Data Sheet

3. FUNCTIONAL DESCRIPTION
3. Functional Description
This chapter describes the modules and functions integrated in ESP32-WROVER.
3.1 CPU and Internal Memory
ESP32-D0WDQ6 contains two low-power Xtensa
®
32-bit LX6 microprocessors. The internal memory includes:
• 448 kB of ROM for booting and core functions.
• 520 kB (8 kB RTC FAST Memory included) of on-chip SRAM for data and instruction.
– 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, of which 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 up to four 16-MB of external QSPI flash and SRAM with hardware encryption based on AES to
protect developers’ programs and data.
ESP32 can access the external QSPI flash and SRAM through high-speed caches.
• Up to 16 MB of external flash are memory-mapped onto the CPU code space, supporting 8, 16 and 32-bit
access. Code execution is supported.
• Up to 8 MB of external flash/SRAM are memory-mapped onto the CPU data space, supporting 8, 16 and
32-bit access. Data-read is supported on the flash and SRAM. Data-write is supported on the SRAM.
ESP32-WROVER integrates 4 MB of external SPI flash. The 4-MB SPI flash can be memory-mapped onto the
CPU code space, supporting 8, 16 and 32-bit access. Code execution is supported.
In addition to the 4 MB SPI flash, ESP32-WROVER also integrates 4 MB PSRAM for more memory space.
3.3 Crystal Oscillators
The ESP32 Wi-Fi/BT firmware can only support 40 MHz crystal oscillator for now.
Espressif Systems 7 ESP32-WROVER Datasheet V1.2