#1 – bdring 于 2025-08-31

You have a switch that is active at startup. All switches except for the door switch should be momentary that activate when pushed.

You can see what is active with the ? command.

Change the :low to :high in the switch config values.

http://wiki.fluidnc.com/en/config/control#initial-state

#2 – Cyberhornet34 于 2025-08-31

Thanks for fast reply,
I would love that would be so simple !
here my ? command:
if i define :high, all switches are trigered ! :low is a good configuration

#3 – Cyberhornet34 于 2025-08-31

Sometimes i don’t get Alarm at startup, i get IDLE but when i touch reset switch, even few minutes after startup, i get:
[MSG:ERR: reset_pin is active at startup]
[MSG:INFO: ALARM: Control Pin Initially On]
ALARM:11

#4 – MitchBradley 于 2025-08-31

Are you using external pullups on the control pins, or depending on the internal pullups? If you are using the internal pullups, the RC time constant could be quite long. What is the filter capacitor value?

#5 – Cyberhornet34 于 2025-08-31

Hi Mitch,
Yes i’m using internal pullups on control pins
I’m using a R/C filter (low pass) with a 100R resistors and 100nf capacitors.

here’s my old config that worked well in GRBL ESP32

// Inverts pin logic of the control command pins based on a mask. This essentially means you can use
// normally-closed switches on the specified pins, rather than the default normally-open switches.
// The mask order is ...
// Macro3 | Macro2 | Macro 1| Macr0 |Cycle Start | Feed Hold | Reset | Safety Door
// For example B1101 will invert the function of the Reset pin.
#define INVERTCONTROLPIN_MASK B00001111
#define ENABLECONTROLSW_DEBOUNCE     // Default disabled. Uncomment to enable.
#define CONTROLSWDEBOUNCE_PERIOD 32  // in milliseconds default 32 microseconds

#6 – MitchBradley 于 2025-08-31

FluidNC has a fixed debounce period of 5 ms. The internal pullup can be as high as 100K, which results in a 10 ms time constant. Using an internal pullup for any signal that is potentially connected to an external device is problematic. Add 10K pullups to your circuit.

#7 – Cyberhornet34 于 2025-08-31

I just tested to add 10K pullups instead of internal one, i get the same issue…
By the way, when i put reset pin on the opto circuit (who as external 10k pullup), i never get Alarm at startup, but i still get Alarm11 when i trigger reset switch after startup.
I’m going to go crazy !

!Image

#8 – bdring 于 2025-08-31

Show the console text on the reset.

I cannot test until late tomorrow.

#9 – MitchBradley 于 2025-08-31

We probably need to special-case the check for reset active on restart.

#10 – Cyberhornet34 于 2025-08-31

when i trigger reset switch, i get this:

Grbl 3.9 [FluidNC v3.9.8 (wifi) '$' for help]
[MSG:ERR: reset_pin is active at startup]
[MSG:INFO: ALARM: Control Pin Initially On]
ALARM:11
Grbl 3.9 [FluidNC v3.9.8 (wifi) '$' for help]
Grbl 3.9 [FluidNC v3.9.8 (wifi) '$' for help]

#11 – MitchBradley 于 2025-08-31

I think I know what is happening. It will take me awhile to fix it because I am working on something else right now.

#12 – Cyberhornet34 于 2025-09-01

Thank you for everything you do, Bart and you.

#13 – bdring 于 2025-09-01

I did a little testing and the control pins appear to be working as designed.

Try sending the $message/level=debug command. It will show you all switch state changes. This will show you if the state is changing due to noise, etc.

