---
tag: m0043
title: Debug Pins
brief: Get information about pins.
author: thinkyhead

experimental: true
requires: PINS_DEBUGGING
group: debug

codes: [ M43 ]

notes:
  - Requires `PINS_DEBUGGING`. This feature should be disabled for production use.

parameters:
  -
    tag: P
    optional: true
    description: Digital Pin Number
    values:
      -
        tag: pin
        type: int
  -
    tag: W
    optional: true
    description: Watch pins
  -
    tag: E
    optional: true
    description: Watch endstops
    values:
      -
        type: bool
  -
    tag: T
    optional: true
    description: Toggle pins - see [`M43 T`](/docs/gcode/M043-T.html) for options
    values:
  -
    tag: S
    optional: true
    description: Test BLTouch type servo probes. Use `P` to specify servo index (0-3). Defaults to 0 if `P` omitted
    values:
  -
    tag: I
    optional: true
    description: Ignore protection when reporting values
    values:


examples:
  -
    pre: Get a report on all pins
    code: M43
  -
    pre: Get a report on all pins, ignore pin protection list when displaying values
    code: M43 I
  -
    pre: Watch pin 56 for changes
    code: M43 P56 W
  -
    pre: Start watching endstops
    code: M43 E1
  -
    pre: Toggle pins 3-6 five times with 1 second low and 1 second high pulses but only if the pin isn't in the protected list.
    code: M43 T S3 L6 R5 W1000
  -
    pre: Test probe controlled by servo index 2.
    code: M43 S P2
---

When setting up or debugging a machine it's useful to know how pins are assigned to functions by the firmware, and to be able to find pins for use with new functions. [`M43`](/docs/gcode/M043.html) provides these tools. [`M43`](/docs/gcode/M043.html) by itself reports all pin assignments. Use `P` to specify a single pin. Use `I` to report the values on pins that are protected. Use `W` to watch the specified pin, or all pins. Use the `E` option to monitor endstops. Use `S` option to test a BLTouch type servo probe. Use `T` option to toggle pins.

The `W` watch mode option continues looping, blocking all further commands, until the board is reset. If `EMERGENCY_PARSER` is enabled, [`M108`](/docs/gcode/M108.html) may also be used to exit the watch loop without needing to reset the board.

See [`M43 T`](/docs/gcode/M043-T.html) for Pins Debugging toggle options.