The ESP32 supports up to four 16 MB external QSPI Flash and SRAM, with AES-based hardware encryption to protect your programs and data.
•ESP32 accesses external QSPI Flash and SRAM through cache. Up to 16 MB of external Flash is mapped into CPU code space, supporting 8-bit, 16-bit and 32-bit access, and executable code.
•Up to 8 MB of external Flash and SRAM are mapped into the CPU data space and support 8-bit, 16-bit and 32-bit accesses. Flash only supports read operations, SRAM can support read and write operations.
•The HLK-ESP32 integrates 4 MB of SPI Flash, which maps to CPU code space, supports 8-bit, 16-bit and 32-bit access and executes code. The pins GPIO6, GPIO7, GPIO8, GPIO9, GPIO10 and GPIO11 of ESP32 are used to connect the module integrated SPI Flash,Not recommended for other functions.