add functions to read out the flash config

Serial.print(F("Flash Chip Size: "));
Serial.println(ESP.getFlashChipSize());

Serial.print(F("Flash Chip Speed: "));
Serial.println(ESP.getFlashChipSpeed());

Serial.print(F("Flash Chip Mode: 0x"));
Serial.println(ESP.getFlashChipMode(), HEX);

cores/esp8266/Arduino.h

@@ -82,6 +82,18 @@ void yield(void);
 #define degrees(rad) ((rad)*RAD_TO_DEG)
 #define sq(x) ((x)*(x))
 
+#define kHz (1000L)
+#define MHz (1000L*kHz)
+#define GHz (1000L*MHz)
+
+#define kBit (1024L)
+#define MBit (1024L*kBit)
+#define GBit (1024L*kBit)
+
+#define kB (1024L)
+#define MB (1024L*kB)
+#define GB (1024L*MB)
+
 void ets_intr_lock();
 void ets_intr_unlock();
 

cores/esp8266/Esp.cpp

@@ -89,11 +89,6 @@ uint32_t EspClass::getChipId(void)
     return system_get_chip_id();
 }
 
-uint32_t EspClass::getFlashChipId(void)
-{
-    return spi_flash_get_id();
-}
-
 const char * EspClass::getSDKversion(void)
 {
     return system_get_sdk_version();
@@ -113,3 +108,70 @@ uint8_t EspClass::getCPUfreqMHz(void)
 {
     return system_get_cpu_freq();
 }
+
+
+uint32_t EspClass::getFlashChipId(void)
+{
+    return spi_flash_get_id();
+}
+
+uint32_t EspClass::getFlashChipSize(void)
+{
+    uint32_t data;
+    uint8_t * bytes = (uint8_t *) &data;
+    // read first 4 byte (magic byte + flash config)
+    if(spi_flash_read(0x0000, &data, 4) == SPI_FLASH_RESULT_OK) {
+        switch((bytes[3] & 0xF0) >> 4) {
+            case 0x0: // 4 Mbit (512KB)
+                return (512 * kB);
+            case 0x1: // 2 MBit (256KB)
+                return (256 * kB);
+            case 0x2: // 8 MBit (1MB)
+                return (1 * MB);
+            case 0x3: // 16 MBit (2MB)
+                return (2 * MB);
+            case 0x4: // 32 MBit (4MB)
+                return (4 * MB);
+            default: // fail?
+                return 0;
+        }
+    }
+    return 0;
+}
+
+uint32_t EspClass::getFlashChipSpeed(void)
+{
+    uint32_t data;
+    uint8_t * bytes = (uint8_t *) &data;
+    // read first 4 byte (magic byte + flash config)
+    if(spi_flash_read(0x0000, &data, 4) == SPI_FLASH_RESULT_OK) {
+        switch(bytes[3] & 0x0F) {
+            case 0x0: // 40 MHz
+                return (40 * MHz);
+            case 0x1: // 26 MHz
+                return (26 * MHz);
+            case 0x2: // 20 MHz
+                return (20 * MHz);
+            case 0xF: // 80 MHz
+                return (80 * MHz);
+            default: // fail?
+                return 0;
+        }
+    }
+    return 0;
+}
+
+FlashMode_t EspClass::getFlashChipMode(void)
+{
+    FlashMode_t mode = FM_FAILD;
+    uint32_t data;
+    uint8_t * bytes = (uint8_t *) &data;
+    // read first 4 byte (magic byte + flash config)
+    if(spi_flash_read(0x0000, &data, 4) == SPI_FLASH_RESULT_OK) {
+        mode = (FlashMode_t) bytes[2];
+        if(mode > FM_DOUT) {
+            mode = FM_FAILD;
+        }
+    }
+    return mode;
+}

cores/esp8266/Esp.h

@@ -49,6 +49,14 @@ enum WakeMode {
     WAKE_RF_DISABLED = 4 // disable RF after deep-sleep wake up, just like modem sleep, there will be the smallest current.
 };
 
+typedef enum {
+     FM_QIO = 0x00,
+     FM_QOUT = 0x01,
+     FM_DIO = 0x02,
+     FM_DOUT = 0x03,
+     FM_FAILD = 0xFF
+} FlashMode_t;
+
 class EspClass {
     public:
         EspClass();
@@ -69,7 +77,7 @@ class EspClass {
         uint32_t getFreeHeap(void);
 
         uint32_t getChipId(void);
-        uint32_t getFlashChipId(void);
+
 
         const char * getSDKversion(void);
 
@@ -78,6 +86,11 @@ class EspClass {
 
         uint8_t getCPUfreqMHz(void);
 
+        uint32_t getFlashChipId(void);
+        uint32_t getFlashChipSize(void);
+        uint32_t getFlashChipSpeed(void);
+        FlashMode_t getFlashChipMode(void);
+
 };
 
 extern EspClass ESP;