Problem: G93 timing inaccurate #1372

AndreasEpp · 2024-11-06T09:13:33Z

Wiki Search Terms

G93, feedrate, inverse

Controller Board

ESP32 WROOM-32

Machine Description

Two naked boards without any periphery connected except two probes to my oscilloscope to measure the timing.
One machine is configured with 4 axis and the other one is configured with 1 axis (plus two dummy ones).
Both machines have user output pins defined. I toggle these pins at the start and end of the program to measure timing with my oscilloscope.

I have pasted both my config files in the config file section

Input Circuits

Two naked boards without any periphery connected except two probes to my oscilloscope to measure the timing.

Configuration file

#########################################
# first config file
board: ESPDUINO-32
name: PANTS


user_outputs:
  digital0_pin: gpio.2
  digital1_pin: gpio.4

axes:
  shared_stepper_disable_pin: gpio.12:high
  x:
    steps_per_mm: 160
    max_rate_mm_per_min: 10000
    acceleration_mm_per_sec2: 500
    max_travel_mm: 1000
    motor0:
      stepstick:
        direction_pin: gpio.16:low
        step_pin: gpio.26

  y:
    steps_per_mm: 257.777
    max_rate_mm_per_min: 10000
    acceleration_mm_per_sec2: 500
    max_travel_mm: 1000
    motor0:
      stepstick:
        direction_pin: gpio.27
        step_pin: gpio.25

  z:
    steps_per_mm: 257.777
    max_rate_mm_per_min: 10000
    acceleration_mm_per_sec2: 500
    max_travel_mm: 1000
    motor0:
      stepstick:
        direction_pin: gpio.14:low
        step_pin: gpio.17

  a:
    steps_per_mm: 44.444
    max_rate_mm_per_min: 40000
    acceleration_mm_per_sec2: 3000
    motor0:
      stepstick:
        direction_pin: gpio.18
        step_pin: gpio.19

##############################
# second config file
board: Wemos D1 mini
name: Rotodactyl

user_outputs:
  digital0_pin: gpio.2
  digital1_pin: gpio.4


axes:
  shared_stepper_disable_pin: gpio.27:high

  x:
    steps_per_mm: 113.333
    max_rate_mm_per_min: 16900
    acceleration_mm_per_sec2: 500

    motor0:
      limit_all_pin: NO_PIN
      stepstick:
        direction_pin: gpio.32
        step_pin: gpio.25

Startup Messages

#########################
# First startup message #
#########################
ets Jul 29 2019 12:21:46

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff0030,len:1184
load:0x40078000,len:13260
load:0x40080400,len:3028
entry 0x400805e4
[MSG:INFO: uart_channel0 created]
[MSG:RST]
[MSG:INFO: FluidNC v3.9.1 https://github.com/bdring/FluidNC]
[MSG:INFO: Compiled with ESP32 SDK:v4.4.7-dirty]
[MSG:INFO: Local filesystem type is spiffs]
[MSG:INFO: Configuration file:config.yaml]
[MSG:INFO: Machine PANTS]
[MSG:INFO: Board ESPDUINO-32]
[MSG:INFO: Stepping:RMT Pulse:4us Dsbl Delay:0us Dir Delay:0us Idle Delay:255ms]
[MSG:INFO: User Digital Output: 0 on Pin:gpio.2]
[MSG:INFO: User Digital Output: 1 on Pin:gpio.4]
[MSG:INFO: Axis count 4]
[MSG:INFO: Shared stepper disable gpio.12]
[MSG:INFO: Axis X (-1000.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     stepstick Step:gpio.26 Dir:gpio.16:low Disable:NO_PIN]
[MSG:INFO: Axis Y (-1000.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     stepstick Step:gpio.25 Dir:gpio.27 Disable:NO_PIN]
[MSG:INFO: Axis Z (-1000.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     stepstick Step:gpio.17 Dir:gpio.14:low Disable:NO_PIN]
[MSG:INFO: Axis A (-1000.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     stepstick Step:gpio.19 Dir:gpio.18 Disable:NO_PIN]
[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]

Grbl 3.9 [FluidNC v3.9.1 (wifi) '$' for help]
   

