Espressif Systems ESP32-WROVER-E User Manual page 9

3. Functional Description
3. Functional Description
This chapter describes the modules and functions integrated in ESP32-WROVER-E.
3.1 CPU and Internal Memory
ESP32-D0WD-V3 contains two low-power Xtensa
includes:
• 448 KB of ROM for booting and core functions.
• 520 KB of on-chip SRAM for data and instructions.
• 8 KB of SRAM in RTC, which is called RTC FAST Memory and can be used for data storage; it is
accessed by the main CPU during RTC Boot from the Deep-sleep mode.
• 8 KB of SRAM in RTC, which is called RTC SLOW Memory and can be accessed by the co-processor
during the Deep-sleep mode.
• 1 Kbit of eFuse: 256 bits are used for the system (MAC address and chip configuration) and the
remaining 768 bits are reserved for customer applications, including flash-encryption and chip-ID.
3.2 External Flash and SRAM
ESP32 supports multiple external QSPI flash and SRAM chips. More details can be found in Chapter SPI in
the ESP32 Technical Reference
AES to pro-tect developers' programs and data in flash.
ESP32 can access the external QSPI flash and SRAM through high-speed caches.
• The external flash can be mapped into CPU instruction memory space and read-only memory space
simul-taneously.
– When external flash is mapped into CPU instruction memory space, up to 11 MB + 248 KB can be
mapped at a time. Note that if more than 3 MB + 248 KB are mapped, cache performance will be
reduced due to speculative reads by the CPU.
– When external flash is mapped into read-only data memory space, up to 4 MB can be mapped at a
time. 8-bit, 16-bit and 32-bit reads are supported.
• External SRAM can be mapped into CPU data memory space. Up to 4 MB can be mapped at a time. 8-
bit, 16-bit and 32-bit reads and writes are supported.
ESP32-WROVER-E integrates a 8 MB SPI flash and an 8 MB PSRAM for more memory space.
3.3 Crystal Oscillators
The module uses a 40-MHz crystal oscillator.
®
32-bit LX6 microprocessors. The internal memory
Manual. ESP32 also supports hardware encryption/decryption based on
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