // Calls to delay() and yield() feed the ESP8266's
+  // hardware and software watchdog timers, delayMicroseconds does not.
+  delayMicroseconds(countdownMS * 1000);
+#endif
 
   // Execution will never get here because the watchdog resets the Arduino!
 }

library.properties

@@ -1,9 +1,9 @@
 name=Adafruit SleepyDog Library
-version=1.5.0
+version=1.6.0
 author=Adafruit
 maintainer=Adafruit <[email protected]>
 sentence=Arduino library to use the watchdog timer for system reset and low power sleep.
 paragraph=Arduino library to use the watchdog timer for system reset and low power sleep.
 category=Other
 url=https://github.com/adafruit/Adafruit_SleepyDog
-architectures=avr,samd,nrf52,teensy, esp32
+architectures=avr,samd,nrf52,teensy,esp32,esp8266

utility/WatchdogESP8266.cpp

@@ -0,0 +1,76 @@
+#if defined(ARDUINO_ARCH_ESP8266)
+
+#include "WatchdogESP8266.h"
+
+/**********************************************************************************************/
+/*!
+    @brief  Initializes the ESP8266's software WDT
+    @param    maxPeriodMS
+              Timeout period of WDT in milliseconds
+    @return The actual period (in milliseconds) before a watchdog timer
+            reset is returned, 0 otherwise.
+    NOTE: Configuring the software WDT timeout maxPeriodMS value is NOT
+   IMPLEMENTED in the ESP8266 BSP [1]. Further, an investigation into the
+   default software WDT time yielded a fixed timeout period of 3.2 seconds [2].
+    [1] https://github.com/esp8266/Arduino/blob/master/cores/esp8266/Esp.h#L91
+    [2]https://sigmdel.ca/michel/program/esp8266/arduino/watchdogs_en.html#ESP8266_WDT_TIMEOUT
+*/
+/**********************************************************************************************/
+int WatchdogESP8266::enable(int maxPeriodMS) {
+  if (maxPeriodMS < 0)
+    return 0;
+
+  // Enable the WDT
+  ESP.wdtEnable(0);
+
+  _wdto = maxPeriodMS;
+  return maxPeriodMS;
+}
+
+/**************************************************************************/
+/*!
+    @brief  Feeds the Watchdog timer.
+    NOTE: Calling yield() or delay() also feeds the hardware and software
+    watchdog timers.
+*/
+/**************************************************************************/
+void WatchdogESP8266::reset() { ESP.wdtFeed(); }
+
+/**************************************************************************/
+/*!
+    @brief  Disables the Watchdog Timer.
+        NOTE: Please don't stop the software WDT too long
+        (less than 6 seconds), otherwise it will trigger a hardware
+        watchdog reset!
+*/
+/**************************************************************************/
+void WatchdogESP8266::disable() { ESP.wdtDisable(); }
+
+/**************************************************************************/
+/*!
+    @brief  Configures the ESP8266 to enter a low-power sleep mode for a
+            desired amount of time.
+    @param    maxPeriodMS
+              Time to sleep the ESP8266, in millis.
+    @return The actual period (in milliseconds) that the hardware was
+            asleep will be returned. Otherwise, 0 will be returned if the
+            hardware could not enter the low-power mode.
+*/
+/**************************************************************************/
+int WatchdogESP8266::sleep(int maxPeriodMS) {
+  if (maxPeriodMS < 0)
+    return 0;
+  // Convert from MS to microseconds
+  uint64_t sleepTime = maxPeriodMS * 1000;
+
+  // Assert that we can not sleep longer than the max. time calculated by ESP
+  if (sleepTime > ESP.deepSleepMax())
+    return 0;
+
+  // Enters deep sleep with mode WAKE_RF_DEFAULT
+  ESP.deepSleep(sleepTime);
+
+  return maxPeriodMS;
+}
+
+#endif // ARDUINO_ARCH_ESP8266

utility/WatchdogESP8266.h

@@ -0,0 +1,40 @@
+/*!
+ * @file WatchdogESP8266.h
+ *
+ * Support for ESP8266 WDT and low-power sleep modes.
+ *
+ * Adafruit invests time and resources providing this open source code,
+ * please support Adafruit and open-source hardware by purchasing
+ * products from Adafruit!
+ *
+ * Written by Brent Rubell for Adafruit Industries.
+ *
+ * MIT License, all text here must be included in any redistribution.
+ *
+ */
+#ifndef WATCHDOGESP8266_H_
+#define WATCHDOGESP8266_H_
+
+// #include "esp_sleep.h"
+// #include "esp_task_wdt.h"
+#include "Esp.h"
+
+/**************************************************************************/
+/*!
+    @brief  Class that contains functions for interacting with the
+            ESP8266's WDT and low-power sleep functions.
+*/
+/**************************************************************************/
+class WatchdogESP8266 {
+public:
+  WatchdogESP8266() : _wdto(-1){};
+  int enable(int maxPeriodMS = 0);
+  void reset();
+  void disable();
+  int sleep(int maxPeriodMS = 0);
+
+private:
+  int _wdto;
+};
+
+#endif // WATCHDOGESP8266_H