ESP32 Hosted

ESP32 Hosted (ESP-Hosted-MCU) is a solution that allows you to use ESP32 modules as communication co-processors. This solution provides wireless connectivity (Wi-Fi and Bluetooth) to the host module, enabling it to communicate with other devices.

Two transport modes are supported: SDIO (default) and SPI.

SDIO Transport

# Example SDIO configuration (4-bit, default)
esp32_hosted:
  type: sdio
  variant: ESP32C6
  reset_pin: GPIOXX
  cmd_pin: GPIOXX
  clk_pin: GPIOXX
  d0_pin: GPIOXX
  d1_pin: GPIOXX
  d2_pin: GPIOXX
  d3_pin: GPIOXX
  active_high: true
  sdio_frequency: 10MHz

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

# Example SDIO configuration (1-bit)
esp32_hosted:
  type: sdio
  variant: ESP32C6
  bus_width: 1
  reset_pin: GPIOXX
  cmd_pin: GPIOXX
  clk_pin: GPIOXX
  d0_pin: GPIOXX
  active_high: true

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

SDIO Configuration variables

type (Optional, string): The transport mode. Set to sdio for SDIO transport. Defaults to sdio.
variant (Required, string): The variant of the ESP32 co-processor that is used by the host. One of ESP32, ESP32S2, ESP32S3, ESP32C2, ESP32C3 and ESP32C6.
reset_pin (Required, Pin): The reset pin of the co-processor.
active_high (Required, boolean): If enabled, the co-processor is active when reset is high. If disabled, the co-processor is active when reset is low.
clk_pin (Required, Pin): The SDIO clock pin.
cmd_pin (Required, Pin): The SDIO command pin.
d0_pin (Required, Pin): The SDIO D0 pin.
d1_pin (Optional, Pin): The SDIO D1 pin. Required when bus_width is 4.
d2_pin (Optional, Pin): The SDIO D2 pin. Required when bus_width is 4.
d3_pin (Optional, Pin): The SDIO D3 pin. Required when bus_width is 4.
bus_width (Optional, int): The SDIO bus width. Either 1 or 4. Defaults to 4.
slot (Optional, int): The SDIO slot number. Defaults to 1.
sdio_frequency (Optional, frequency): Set the speed of communication between the host and the co-processor. If you experience loss of communication, or reboots, then try reducing this value. The value can be between 400kHz and 50MHz, with a default of 40MHz.

SPI Transport

# Example SPI configuration
esp32_hosted:
  type: spi
  variant: ESP32C6
  reset_pin: GPIOXX
  clk_pin: GPIOXX
  mosi_pin: GPIOXX
  miso_pin: GPIOXX
  cs_pin: GPIOXX
  handshake_pin: GPIOXX
  data_ready_pin: GPIOXX
  active_high: true

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

SPI Configuration variables

type (Required, string): The transport mode. Set to spi for SPI transport.
variant (Required, string): The variant of the ESP32 co-processor that is used by the host. One of ESP32, ESP32S2, ESP32S3, ESP32C2, ESP32C3 and ESP32C6.
reset_pin (Required, Pin): The reset pin of the co-processor.
active_high (Required, boolean): If enabled, the co-processor is active when reset is high. If disabled, the co-processor is active when reset is low.
clk_pin (Required, Pin): The SPI clock pin.
mosi_pin (Required, Pin): The SPI MOSI pin.
miso_pin (Required, Pin): The SPI MISO pin.
cs_pin (Required, Pin): The SPI chip select pin.
handshake_pin (Required, Pin): The handshake pin used by the co-processor to signal readiness.
data_ready_pin (Required, Pin): The data ready pin used by the co-processor to signal available data.
spi_mode (Optional, int): The SPI mode (0-3). Defaults depend on the variant: mode 2 for ESP32, mode 3 for all others.
frequency (Optional, frequency): The SPI clock frequency. Maximum depends on variant: 10MHz for ESP32, 40MHz for all other variants. Defaults to the maximum for each variant.
handshake_active_high (Optional, boolean): Polarity of the handshake signal. Defaults to true.
data_ready_active_high (Optional, boolean): Polarity of the data ready signal. Defaults to true.

Updating co-processor firmware