#14 – Cyberhornet34 于 2025-09-01

Hi Bart,
The startup issue i got cames from noise on R/C entries and FLuidNC who have not the same level of debounce than GRBL ESP32. (i’ll redo a new board with all opto entries)
I put probe/reset/start/hold on opto entries of my board (instead of endstops) and i don’t get any issue at startup, BUT, when i’m triggering the reset switch, i still get the Alarm

Grbl 3.9 [FluidNC v3.9.8 (wifi) '$' for help]
ok
[MSG:DBG: reset_pin 1]
Grbl 3.9 [FluidNC v3.9.8 (wifi) '$' for help]
[MSG:ERR: reset_pin is active at startup]
[MSG:DBG: reset_pin 0]
[MSG:INFO: ALARM: Control Pin Initially On]
ALARM:11

A friend with a different board get the same issue when triggering reset_pin, its board has entries with opto+shmidt triggers, external pullups…. well protected !
We only get issue with Reset_pin. No problem with probe,start, hold…

#15 – MitchBradley 于 2025-09-01

As I said, I think I know the cause of the problem. I just need to find time to fix it. I am doing many other things at the moment.

#16 – Cyberhornet34 于 2025-09-01

Thank you Mitch

#17 – HTheatre 于 2025-09-01

Hi Bart and Mitch,

I’m the Cyberhornet34’s friend. Don’t worry Mitch. we red you and understood you are working on many other things at the same time. We’ll be patient. So, my post is only for information which could help you and confirm your analisys.

Here is my controller board’s schematic.

Here is my config.yaml file.

