GPIO Allocation
The table below lists all ESP32 GPIOs used by the SLWF-09, their assigned functions, and the type of interface or peripheral they control.
Pins marked with “*” are only used when the corresponding add-on module (Ethernet or Microphone) is installed.
The PoE add-on does not consume any GPIO pins.
Type | Function | GPIO |
---|---|---|
Boot/Prog | BOOT mode | GPIO0 |
LED | LED1 control | GPIO2 |
LED | LED data output (DATA) | GPIO4 |
LED | LED clock (for clocked LEDs) | GPIO17 |
I²C | I²C SCL (expansion) | GPIO5 |
I²C / Mic | I²C SDA / Mic SCK* | GPIO14 |
Mic | Mic WS* | GPIO15 |
Mic | Mic SD* | GPIO32 |
Ethernet | PHY RXER* | GPIO13 |
Ethernet | PHY Clock Enable / OSCEN* | GPIO16 |
Ethernet | MDIO* | GPIO18 |
Ethernet | TXD0* | GPIO19 |
Ethernet | TXEN* | GPIO21 |
Ethernet | TXD1* | GPIO22 |
Ethernet | MDC* | GPIO23 |
Ethernet | RXD0* | GPIO25 |
Ethernet | RXD1* | GPIO26 |
Ethernet | CRS_DV* | GPIO27 |
Relay | GPIO33 | |
Button | External button B2 | GPIO34 |
DIY1 | Voltage |
GPIO36 |
Ethernet | Ethernet detect* | GPIO37 |
DIY2 | Output / MOSFET control | GPIO38 |
Button | External button B1 | GPIO39 |
Reserved | Not connected (NC) | GPIO35 |