Add Deep Sleep workaround example for counterfeit ESP8266 devices

esp8266/Arduino#6007

examples/Processors/ESP8266/DeepSleep/ESP8266_Deep_Sleep_Workaround/ESP8266_Deep_Sleep_Workaround.ino

@@ -0,0 +1,74 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 Erriez
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*!
+ * \brief Erriez ESP8266 deepSleep() workaround
+ * \details
+ *      deepSleep() does not wake up correctly on some counterfeit ESP8266.
+ *      A workaround is created on GitHub, unfortunately without documentation:
+ *          https://github.com/esp8266/Arduino/issues/6007
+ *      Note: Use ESP.deepSleep() for genuine ESP8266 devices.
+ *
+ *      Source:         https://github.com/Erriez/ErriezArduinoExamples
+ */
+
+#include "ESP8266WiFi.h"
+extern "C" {
+#include <user_interface.h>
+}
+
+#define ets_wdt_disable ((void (*)(void))0x400030f0)
+#define ets_delay_us ((void (*)(int))0x40002ecc)
+
+#define _R (uint32_t *)0x60000700
+
+
+void nk_deep_sleep(uint64_t time)
+{
+    ets_wdt_disable();
+    *(_R + 4) = 0;
+    *(_R + 17) = 4;
+    *(_R + 1) = *(_R + 7) + 5;
+    *(_R + 6) = 8;
+    *(_R + 2) = 1 << 20;
+    ets_delay_us(10);
+    *(_R + 39) = 0x11;
+    *(_R + 40) = 3;
+    *(_R) &= 0xFCF;
+    *(_R + 1) = *(_R + 7) + (45*(time >> 8));
+    *(_R + 16) = 0x7F;
+    *(_R + 2) = 1 << 20;
+    __asm volatile ("waiti 0");
+}
+
+void setup()
+{
+    delay(1000);
+
+    nk_deep_sleep(2000000);
+}
+
+void loop()
+{
+}