About use Adafruit TinyUF2 bootloader.

[water5]

I try use Adafruit TinyUF2 bootloader to install MicroPython on ESP32-S3, use https://micropython.org/resources/firmware/ESP32_GENERIC_S3-20250415-v1.25.0.uf2.
But I have no idea how to into UF2 bootloader mode after install MicroPython, CircuitPython use microcontroller.RunMode

import microcontroller

microcontroller.on_next_reset(microcontroller.RunMode.UF2)
microcontroller.reset()

[dhalbert]

Which board, exactly? Double-click the reset button, a little bit slowly, to get the ...BOOT drive.

[water5]

I use ESP32-S3 -WROOM-1 module to make minimal system, and use this firmware https://micropython.org/download/ESP32_GENERIC_S3/.

I try two ways, but not work(BOOT drive not appear),

1. Press and hold down the IO-0 Pin to GND,
   Press and release the EN Pin(reset button),
   Release the IO-0 Pin.

2. double-click reset button.

I install CircuitPython and use microcontroller.RunMode works fine.

[scruss]

But I have no idea how to into UF2 bootloader mode after install MicroPython

import machine
machine.bootloader()

[water5]

Can't into UF2 bootloader mode (BOOT drive not appear) still after machine.bootloader().

@adafruit/tinyuf2#413

[Josverl]

The S3 also supports "Touch 1200" speed toggle to enter the bootloader .

😕 Disregard the below - as I have actually never tested mpflash with that bootloader, Ill put it on the backlog ...
if you want to try , please let me know if it works.

with mpflash you can flash using :
mpflash flash --board ESP32_GENERIC_S3 --bootloader touch1200 
https://github.com/Josverl/mpflash

[scruss]

There's also this small python script that does the job:

#!/usr/bin/env python3
# reset uc on given serial port by toggling rate to 1200
# -*- coding: utf-8 -*-

import sys
import time
import serial

com = serial.Serial(sys.argv[1], 1200, dsrdtr=True)
com.dtr = False
com.rts = False
time.sleep(0.2)
com.close()
time.sleep(4)
scruss@bunny:~$ grep sys `which touch1200`
import sys
com = serial.Serial(sys.argv[1], 1200, dsrdtr=True)