Blinky ESP32-S3 with Micropython

Updated on 19 November 2022

dev board ESP32-S3-DevKitC-1

chip ESP32-S3-WROOM-1-N8R2

features blinky led esp32s3 micropython ampy

This tutorial is more than 1 year old. If the steps below do not work, then please check the latest versions and the documentations of the individual tools used.

Before starting

Dependancies

Ensure the following dependancies are downloaded and available:

Buy the components

ESP32-S3-DevKitC-1-N8R2

Code

Download code blink.py

from machine import Pin
import time
led_pin = 5  # Default on-board RGB LED GPIO48 does not work

led = Pin(led_pin, Pin.OUT)
for i in range(10):
  led.on()
  time.sleep_ms(500)
  led.off()
  time.sleep_ms(500)
  print("Blink ", i+1)

Makefile

PYTHON_FILE=blink.py
BIN_FILENAME=GENERIC_S3-20220618-v1.19.1.bin
UPLOAD_PORT?=/dev/cu.usbmodem14*
SERIAL_PORT?=/dev/cu.usbserial-14*

.PHONY: help default upload log

default: upload

help: ## Show help message
	@awk 'BEGIN {FS = ":.*##"; printf "\nUsage:\n  make \033[36m\033[0m\n"} /^[$$()% 0-9a-zA-Z_-]+:.*?##/ { printf "  \033[36m%-15s\033[0m %s\n", $$1, $$2 } /^##@/ { printf "\n\033[1m%s\033[0m\n", substr($$0, 5) } ' $(MAKEFILE_LIST)

upload: ## Erase flash and then upload the micropython binary
	@echo "Ensure you plug in the board into the USB port"
	@ls /dev/cu.*
	esptool.py --chip esp32s3 --port $(UPLOAD_PORT) erase_flash
	esptool.py --chip esp32s3 --port $(UPLOAD_PORT) write_flash -z 0 $(BIN_FILENAME)

log: ## Access the serial monitor with ampy
	@ls /dev/cu.*
	@echo "Ensure you plug in the board into the UART port"
	ampy --port $(SERIAL_PORT) run $(PYTHON_FILE)

rollback:
	@ls /dev/cu.*
	@echo "Ensure you plug in the board into the UART port"
	esptool.py --port $(SERIAL_PORT) erase_flash
	@echo "Flash in ESP-IDF blinky"

Prototype

A photo of the actual setup.

Schematic

Wire up the hardware accordingly

Serial console

Serial output from the firmware.

Blinky ESP32-S3 with Micropython browser

Use GPIO5 to add a simple external LED

Description

LED

The default on-board RGB LED GPIO48 does not work with the blinky code. Hence, wire up a simple LED and resistor to GPIO5 of the board.

Upload Micropython binary

Plug in the board via the USB port to know the port number

 $ ls /dev/cu.*

 /dev/cu.Bluetooth-Incoming-Port  /dev/cu.usbmodem14101

Download the *.bin file for the board GENERIC_S3-20220618-v1.19.1.bin

Erase the entire flash

 $ esptool.py --chip esp32s3 --port /dev/cu.usbmodem14101 erase_flash

 esptool.py v4.3
 Serial port /dev/cu.usbmodem14101
 Connecting...
 Chip is ESP32-S3 (revision v0.1)
 Features: WiFi, BLE
 Crystal is 40MHz
 MAC: 7c:df:a1:e2:79:08
 Uploading stub...
 Running stub...
 Stub running...
 Erasing flash (this may take a while)...
 Chip erase completed successfully in 21.5s
 Hard resetting via RTS pin...

Flash the firmware starting at address 0

 $ esptool.py --chip esp32s3 --port /dev/cu.usbmodem14101 write_flash -z 0 GENERIC_S3-20220618-v1.19.1.bin

Access the Serial monitor with the Python code

Download ampy and ensure it is available
```
 ampy --help
```
Plug in the board through the UART port

Check the port number of the board

 ls /dev/cu.*

 /dev/cu.Bluetooth-Incoming-Port  /dev/cu.SLAB_USBtoUART  /dev/cu.usbserial-1410

Run the python script

 ampy --port /dev/cu.usbserial-1410 run blink.py

Rollback from Micropython to Arduino

Follow the rollback steps to erase the flash.
Flash in blinky with ESP-IDF.
Flash in blinky with Arduino.