- Stock: 2
- Model: SKR 1.4
Model:
SKR V 1.4 LPC1768 100 MHz
SKR V 1.4 TURBO LPC1769 120 MHz
SKR 2 STM32 180 MHz
SKR 3 STM32 480 MHz
The BIGTREETECH SKR V1.4 is a 32-bit control board for 3D printers and DIY machines built around the NXP LPC1768 microcontroller. It combines five replaceable driver sockets, six motor connectors, bed, heater and fan outputs, a microSD reader and multiple expansion interfaces.
It is particularly useful for upgrading an 8-bit controller or building a custom machine with Marlin or Klipper. It is not a universal drop-in replacement: power, pinout, drivers, sensors, display, mounting space, wiring and firmware configuration must all be checked before installation.
SKR V1.4 or SKR V1.4 Turbo
Both versions share the same PCB, connectors, pinout and dimensions. Their main difference is the microcontroller: this SKR V1.4 uses an LPC1768 running at up to 100 MHz, while the BIGTREETECH SKR V1.4 Turbo uses an LPC1769 running at up to 120 MHz. Always select the matching board definition and microcontroller when compiling firmware.
| Feature | SKR V1.4 | SKR V1.4 Turbo |
|---|---|---|
| Microcontroller | NXP LPC1768FBD100 | NXP LPC1769FBD100 |
| Architecture | 32-bit Arm Cortex-M3 | 32-bit Arm Cortex-M3 |
| Maximum frequency | 100 MHz | 120 MHz |
| Marlin board definition | BOARD_BTT_SKR_V1_4 | BOARD_BTT_SKR_V1_4_TURBO |
| PCB, pinout and mounting | Shared by both versions | |
Technical specifications
| Feature | Value or condition |
|---|---|
| Microcontroller | NXP LPC1768FBD100, Arm Cortex-M3, up to 100 MHz |
| MCU memory | Up to 512 kB Flash and 64 kB SRAM |
| Main power input | 12 or 24 V DC |
| Logic level | 3.3 V |
| Drivers | 5 replaceable sockets: X, Y, Z, E0 and E1 |
| Motor connectors | 6: X, Y, two Z connectors, E0 and E1 |
| Temperature sensors | 3 inputs: TH0, TH1 and TB |
| Controlled outputs | Bed, HE0, HE1/FAN1 and FAN0 |
| Direct fan outputs | FAN2 and FAN3 receive supply voltage and are not controlled PWM outputs |
| Storage | On-board microSD reader |
| PCB dimensions | 109.67 × 84.30 mm |
| Mounting centres | 101.85 × 76.30 mm |
Connectivity and expansion
- USB Type-B and microSD reader for communication and firmware updates.
- TFT, EXP1 and EXP2 ports for compatible displays, subject to wiring and firmware.
- Connections for endstops, probe, servo, Neopixel, I2C, SPI and SWD.
- ESP-01S socket: the connector does not provide built-in Wi-Fi; a compatible module and configuration are required.
- Header for the optional BIGTREETECH 12/24 V to 5 V DCDC module.
STEP/DIR, UART and SPI drivers
The five sockets support different operating modes depending on the driver model, installed jumpers and firmware configuration. A StepStick-like footprint alone does not guarantee compatibility: orientation, pinout, logic voltage, motor voltage, current and communication signals must all be verified.
- STEP/DIR: basic mode for compatible drivers; microsteps and current may depend on jumpers and potentiometer.
- UART: provides firmware configuration for compatible drivers such as the BIGTREETECH TMC2209.
- SPI: available for compatible drivers when the jumpers and CS pins are correctly configured.
- DIAG and sensorless homing: only when supported by the driver, wiring, firmware and mechanics; individual calibration is required.
Two Z connectors do not provide two independent axes
The two Z motor connectors are wired to the same Z driver socket. They can power two motors from one driver, but they do not provide independent side adjustment or automatic dual-Z levelling. Independent Z motors require another available driver plus matching wiring and firmware changes.
Heaters, bed and fans
The board provides MOSFET outputs for the bed, two heater functions and fans. HE1/FAN1 is a shared role that must be assigned for the actual machine. FAN2 and FAN3 are direct supply-voltage connectors and run whenever the board is powered.
Machine compatibility
The board can be used in Cartesian, CoreXY, Delta/Kossel and other stepper-driven DIY machines when its axes, extruders, sensors, outputs and expansion resources are sufficient. Creality Ender-3, CR-10 or Anet family conversions commonly need a case or bracket, connector and wiring changes, machine-specific compiled firmware and checks for the display, probes and fans.
For a 3DSteel V2, we offer a printed enclosure specifically designed for the SKR V1.4. Similar size or architecture does not guarantee direct mounting in other machines.
Marlin configuration
In a current Marlin version, select this board definition:
#define MOTHERBOARD BOARD_BTT_SKR_V1_4Compile for LPC1768, then configure kinematics, driver types, thermistors, display, probe, endstops, steps, limits and safety protections for the actual machine. Do not reuse another printer's configuration without reviewing every relevant setting.
Klipper configuration
Klipper provides an official generic configuration for the SKR V1.4 family. Select the LPC176x architecture and the LPC1768 processor when building the MCU firmware. The generic file provides pin assignments, but its currents, PID values, sensors, dimensions, kinematics and serial path are examples that must be replaced.
Read the actual device identifier from /dev/serial/by-id/; do not copy one from another installation. TMC drivers in UART or SPI need one correctly configured section per axis.
Initial firmware update
- Build the firmware for the exact LPC1768 version.
- Copy the resulting file as
firmware.binto a compatible, correctly formatted microSD card. - With the board powered off, insert the card and power it again.
- Confirm that the file has been renamed to
firmware.curbefore continuing. - Test communication and inputs with heaters disconnected, then check each output under controlled conditions.
The microSD card required for flashing should not be assumed to be included unless the current package explicitly states it.
It is for you if
- You want a well-documented 32-bit controller for Marlin or Klipper.
- You need five replaceable drivers and value STEP/DIR, UART or SPI options.
- You are building a DIY machine or conversion and can adapt mounting, wiring and firmware.
- You need two physical Z motor connectors driven by one controller.
It is not for you if
- You need a modern board with integrated drivers, Linux host or built-in CAN.
- You require two independently controlled Z motors without assigning another driver socket.
- You expect a drop-in replacement with no firmware compilation or connector checks.
- Your system uses unverified 5 V signals with the board's 3.3 V logic.
Before connecting
- Always disconnect power and confirm input polarity.
- Never insert or remove drivers or motors while the board is powered.
- Check each driver's orientation and fit the jumpers before applying power.
- Configure the correct temperature sensor and verify a plausible room-temperature reading before enabling a heater.
- Make sure every fan matches the voltage present at its connector.
- Provide airflow for the drivers and electronics, especially in enclosed cases.
Package and required parts
The BIGTREETECH SKR V1.4 board is supplied. Drivers, microSD card, display, Wi-Fi module, DCDC module, sensors, cables and other peripherals are only included when explicitly listed for the selected package.
