Pinout
- This page lists the pinout of the FLY-ERCF tool board after flashing Klipper firmware. Pin numbers are subject to the product schematic.
UART/CSis the driver communication pin: it functions as UART when using TMC2209, and as chip selectCSwhen using SPI drivers, with the same pin being multiplexed.ENis the enable pin, which is typically active low in Klipper configuration (with theenable_pinprefixed by!).
Interactive Pin Hotspots
The image below uses the product image of FLY-ERCF and the same hotspot data. Use the device-type filters to show only compatible connectors; click a hotspot to see which devices it accepts, common Klipper configuration options, and notes. Hover to see the connector name and pins; always verify the silkscreen and connector positions against the physical board and schematic.

Hover to see the pin; click a hotspot to view compatible devices and configs. Pins can be copied from the detail panel, except for driver connectors.
Driver Pins
| Driver | STEP | DIR | EN | UART/CS | Endstop |
|---|---|---|---|---|---|
| DRIVER0 | gpio2 | gpio1 | gpio3 | gpio0 | - |
| DRIVER1 | gpio7 | gpio8 | gpio6 | gpio9 | - |
Before starting, completely shut down the printer and disconnect the power supply. Do not plug or unplug wiring harnesses, organize interface wiring, or touch terminals while the power is on.
Endstops
| Function | Pin |
|---|---|
| Endstop Port 0 | gpio20 |
| Endstop Port 1 | gpio15 |
For wiring of micro switches, optical endstops, proximity sensors, and TAP, see: Endstop Wiring Guide
Servo
| Function | Pin |
|---|---|
| Servo 0 | gpio21 |
Extended Output
| Function | Pin |
|---|---|
| EXTRA / General Purpose Output | gpio14 |
PWM
| PWM Function | Pin |
|---|---|
| Servo 0 | gpio21 |
| EXTRA / General Purpose Output | gpio14 |