Notes on driving onboard RGB LEDs on various ESP32 S2 dev boards with micropython or circuitpython

esp32_s2_rgb_led_micropython.md

Setup

Starting with development boards:

• esp32 s2 Saola-1. Has a WS2812 on pin GPIO18 Saola schematic
• Feather s2 has an APA102 connected on two pins ( IO45 clock and MTDO data). Feather s2 schematic
• ESP32-S2-DevKitM-1 Has a WS2812 connected on GPIO18 . Schematic

Micropython RGB LED driver references:

• APA102 micropython ref
• WS2812 neopixel micropython or maybe more applicable on esp32 alternate neopixel tutorial

Examples that work:

WS2812 on Saola (with micropython)

import machine, time, neopixel, random
rgb_pin = machine.Pin(18)
np = neopixel.NeoPixel(rgb_pin, 1)

while True:
    red = random.randint(0, 129)
    green = random.randint(0, 129)
    blue = random.randint(0, 129)
    np[0] = (red, green, blue)
    np.write()
    time.sleep_ms(50)

APA102 on FeatherS2 (with CircuitPython)

You'll first need to download the dotstar library adafruit_dotstar.py file into /lib (assuming CircuitPython is already installed on the FeatherS2).

import board, time, random
# import apa102
import adafruit_dotstar
# IO45 clock and MTDO data
clock_pin = board.APA102_SCK
data_pin = board.APA102_MOSI
loop_count = 0

led_strip = adafruit_dotstar.DotStar(clock_pin, data_pin, 1)

while True:
    red = random.randint(0, 129)
    green = random.randint(0, 129)
    blue = random.randint(0, 129)
    brightness = 16
    led_strip[0] = (red, green, blue, brightness)
    print(loop_count)
    loop_count = loop_count + 1
    time.sleep(1)