board: SixDeCNC
name: XYZABC external drivers
meta: (09/01/2025) By HTheatre
arctolerancemm: 0.002
junctiondeviationmm: 0.010
verbose_errors: false
report_inches: false
enableparkingoverride_control: false
uselinenumbers: false
start:
  must_home: false
  deactivate_parking: false
  check_limits: true
stepping:
  engine: I2S_STREAM
  idle_ms: 250
  pulse_us: 4
  dirdelayus: 0
  disabledelayus: 0
  segments: 12
axes:
  sharedstepperdisablepin: NOPIN
  x:
    stepspermm: 60.000
    maxratemmpermin: 2500.000
    accelerationmmper_sec2: 80.000
    maxtravelmm: 550.000
    soft_limits: false
    homing:
      cycle: 2
      allowsingleaxis: true
      positive_direction: false
      mpos_mm: 0
      seekmmper_min: 2000.000
      feedmmper_min: 200.000
      settle_ms: 250
      seek_scaler: 1.100
      feed_scaler: 1.100
    motor0:
      limitnegpin: NO_PIN
      limitpospin: NO_PIN
      limitallpin: gpio.33:low
      hard_limits: false
      pulloff_mm: 2.000
      standard_stepper:
        disable_pin: I2SO.1
        direction_pin: I2SO.3
        step_pin: I2SO.5
  y:
    stepspermm: 60.000
    maxratemmpermin: 2500.000
    accelerationmmper_sec2: 80.000
    maxtravelmm: 570.000
    soft_limits: false
    homing:
      cycle: 2
      allowsingleaxis: true
      positive_direction: false
      mpos_mm: 0
      seekmmper_min: 2000.000
      feedmmper_min: 200.000
      settle_ms: 250
      seek_scaler: 1.100
      feed_scaler: 1.100
    motor0:
      limitnegpin: NO_PIN
      limitpospin: NO_PIN
      limitallpin: gpio.32:low
      hard_limits: false
      pulloff_mm: 2.000
      standard_stepper:
        disable_pin: I2SO.7
        direction_pin: I2SO.9
        step_pin: I2SO.11
  z:
    stepspermm: 400.000
    maxratemmpermin: 1000.000
    accelerationmmper_sec2: 50.000
    maxtravelmm: 100.000
    soft_limits: false
    homing:
      cycle: 1
      allowsingleaxis: true
      positive_direction: true
      mpos_mm: 0
      seekmmper_min: 2000.000
      feedmmper_min: 200.000
      settle_ms: 250
      seek_scaler: 1.100
      feed_scaler: 1.100
    motor0:
      limitnegpin: NO_PIN
      limitpospin: NO_PIN
      limitallpin: gpio.35:low
      hard_limits: false
      pulloff_mm: 2.000
      standard_stepper:
        disable_pin: I2SO.13
        direction_pin: I2SO.14
        step_pin: I2SO.15
  a:
    stepspermm: 100.000
    maxratemmpermin: 1000.000
    accelerationmmper_sec2: 80.000
    maxtravelmm: 300.000
    soft_limits: false
    homing:
      cycle: 0
      allowsingleaxis: false
      positive_direction: false
      mpos_mm: 0
      seekmmper_min: 2000.000
      feedmmper_min: 200.000
      settle_ms: 250
      seek_scaler: 1.100
      feed_scaler: 1.100
    motor0:
      limitnegpin: NO_PIN
      limitpospin: NO_PIN
      limitallpin: gpio.34:low
      hard_limits: false
      pulloff_mm: 2.000
      standard_stepper:
        disable_pin: I2SO.0
        direction_pin: I2SO.2
        step_pin: I2SO.4
  b:
    stepspermm: 100.000
    maxratemmpermin: 1000.000
    accelerationmmper_sec2: 80.000
    maxtravelmm: 300.000
    soft_limits: false
    homing:
      cycle: 0
      allowsingleaxis: false
      positive_direction: false
      mpos_mm: 0
      seekmmper_min: 2000.000
      feedmmper_min: 200.000
      settle_ms: 250
      seek_scaler: 1.100
      feed_scaler: 1.100
    motor0:
      limitnegpin: NO_PIN
      limitpospin: NO_PIN
      limitallpin: gpio.39:low
      hard_limits: false
      pulloff_mm: 2.000
      standard_stepper:
        disable_pin: I2SO.6
        direction_pin: I2SO.8
        step_pin: I2SO.10
  c:
    stepspermm: 100.000
    maxratemmpermin: 1000.000
    accelerationmmper_sec2: 80.000
    maxtravelmm: 300.000
    soft_limits: false
    homing:
      cycle: 0
      allowsingleaxis: false
      positive_direction: false
      mpos_mm: 0
      seekmmper_min: 2000.000
      feedmmper_min: 200.000
      settle_ms: 250
      seek_scaler: 1.100
      feed_scaler: 1.100
    motor0:
      limitnegpin: NO_PIN
      limitpospin: NO_PIN
      limitallpin: gpio.36:low
      hard_limits: false
      pulloff_mm: 2.000
      standard_stepper:
        disable_pin: I2SO.12
        direction_pin: I2SO.16
        step_pin: I2SO.17
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:
  cs_pin: gpio.5
  carddetectpin: NO_PIN
control:
  safetydoorpin: NO_PIN
  reset_pin: gpio.16:low
  feedholdpin: gpio.4:low
  cyclestartpin: gpio.26:low
  macro0pin: NOPIN
  macro1pin: NOPIN
  macro2pin: NOPIN
  macro3pin: NOPIN
coolant:
  flood_pin: I2SO.19
  mist_pin: I2SO.18
  delay_ms: 0
probe:
  pin: gpio.27
  checkmodestart: true
macros:
  startup_line0:
  startup_line1:
  macro0:
  macro1:
  macro2:
  macro3:
  
SERVO RC
user_outputs:
  analog0_pin: gpio.25
  analog1_pin: gpio.12
  #analog2_pin: gpio.13
  analog2pin: NOPIN
  #analog3_pin: gpio.15
  analog3pin: NOPIN
  analog0_hz: 50
  analog1_hz: 50
  analog2_hz: 50
  analog3_hz: 50
  digital0_pin: I2SO.23
  digital1_pin: I2SO.22
  digital2pin: NOPIN
  digital3pin: NOPIN
SPINDLE
10V:
  forward_pin: I2SO.20
  reverse_pin: I2SO.21
  pwm_hz: 2000
  output_pin: gpio.2
  enable_pin: I2SO.24
  directionpin: NOPIN
  disablewiths0: false
  s0withdisable: true
  spinup_ms: 0
  spindown_ms: 0
  tool_num: 0
  speed_map: 0=0.000% 4999=0.000% 5000=5.000% 5001=10.000% 25000=100.000%
LASER
Laser:
  pwm_hz: 2000
  output_pin: gpio.14:low
  enablepin: NOPIN
  disablewiths0: false
  s0withdisable: true
  tool_num: 100
  speed_map: 0=0.000% 1000=100.000%
  offonalarm: true

