ESP8266 Peripherals and Interfacing
1.SPI Flash Memory Operations
The flash memory connected to the ESP8266 stores code and user data. This main flash memory chip is called as the primary flash memory chip. There may be more external SPI flash chips connected to the HSPI interface of the ESP8266 for data storage purposes and they are not covered in this section. The primary external flash memory chip with the ESP8266 supports the following operations using the SDK APIs provided by Espressif Systems.
1.1.Read SPI flash ID
The flash chip ID may be read using the API