|
|
|
|
.. _esp32_general:
|
|
|
|
|
|
|
|
|
|
General information about the ESP32 port
|
|
|
|
|
========================================
|
|
|
|
|
|
|
|
|
|
The ESP32 is a popular WiFi and Bluetooth enabled System-on-Chip (SoC) by
|
|
|
|
|
Espressif Systems.
|
|
|
|
|
|
|
|
|
|
Multitude of boards
|
|
|
|
|
-------------------
|
|
|
|
|
|
|
|
|
|
There is a multitude of modules and boards from different sources which carry
|
|
|
|
|
the ESP32 chip. MicroPython tries to provide a generic port which would run on
|
|
|
|
|
as many boards/modules as possible, but there may be limitations. Espressif
|
|
|
|
|
development boards are taken as reference for the port (for example, testing is
|
|
|
|
|
performed on them). For any board you are using please make sure you have a
|
|
|
|
|
datasheet, schematics and other reference materials so you can look up any
|
|
|
|
|
board-specific functions.
|
|
|
|
|
|
|
|
|
|
To make a generic ESP32 port and support as many boards as possible the
|
|
|
|
|
following design and implementation decision were made:
|
|
|
|
|
|
|
|
|
|
* GPIO pin numbering is based on ESP32 chip numbering. Please have the manual/pin
|
|
|
|
|
diagram of your board at hand to find correspondence between your board pins and
|
|
|
|
|
actual ESP32 pins.
|
|
|
|
|
* All pins are supported by MicroPython but not all are usable on any given board.
|
|
|
|
|
For example pins that are connected to external SPI flash should not be used,
|
|
|
|
|
and a board may only expose a certain selection of pins.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Technical specifications and SoC datasheets
|
|
|
|
|
-------------------------------------------
|
|
|
|
|
|
|
|
|
|
The datasheets and other reference material for ESP32 chip are available
|
|
|
|
|
from the vendor site: https://www.espressif.com/en/support/download/documents?keys=esp32 .
|
|
|
|
|
They are the primary reference for the chip technical specifications, capabilities,
|
|
|
|
|
operating modes, internal functioning, etc.
|
|
|
|
|
|
|
|
|
|
For your convenience, some of technical specifications are provided below:
|
|
|
|
|
|
|
|
|
|
* Architecture: Xtensa Dual-Core 32-bit LX6
|
|
|
|
|
* CPU frequency: up to 240MHz
|
|
|
|
|
* Total RAM available: 528KB (part of it reserved for system)
|
|
|
|
|
* BootROM: 448KB
|
|
|
|
|
* Internal FlashROM: none
|
|
|
|
|
* External FlashROM: code and data, via SPI Flash; usual size 4MB
|
|
|
|
|
* GPIO: 34 (GPIOs are multiplexed with other functions, including
|
|
|
|
|
external FlashROM, UART, etc.)
|
|
|
|
|
* UART: 3 RX/TX UART (no hardware handshaking), one TX-only UART
|
|
|
|
|
* SPI: 4 SPI interfaces (one used for FlashROM)
|
|
|
|
|
* I2C: 2 I2C (bitbang implementation available on any pins)
|
|
|
|
|
* I2S: 2
|
|
|
|
|
* ADC: 12-bit SAR ADC up to 18 channels
|
|
|
|
|
* DAC: 2 8-bit DACs
|
|
|
|
|
* RMT: 8 channels allowing accurate pulse transmit/receive
|
|
|
|
|
* Programming: using BootROM bootloader from UART - due to external FlashROM
|
|
|
|
|
and always-available BootROM bootloader, the ESP32 is not brickable
|
|
|
|
|
|
|
|
|
|
For more information see the ESP32 datasheet: https://www.espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf
|
|
|
|
|
|
|
|
|
|
MicroPython is implemented on top of the ESP-IDF, Espressif's development
|
|
|
|
|
framework for the ESP32. This is a FreeRTOS based system. See the
|
|
|
|
|
`ESP-IDF Programming Guide <https://docs.espressif.com/projects/esp-idf/en/latest/index.html>`_
|
|
|
|
|
for details.
|