Here is the start sequence of FluidNC: no error or warning messages. I only have something wrong on the Z endstop entry. I will fix it. This is probably due to a defective endstop switch.

[MSG:INFO: FluidNC v3.9.8 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 XYZABC external drivers]
[MSG:INFO: Board SixDeCNC]
[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: Stepping:I2S_STREAM Pulse:4us Dsbl Delay:0us Dir Delay:0us Idle Delay:250ms]
[MSG:INFO: User Digital Output: 0 on Pin:I2SO.23]
[MSG:INFO: User Digital Output: 1 on Pin:I2SO.22]
[MSG:INFO: User Analog Output: 0 on Pin:gpio.25 Freq:50Hz]
[MSG:INFO: User Analog Output: 1 on Pin:gpio.12 Freq:50Hz]
[MSG:INFO: Axis count 6]
[MSG:INFO: Axis X (0.000,550.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.5 Dir:I2SO.3 Disable:I2SO.1]
[MSG:INFO:  All Limit gpio.33:low]
[MSG:INFO: Axis Y (0.000,570.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.11 Dir:I2SO.9 Disable:I2SO.7]
[MSG:INFO:  All Limit gpio.32:low]
[MSG:INFO: Axis Z (-100.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.15 Dir:I2SO.14 Disable:I2SO.13]
[MSG:INFO:  All Limit gpio.35:low]
[MSG:INFO: Axis A (0.000,300.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.4 Dir:I2SO.2 Disable:I2SO.0]
[MSG:INFO:  All Limit gpio.34:low]
[MSG:INFO: Axis B (0.000,300.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.10 Dir:I2SO.8 Disable:I2SO.6]
[MSG:INFO:  All Limit gpio.39:low]
[MSG:INFO: Axis C (0.000,300.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     standard_stepper Step:I2SO.17 Dir:I2SO.16 Disable:I2SO.12]
[MSG:INFO:  All Limit gpio.36:low]
[MSG:INFO: reset_pin gpio.16:low]
[MSG:INFO: feedholdpin gpio.4:low]
[MSG:INFO: cyclestartpin gpio.26:low]
[MSG:INFO: Kinematic system: Cartesian]
[MSG:INFO: STA SSID is not set]
[MSG:INFO: AP SSID FluidNC IP 192.168.0.1 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.24 Out:gpio.2 Dir:NO_PIN Fwd:I2SO.20 Rev:I2SO.21 Freq:2000Hz Period:32767]
[MSG:INFO: Laser Ena:NO_PIN Out:gpio.14:low Freq:2000Hz Period:32767]
[MSG:INFO: Flood coolant I2SO.19]
[MSG:INFO: Mist coolant I2SO.18]
[MSG:INFO: Probe gpio.27]
ok

And finally, here is the alarm message I get when I press the RESET button. I use momentary and normally closed switches on all the X, Y, Z, A, B, C (endstops), START and HOLD entries.

SixDeCNCschematic.pdf
SixDeCNCschematic.pdf
Grbl 3.9 [FluidNC v3.9.8 (wifi) '$' for help]
$Report/Interval=300
[MSG:WARN:: Active limit switch on Z axis motor 0]
[MSG:ERR: reset_pin is active at startup]
[MSG:INFO: ALARM: Control Pin Initially On]
ALARM:11
ALARM:11
[MSG:INFO: websocket auto report interval set to 300 ms]
ok

[GC:G0 G54 G17 G21 G90 G94 M5 M9 T0 F0 S0]