##########################
# second startup message #
##########################

ets Jul 29 2019 12:21:46

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff0030,len:1184
load:0x40078000,len:13260
load:0x40080400,len:3028
entry 0x400805e4
[MSG:INFO: uart_channel0 created]
[MSG:RST]
[MSG:INFO: FluidNC v3.9.1 https://github.com/bdring/FluidNC]
[MSG:INFO: Compiled with ESP32 SDK:v4.4.7-dirty]
[MSG:INFO: Local filesystem type is spiffs]
[MSG:INFO: Configuration file:config.yaml]
[MSG:INFO: Machine Rotodactyl]
[MSG:INFO: Board Wemos D1 mini]
[MSG:INFO: Stepping:RMT Pulse:4us Dsbl Delay:0us Dir Delay:0us Idle Delay:255ms]
[MSG:INFO: User Digital Output: 0 on Pin:gpio.2]
[MSG:INFO: User Digital Output: 1 on Pin:gpio.4]
[MSG:INFO: Axis count 3]
[MSG:INFO: Shared stepper disable gpio.27]
[MSG:INFO: Axis X (-1000.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO:     stepstick Step:gpio.25 Dir:gpio.32 Disable:NO_PIN]
[MSG:INFO: Axis Y (-1000.000,0.000)]
[MSG:INFO:   Motor0]
[MSG:INFO: Axis Z (-1000.000,0.000)]
[MSG:INFO:   Motor0]
[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]

Grbl 3.9 [FluidNC v3.9.1 (wifi) '$' for help]

User Interface Software

FluidTerm, custom python program

What happened?

I create two gcode files with the same amount of moves. All moves are G93 inverse feedrate moves and have the same duration.
The only difference is that one file has four axes and the other has only one. At the begin and ending of both programs I toggle a user output pin to measure timing between the two controllers with my oscilloscope. I upload the files to the controllers via xmodem and start them with $LocalFS/Run=moco.nc . I send the start command to both controllers via custom python code. The first pulse that indicates the start of the program has a deviation of about 2ms between controller 1 and controller 2. The second pulse has as a deviation of 1.3 seconds between controllers. The whole program runs for 7.1 seconds on controller two, executing 200 moves. Each move should take 41.7ms (1/24 s). All moves should therefore take 8.33s .
Controller one finishes correctly in 8.3s.

