ESP32
doit esp32 dev kit v1 921600 80Mhz
Espressif
https://www.esp32.com/viewforum.php?f=23
ESP8266
https://github.com/SmartArduino/SZDOITWiKi/wiki/ESP8266---ESP32
ESP32
DOIT Esp32 DevKit v1 ESP-WROOM32 Xtensa LX6
Arduino
Platform.io
921600 80Mhz
https://docs.platformio.org/en/latest/boards/espressif32/esp32doit-devkit-v1.html
RTOS
FreeRTOS
https://github.com/FreeRTOS/FreeRTOS-Kernel
ZephyrOS
Thread
https://www.espressif.com/en/news/ESP32_H2
ESP32-H2 Risc V Thread, Zigbee, Bluetooth LE
ESP32-S3
https://openthread.io/guides/border-router/espressif-esp32
https://github.com/Ebiroll/qemu_esp32
QSPI
Python39\Scripts\esptool.exe read_flash --spi-connection HSPI 0 0x400000 flash_dump.bin
esptool.py v3.0 Found 1 serial ports Serial port COM3 Connecting.... Detecting chip type... ESP32 Chip is ESP32-D0WDQ6 (revision 1) Features: WiFi, BT, Dual Core, 240MHz, VRef calibration in efuse, Coding Scheme None Crystal is 40MHz MAC: 24:6f:28:24:22:2c Uploading stub... Running stub... Stub running... Configuring SPI flash mode... 4194304 (100 %) 4194304 (100 %) Read 4194304 bytes at 0x0 in 379.9 seconds (88.3 kbit/s)... Hard resetting via RTS pin...
https://github.com/espressif/esp-idf/tree/master/components/spi_flash
https://my-esp-idf.readthedocs.io/en/latest/api-reference/peripherals/spi_master.html https://github.com/espressif/arduino-esp32/blob/master/tools/sdk/include/esp32/rom/spi_flash.h ESP32 chip have 4 SPI slave/master SPI0, SPI1, HSPI and VSPI. SPI0 is used as an SPI master to access Flash and ext-SRAM SPI1 is connected to the same hardware lines as SPI0 HSPI and VSPI all have three chip select lines
use 40M clock SPI Flash can use 2 lines or 4 lines mode. If you use 2 lines mode, you can save two pad SPIHD and SPIWP for gpio. Common SPI command to configure Flash to QIO mode
miso - Also known as q, this is the input of the serial stream into the ESP32 mosi - Also known as d, this is the output of the serial stream from the ESP32 sclk - Clock signal. Each data bit is clocked out or in on the positive or negative edge of this signal quadwp - Write Protect signal. Only used for 4-bit (qio/qout) transactions. quadhd - Hold signal. Only used for 4-bit (qio/qout) transactions.
In master mode SPID = MOSI = data out SPIQ = MISO = data in
https://drive.google.com/file/d/11-IH-38VJOXbFJ1ybB1i2Cvcl9n3pSTU/view
SPI.begin SPI.setBitOrder SPI.setClockDivider SPI.setDataMode SPI.transfer
spi_bus_initialize
https://github.com/espressif/esptool/wiki/SPI-Flash-Modes
https://github.com/espressif/esptool#read-spi-flash-id
Particle Xenon
https://docs.particle.io/xenon/
\.platformio\packages\framework-espidf\components\esptool_py
https://docs.platformio.org/en/latest/frameworks/zephyr.html#framework-zephyr