ARM Pin mBed Pin LPCXpresso Pin Assignment Comment
P0.0 P9 9 i2c1 sda Internal I2C bus. Used for digipots and port expander.
P0.1 P10 10 i2c1 scl Internal I2C bus. Used for digipots and port expander.
P0.2 USBTX 21 uart0 txd Used for ISP programming of the bootloader and for debugging.
P0.3 USBRX 22 uart0 rxd Used for ISP programming of the bootloader and for debugging.
P0.4 P30 38 alpha_en_pin
P0.5 P29 39 alpha_dir_pin
P0.6 P8 8 spi1 ssel sdcard
P0.7 P7 7 spi1 sck sdcard
P0.8 P6 6 spi1 miso sdcard
P0.9 P5 5 spi1 mosi sdcard
P0.10 P28 40 beta_en_pin also i2c2 sda
P0.11 P27 41 beta_dir_pin also i2c2 scl
P0.15 P13 13 spi0 sck User spi port. used for rrd glcd
P0.16 P14 14 spi0 ssel User spi port. used for rrd glcd cs
P0.17 P12 12 spi0 miso User spi port.
P0.18 P11 11 spi0 mosi User spi port. used for rrd glcd
P0.19 - Pad17 gamma_en_pin also i2c3 sda on lpcxpresso e2prom
P0.20 - Pad18 gamma_dir_pin also i2c3 scl on lpcxpresso e2prom
P0.21 - 23 delta_en_pin
P0.22 - 24 delta_dir_pin lpcxpresso led
P0.23 P15 15 hotend.thermistor_pin
P0.24 P16 16 bed.thermistor_pin
P0.25 P17 17 thermistor2
P0.26 P18 18 thermistor3
P0.27 - 25 i2c0 sda User i2c port. sd cd on rrd glcd adapter
P0.28 - 26 i2c0 scl User i2c port. sd cs2 on rrd glcd adapter
P0.29 31 37 USB-D+
P0.30 32 36 USB-D-
P1.0 eth txd0
P1.1 eth txd1
P1.4 eth tx en
P1.8 eth crs
P1.9 eth rxd0
P1.10 eth rxd1
P1.14 eth rx err
P1.15 eth ref clk
P1.16 eth mdc
P1.17 eth mdio
P1.18 LED1 Pad1 led1 h/w PWM capable. can be free if leds_disable is set true in config.
P1.19 - Pad2 led2 can be free if leds_disable is set true in config.
P1.20 LED2 Pad3 led3 h/w PWM capable. can be free if leds_disable is set true in config.
P1.21 LED3 Pad4 led4 h/w PWM capable. can be free if leds_disable is set true in config.
P1.22 - Pad5 3rd small fet spare on 3 and 4 driver boards
P1.23 LED4 Pad6 3rd large fet spare on 3 and 4 driver boards, h/w PWM capable
P1.24 - Pad7 alpha_min_endstop h/w PWM capable
P1.25 - Pad8 alpha_max_endstop
P1.26 - Pad9 beta_min_endstop h/w PWM capable
P1.27 - Pad10 beta_max_endstop
P1.28 - Pad11 gamma_min_endstop
P1.29 - Pad12 gamma_max_endstop
P1.30 P19 19 spare used for click button on rrd glcd
P1.31 P20 20 spare used for buzzer on rrd glcd
P2.0 P26 42 alpha_step_pin h/w PWM capable
P2.1 P25 43 beta_step_pin h/w PWM capable
P2.2 P24 44 gamma_step_pin h/w PWM capable
P2.3 P23 45 delta_step_pin h/w PWM capable
P2.4 P22 46 psu.output_pin h/w PWM capable
P2.5 P21 47 bed.heater_pin h/w PWM capable
P2.6 - 48 fan.output_pin
P2.7 - 49 hotend.heater_pin
P2.8 - 50 epsilon_step_pin spare on 3 and 4 driver
P2.9 - Pad19 USB soft connect
P2.10 - 51 ISP button
P2.11 - 52 spare used for pause/kill/back pin on glcd
P2.12 - 53 kill button
P2.13 - 27 epsilon_dir_pin spare on 3 and 4 driver
P3.25 - Pad13 spare used for encoder pin for all panels, h/w PWM capable
P3.26 - Pad14 spare used for encoder pin for all panels, h/w PWM capable
P4.28 - Pad15 play/pause led
P4.29 - Pad16 epsilon_en_pin spare on 3 and 4 driver

NOTE The following pins are hardwired and would need to be changed in source code P0.2 P0.3 , P0.6-P0.9, P0.29, P0.30, P2.9, P2.10 The rest are configurable in config.

P0.* and P2.* can be setup as interrupt enabled pins.

smoothie_wiring_diagram.png