These are very rough beginners’ notes for dealing with inexpensive microcontroller boards, and some of their peripherals. These were the result of a random shopping spree on AliExpress, and I haven’t used all of them in home projects yet, but it’s nice to know they’re readily available and very cheap to replace if necessary.
ESP8266 board with 0.96″ OLED display “HW-364A”
- Flash with esptool (micropython)
- Onboard display: 128×64, I2C (SCL: 12, SDA: 14), address 0x3C (The topmost 16 rows of pixels are yellow, the rest are blue)
ESP32-S2 “Mini”
- Flash with esptool (micropython)
- Onboard LED: GPIO 15
- Onboard button: GPIO 0 (hold down when powering-up for flash mode)
- Note: This arrived in a weird state that was unrecognizable by my PC, and when I put it in flash mode, it kept resetting every few seconds. To erase the flash, I had to connect it in flash mode and immediately run the esptool command to catch it before it reset again.
ESP32-C3 “Super Mini”
- Flash with esptool (micropython)
- Onboard LED: GPIO 8
Untitled ESP32-C3 board with 0.42″ OLED display
- Onboard display (the cutest thing ever): 72×40, I2C (SCL: 5, SDA: 6)
- Onboard LED: GPIO 8
- Note: The display on this board seems to work better with Arduino IDE (C code) rather than MicroPython. Use the
u8g2library to control the display.
ESP32-S3 “Super Mini”
- Flash with esptool (micropython)
- Onboard RGB LED (NeoPixel): GPIO 48
- Also a regular LED: GPIO 48
- Threw a heatsink on it, because why not.
Untitled RP2040 board #1
- Flash MicroPython directly from Thonny
- Onboard LED: GPIO 25
RP2040 board “YD-RP2040”, V1103/1084
- Flash MicroPython directly from Thonny
- Onboard RGB LED (NeoPixel): GPIO 23
- Note: to enable the NeoPixel, close the solder bridge labeled “RGB”, although on my board it was labeled “R58” (a worthy attempt at spelling “RGB” by a non-English speaker). If the solder bridge is left open, then GPIO 23 can be used as regular I/O.
- Onboard user button: GPIO 24
- Note: when initializing this pin for input, remember to enable the internal pull-up resistor:
usrButton = machine.Pin(24, machine.Pin.IN, machine.Pin.PULL_UP)
- Note: when initializing this pin for input, remember to enable the internal pull-up resistor:
- Another onboard LED: GPIO 25
RP2040 board “ProMicro”
- Flash MicroPython directly from Thonny
- Onboard LED: GPIO 17
RP2040 board “RP2040-Zero”, V1083
- Flash MicroPython directly from Thonny
- Onboard RGB LED (NeoPixel): GPIO 16
Doing stuff
Refer to MicroPython documentation!