GCode File

first gcode file

G94
G0X0.00Z89.00Y-90.00A100.00
G93
M62 P1
G4 P0.1
M63 P1
G1X0.00Z89.00Y-90.00A100.00F1440.00
G1X0.00Z89.00Y-90.00A100.00F1440.00
G1X0.35Z89.00Y-90.00A100.00F1440.00
G1X0.70Z89.00Y-90.00A100.00F1440.00
G1X1.06Z89.00Y-90.00A100.00F1440.00
G1X1.43Z89.00Y-90.00A100.01F1440.00
G1X1.81Z89.00Y-90.00A100.01F1440.00
G1X2.19Z89.00Y-90.00A100.02F1440.00
G1X2.57Z89.00Y-90.00A100.02F1440.00
G1X2.97Z89.00Y-90.00A100.03F1440.00
G1X3.37Z89.00Y-90.00A100.04F1440.00
G1X3.77Z89.00Y-90.00A100.05F1440.00
G1X4.18Z88.99Y-90.00A100.06F1440.00
G1X4.60Z88.99Y-90.00A100.07F1440.00
G1X5.02Z88.99Y-90.00A100.08F1440.00
G1X5.45Z88.99Y-90.00A100.09F1440.00
G1X5.88Z88.99Y-90.00A100.11F1440.00
G1X6.32Z88.99Y-90.00A100.12F1440.00
G1X6.76Z88.99Y-90.00A100.14F1440.00
G1X7.21Z88.99Y-90.00A100.15F1440.00
G1X7.66Z88.99Y-90.00A100.17F1440.00
G1X8.12Z88.99Y-90.00A100.19F1440.00
G1X8.58Z88.99Y-90.00A100.21F1440.00
G1X9.04Z88.99Y-90.00A100.23F1440.00
G1X9.52Z88.99Y-90.00A100.25F1440.00
G1X9.99Z88.99Y-90.00A100.27F1440.00
G1X10.47Z88.99Y-90.00A100.29F1440.00
G1X10.96Z88.99Y-90.00A100.31F1440.00
G1X11.44Z88.99Y-90.00A100.34F1440.00
G1X11.94Z88.99Y-90.00A100.36F1440.00
G1X12.43Z88.99Y-90.00A100.39F1440.00
G1X12.93Z88.99Y-90.00A100.42F1440.00
G1X13.44Z88.99Y-90.00A100.44F1440.00
G1X13.95Z88.99Y-90.00A100.47F1440.00
G1X14.46Z88.98Y-90.00A100.50F1440.00
G1X14.97Z88.98Y-90.00A100.53F1440.00
G1X15.49Z88.98Y-90.00A100.56F1440.00
G1X16.02Z88.98Y-90.00A100.60F1440.00
G1X16.54Z88.98Y-90.00A100.63F1440.00
G1X17.07Z88.98Y-90.00A100.66F1440.00
G1X17.61Z88.98Y-90.00A100.70F1440.00
G1X18.14Z88.98Y-90.00A100.73F1440.00
G1X18.68Z88.98Y-90.00A100.77F1440.00
G1X19.23Z88.98Y-90.00A100.81F1440.00
G1X19.77Z88.98Y-90.00A100.84F1440.00
G1X20.32Z88.98Y-90.00A100.88F1440.00
G1X20.88Z88.98Y-90.00A100.92F1440.00
G1X21.43Z88.98Y-90.00A100.96F1440.00
G1X21.99Z88.98Y-90.00A101.00F1440.00
G1X22.55Z88.98Y-90.00A101.05F1440.00
G1X23.12Z88.98Y-90.00A101.09F1440.00
G1X23.69Z88.97Y-90.00A101.13F1440.00
G1X24.26Z88.97Y-90.00A101.18F1440.00
G1X24.83Z88.97Y-90.00A101.22F1440.00
G1X25.41Z88.97Y-90.00A101.27F1440.00
G1X25.99Z88.97Y-90.00A101.32F1440.00
G1X26.57Z88.97Y-90.00A101.36F1440.00
G1X27.15Z88.97Y-90.00A101.41F1440.00
G1X27.74Z88.97Y-90.00A101.46F1440.00
G1X28.33Z88.97Y-90.00A101.51F1440.00
G1X28.92Z88.97Y-90.00A101.56F1440.00
G1X29.52Z88.97Y-90.00A101.61F1440.00
G1X30.12Z88.97Y-90.00A101.66F1440.00
G1X30.72Z88.97Y-90.00A101.72F1440.00
G1X31.32Z88.97Y-90.00A101.77F1440.00
G1X31.92Z88.97Y-90.00A101.83F1440.00
G1X32.53Z88.97Y-90.00A101.88F1440.00
G1X33.14Z88.96Y-90.00A101.94F1440.00
G1X33.75Z88.96Y-90.00A101.99F1440.00
G1X34.36Z88.96Y-90.00A102.05F1440.00
G1X34.98Z88.96Y-90.00A102.11F1440.00
G1X35.60Z88.96Y-90.00A102.17F1440.00
G1X36.22Z88.96Y-90.00A102.23F1440.00
G1X36.84Z88.96Y-90.00A102.29F1440.00
G1X37.47Z88.96Y-90.00A102.35F1440.00
G1X38.10Z88.96Y-90.00A102.41F1440.00
G1X38.73Z88.96Y-90.00A102.47F1440.00
G1X39.36Z88.96Y-90.00A102.54F1440.00
G1X39.99Z88.96Y-90.00A102.60F1440.00
G1X40.63Z88.96Y-90.00A102.67F1440.00
