2019-01-21 21:06:17 +00:00
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.. _esp32_general:
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General information about the ESP32 port
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========================================
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The ESP32 is a popular WiFi and Bluetooth enabled System-on-Chip (SoC) by
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Espressif Systems.
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Multitude of boards
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There is a multitude of modules and boards from different sources which carry
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the ESP32 chip. MicroPython tries to provide a generic port which would run on
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as many boards/modules as possible, but there may be limitations. Espressif
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development boards are taken as reference for the port (for example, testing is
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performed on them). For any board you are using please make sure you have a
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datasheet, schematics and other reference materials so you can look up any
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board-specific functions.
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To make a generic ESP32 port and support as many boards as possible the
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following design and implementation decision were made:
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* GPIO pin numbering is based on ESP32 chip numbering. Please have the manual/pin
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diagram of your board at hand to find correspondence between your board pins and
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actual ESP32 pins.
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* All pins are supported by MicroPython but not all are usable on any given board.
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For example pins that are connected to external SPI flash should not be used,
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and a board may only expose a certain selection of pins.
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Technical specifications and SoC datasheets
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The datasheets and other reference material for ESP32 chip are available
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from the vendor site: https://www.espressif.com/en/support/download/documents?keys=esp32 .
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They are the primary reference for the chip technical specifications, capabilities,
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operating modes, internal functioning, etc.
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For your convenience, some of technical specifications are provided below:
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* Architecture: Xtensa Dual-Core 32-bit LX6
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* CPU frequency: up to 240MHz
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* Total RAM available: 528KB (part of it reserved for system)
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* BootROM: 448KB
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* Internal FlashROM: none
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* External FlashROM: code and data, via SPI Flash; usual size 4MB
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* GPIO: 34 (GPIOs are multiplexed with other functions, including
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external FlashROM, UART, etc.)
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* UART: 3 RX/TX UART (no hardware handshaking), one TX-only UART
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* SPI: 4 SPI interfaces (one used for FlashROM)
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* I2C: 2 I2C (bitbang implementation available on any pins)
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* I2S: 2
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* ADC: 12-bit SAR ADC up to 18 channels
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* DAC: 2 8-bit DACs
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2019-09-29 14:36:22 +01:00
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* RMT: 8 channels allowing accurate pulse transmit/receive
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2019-01-21 21:06:17 +00:00
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* Programming: using BootROM bootloader from UART - due to external FlashROM
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and always-available BootROM bootloader, the ESP32 is not brickable
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For more information see the ESP32 datasheet: https://www.espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf
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MicroPython is implemented on top of the ESP-IDF, Espressif's development
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framework for the ESP32. This is a FreeRTOS based system. See the
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`ESP-IDF Programming Guide <https://docs.espressif.com/projects/esp-idf/en/latest/index.html>`_
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for details.
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