Boards

The boards that run Frothy, how each one connects, and the boards that do not work.

Frothy has official firmware for seven boards. Install it once with the browser flasher . Then program the board in the browser editor .

Board	Chip	USB connection	`$led_builtin`	Radio
ESP32 DevKit V1	ESP32	USB-to-UART chip	LED pin	Wi-Fi, Bluetooth LE
NodeMCU ESP-32S	ESP32	USB-to-UART chip	`nil`	Wi-Fi, Bluetooth LE
Seeed Studio XIAO ESP32C3	ESP32-C3	USB Serial/JTAG	`nil`	Wi-Fi, Bluetooth LE
Seeed Studio XIAO ESP32C6	ESP32-C6	USB Serial/JTAG	LED pin	Wi-Fi, Bluetooth LE
Seeed Studio XIAO ESP32S3	ESP32-S3	USB Serial/JTAG	LED pin	Wi-Fi, Bluetooth LE
Seeed Studio XIAO RP2040	RP2040	native USB	LED pin	none
Arduino Nano RP2040 Connect	RP2040	native USB	LED pin	Wi-Fi, Bluetooth LE

All seven boards have $a0, $sda and $scl, and the ESP32 boards also have $boot_button. Use these names, not pin numbers, and the same program runs on more than one board. When $led_builtin is nil, the led.* words stop with an error. Connect an LED to a pin, and use gpio.write: pin, 1.

The pins of these boards use 3.3 V. Do not connect a 5 V signal to a pin.

ESP32 Boards

The flasher writes Frothy to an ESP32 board over USB. If it cannot connect, start the board in download mode, as Install shows.

When an ESP32 board starts, it prints boot: Ctrl-C or BOOT skips saved code. Press Ctrl-C or the BOOT button in the next 600 ms, and the board starts without your saved program. Use this when your saved program does not let the prompt appear.

The DevKit V1 and the NodeMCU ESP-32S connect through a USB-to-UART chip, CP210x or CH340. On some computers, this chip needs a driver.

The XIAO ESP32C3, ESP32C6 and ESP32S3 connect through the USB Serial/JTAG unit in the chip. This connection has no flow control. When you paste more than about 1 KB into a terminal or frothy connect, the board can lose bytes with no error. The editor and frothy send wait for the prompt after each form, so they do not send too much at one time.

The XIAO ESP32C3 has no trace.* words.

RP2040 Boards

For an RP2040 board, the flasher downloads a UF2 file. Restart the board in BOOTSEL mode, and drag the file to the RPI-RP2 drive. The flasher can restart the board in BOOTSEL mode over USB. If the drive does not appear:

XIAO RP2040: hold BOOT, press and release RESET, then release BOOT.
Nano RP2040 Connect: with USB connected, connect REC to GND and press RESET. Remove the jumper when the RPI-RP2 drive appears.

An RP2040 board has no safe-boot window. Press Ctrl-C to stop a boot word that does not end.

RP2040 boards do not have the uart.*, trace.*, pulse.*, sleep.* and watchdog.* words, or console.uart, console.default and console.info. The Nano RP2040 Connect has the Wi-Fi, HTTP and TCP words. Its Bluetooth words scan and advertise, but they do not connect. The XIAO RP2040 has no radio words. RP2040 boards also have smaller tables. See Limits .

Boards That Do Not Work

Frothy has no firmware for the Arduino UNO, UNO R4, Nano, Nano Every, Nano 33 IoT or Nano R4. Their chips are not ESP32 or RP2040 chips. The Arduino Nano ESP32 has an ESP32-S3 chip, but it has no official Frothy firmware yet.