[FluidNC Issue#1482] Problem: Why is it a problem that a limit switch is hit at startup when there are separate + / – switches?

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Why is this a problem?

Grbl 3.9 [FluidNC v3.9.6 (wifi) ‘$’ for help]
[MSG:WARN: Active limit switch on Z axis motor 0]
[MSG:INFO: ALARM: Hard Limit]
ALARM:1
[MSG:ERR: Reset to continue]

The machine should know that it is at the positive limit and which way to move.

Controller Board

6 Pack External XYZ 10V

Machine Description

XYZ CNC, individual +/- limit switches on all axes

Input Circuits

limitnegpin: gpio.39:low
      limitpospin: gpio.32:low

Configuration file

board: 6 Pack
name: 6 Pack External XYZ 10V
meta: 2024-12-05 Leif
stepping:
  engine: I2S_STATIC
  idle_ms: 255
  pulse_us: 4
  dirdelayus: 1
  disabledelayus: 0
axes:
  x:
    stepspermm: 320
    maxratemmpermin: 3000
    accelerationmmper_sec2: 100
    maxtravelmm: 300
    soft_limits: true
    homing:
      cycle: 2
      positive_direction: false
      mpos_mm: 0
      feedmmper_min: 100
      seekmmper_min: 500
      settle_ms: 500
      seek_scaler: 1.1
      feed_scaler: 1.1
    motor0:
      limitnegpin: gpio.34:low
      limitpospin: gpio.33:low
      limitallpin: NO_PIN
      hard_limits: true
      pulloff_mm: 3
      standard_stepper:
        step_pin: i2so.2
        direction_pin: i2so.1
        disable_pin: i2so.0
  y:
    stepspermm: 320
    maxratemmpermin: 3000
    accelerationmmper_sec2: 100
    maxtravelmm: 600
    soft_limits: true
    homing:
      cycle: 2
      positive_direction: true
      mpos_mm: 0
      feedmmper_min: 100
      seekmmper_min: 500
      settle_ms: 500
      seek_scaler: 1.1
      feed_scaler: 1.1
    motor0:
      limitnegpin: gpio.35:low
      limitpospin: gpio.36:low
      limitallpin: NO_PIN
      hard_limits: true
      pulloff_mm: 3
      standard_stepper:
        step_pin: i2so.5
        direction_pin: i2so.4
        disable_pin: i2so.7
  z:
    stepspermm: 328.947
    maxratemmpermin: 1000
    accelerationmmper_sec2: 100
    maxtravelmm: 88
    soft_limits: true
    homing:
      cycle: 1
      positive_direction: true
      mpos_mm: 0
      feedmmper_min: 100
      seekmmper_min: 800
      settle_ms: 500
      seek_scaler: 1.1
      feed_scaler: 1.1
    motor0:
      limitnegpin: gpio.39:low
      limitpospin: gpio.32:low
      limitallpin: NO_PIN
      hard_limits: true
      pulloff_mm: 3
      standard_stepper:
        step_pin: i2so.10
        direction_pin: i2so.9
        disable_pin: i2so.8
  a:
    stepspermm: 80
    maxratemmpermin: 1000
    accelerationmmper_sec2: 25
    maxtravelmm: 1000
    motor0:
      limitallpin: NO_PIN
      limitnegpin: NO_PIN
      limitpospin: NO_PIN
      hard_limits: false
      pulloff_mm: 1
      standard_stepper:
        step_pin: i2so.13
        direction_pin: i2so.12
        disable_pin: i2so.15:low
i2so:
  bck_pin: gpio.22
  data_pin: gpio.21
  ws_pin: gpio.17
spi:
  miso_pin: gpio.19
  mosi_pin: gpio.23
  sck_pin: gpio.18
sdcard:
  carddetectpin: NO_PIN
  cs_pin: gpio.5
start:
  must_home: false
  deactivate_parking: false
  check_limits: true
10V:
  forward_pin: gpio.16
  reverse_pin: gpio.4
  pwm_hz: 5000
  output_pin: gpio.26
  enable_pin: i2so.21
  directionpin: NOPIN
  disablewiths0: false
  s0withdisable: true
  spinup_ms: 5000
  spindown_ms: 5000
  tool_num: 0
  speed_map: 0=0.000% 1000=0.000% 24000=100.000%
  offonalarm: false
i2c0:
  sda_pin: gpio.14
  scl_pin: gpio.13

Startup Messages

rbl 3.9 [FluidNC v3.9.6 (wifi) '$' for help]
$Startup/Show
[MSG:INFO: FluidNC v3.9.6 https://github.com/bdring/FluidNC]
[MSG:INFO: Compiled with ESP32 SDK:v4.4.7-dirty]
[MSG:INFO: Local filesystem type is littlefs]
[MSG:INFO: Configuration file:config.yaml]
[MSG:INFO: Machine 6 Pack External XYZ 10V]
[MSG:INFO: Board 6 Pack]
[MSG:INFO: I2SO BCK:gpio.22 WS:gpio.17 DATA:gpio.21Min Pulse:2us]
[MSG:INFO: SPI SCK:gpio.18 MOSI:gpio.23 MISO:gpio.19]
[MSG:INFO: SD Card cspin:gpio.5 detect:NOPIN freq:8000000]
[MSG:INFO: I2C SDA: gpio.14, SCL: gpio.13, Freq: 100000, Bus #: 0]
[MSG:INFO: Stepping:I2S_STATIC Pulse:4us Dsbl Delay:0us Dir Delay:1us Idle Delay:255ms]
[MSG:INFO: Axis count 4]
[MSG:INFO: Axis X (0.000,300.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.2 Dir:I2SO.1 Disable:I2SO.0]
[MSG:INFO:  Neg Limit gpio.34:low]
[MSG:INFO:  Pos Limit gpio.33:low]
[MSG:INFO: Axis Y (-600.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.5 Dir:I2SO.4 Disable:I2SO.7]
[MSG:INFO:  Neg Limit gpio.35:low]
[MSG:INFO:  Pos Limit gpio.36:low]
[MSG:INFO: Axis Z (-88.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.10 Dir:I2SO.9 Disable:I2SO.8]
[MSG:INFO:  Neg Limit gpio.39:low]
[MSG:INFO:  Pos Limit gpio.32:low]
[MSG:INFO: Axis A (-1000.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.13 Dir:I2SO.12 Disable:I2SO.15:low]
[MSG:INFO: Kinematic system: Cartesian]
[MSG:INFO: Connecting to STA SSID:FMK_A1]
[MSG:INFO: Connecting.]
[MSG:INFO: Connecting..]
[MSG:INFO: No SSID]
[MSG:INFO: AP SSID FluidNC IP 192.168.10.1 mask 255.255.255.0 channel 1]
[MSG:INFO: AP started]
[MSG:INFO: WiFi on]
[MSG:INFO: Captive Portal Started]
[MSG:INFO: HTTP started on port 80]
[MSG:INFO: Telnet started on port 23]
[MSG:INFO: 10V Spindle Ena:I2SO.21 Out:gpio.26 Dir:NO_PIN Fwd:gpio.16 Rev:gpio.4 Freq:5000Hz Period:8191]
ok

User Interface Software

No response

What happened?

I’m trying to calibrate the travel length of xyz, and when it hits a limit switch, it is not possible to move away from the activated switch.

It should only disable moving towards the activated switch.

GCode File

No response

Other Information

No response