G1X41.26Z88.96Y-90.00A102.73F1440.00
G1X41.90Z88.96Y-90.00A102.80F1440.00
G1X42.54Z88.95Y-90.00A102.87F1440.00
G1X43.19Z88.95Y-90.00A102.93F1440.00
G1X43.83Z88.95Y-90.00A103.00F1440.00
G1X44.48Z88.95Y-90.00A103.07F1440.00
G1X45.13Z88.95Y-90.00A103.14F1440.00
G1X45.78Z88.95Y-90.00A103.21F1440.00
G1X46.43Z88.95Y-90.00A103.28F1440.00
G1X47.09Z88.95Y-90.00A103.35F1440.00
G1X47.74Z88.95Y-90.00A103.43F1440.00
G1X48.40Z88.95Y-90.00A103.50F1440.00
G1X49.06Z88.95Y-90.00A103.57F1440.00
G1X49.72Z88.95Y-90.00A103.65F1440.00
G1X50.38Z88.95Y-90.00A103.72F1440.00
G1X51.05Z88.95Y-90.00A103.80F1440.00
G1X51.72Z88.94Y-90.00A103.88F1440.00
G1X52.38Z88.94Y-90.00A103.95F1440.00
G1X53.05Z88.94Y-90.00A104.03F1440.00
G1X53.72Z88.94Y-90.00A104.11F1440.00
G1X54.40Z88.94Y-90.00A104.19F1440.00
G1X55.07Z88.94Y-90.00A104.27F1440.00
G1X55.75Z88.94Y-90.00A104.35F1440.00
G1X56.43Z88.94Y-90.00A104.43F1440.00
G1X57.10Z88.94Y-90.00A104.51F1440.00
G1X57.79Z88.94Y-90.00A104.59F1440.00
G1X58.47Z88.94Y-90.00A104.68F1440.00
G1X59.15Z88.94Y-90.00A104.76F1440.00
G1X59.84Z88.94Y-90.00A104.85F1440.00
G1X60.52Z88.93Y-90.00A104.93F1440.00
G1X61.21Z88.93Y-90.00A105.02F1440.00
G1X61.90Z88.93Y-90.00A105.10F1440.00
G1X62.59Z88.93Y-90.00A105.19F1440.00
G1X63.28Z88.93Y-90.00A105.28F1440.00
G1X63.98Z88.93Y-90.00A105.36F1440.00
G1X64.67Z88.93Y-90.00A105.45F1440.00
G1X65.37Z88.93Y-90.00A105.54F1440.00
G1X66.06Z88.93Y-90.00A105.63F1440.00
G1X66.76Z88.93Y-90.00A105.72F1440.00
G1X67.46Z88.93Y-90.00A105.81F1440.00
G1X68.16Z88.93Y-90.00A105.90F1440.00
G1X68.87Z88.93Y-90.00A106.00F1440.00
G1X69.57Z88.92Y-90.00A106.09F1440.00
G1X70.28Z88.92Y-90.00A106.18F1440.00
G1X70.98Z88.92Y-90.00A106.28F1440.00
G1X71.69Z88.92Y-90.00A106.37F1440.00
G1X72.40Z88.92Y-90.00A106.47F1440.00
G1X73.11Z88.92Y-90.00A106.56F1440.00
G1X73.82Z88.92Y-90.00A106.66F1440.00
G1X74.53Z88.92Y-90.00A106.75F1440.00
G1X75.25Z88.92Y-90.00A106.85F1440.00
G1X75.96Z88.92Y-90.00A106.95F1440.00
G1X76.68Z88.92Y-90.00A107.05F1440.00
G1X77.39Z88.92Y-90.00A107.15F1440.00
G1X78.11Z88.91Y-90.00A107.25F1440.00
G1X78.83Z88.91Y-90.00A107.35F1440.00
G1X79.55Z88.91Y-90.00A107.45F1440.00
G1X80.27Z88.91Y-90.00A107.55F1440.00
G1X81.00Z88.91Y-90.00A107.65F1440.00
G1X81.72Z88.91Y-90.00A107.75F1440.00
G1X82.45Z88.91Y-90.00A107.85F1440.00
G1X83.17Z88.91Y-90.00A107.96F1440.00
G1X83.90Z88.91Y-90.00A108.06F1440.00
G1X84.63Z88.91Y-90.00A108.16F1440.00
G1X85.36Z88.91Y-90.00A108.27F1440.00
G1X86.09Z88.90Y-90.00A108.37F1440.00
G1X86.82Z88.90Y-90.00A108.48F1440.00
G1X87.55Z88.90Y-90.00A108.59F1440.00
G1X88.28Z88.90Y-90.00A108.69F1440.00
G1X89.02Z88.90Y-90.00A108.80F1440.00
G1X89.75Z88.90Y-90.00A108.91F1440.00
G1X90.49Z88.90Y-90.00A109.02F1440.00
G1X91.22Z88.90Y-90.00A109.12F1440.00
G1X91.96Z88.90Y-90.00A109.23F1440.00
G1X92.70Z88.90Y-90.00A109.34F1440.00
G1X93.44Z88.90Y-90.00A109.45F1440.00
G1X94.18Z88.90Y-90.00A109.56F1440.00
G1X94.92Z88.89Y-90.00A109.67F1440.00
G1X95.66Z88.89Y-90.00A109.79F1440.00
G1X96.41Z88.89Y-90.00A109.90F1440.00
G1X97.15Z88.89Y-90.00A110.01F1440.00
G1X97.90Z88.89Y-90.00A110.12F1440.00
G1X98.64Z88.89Y-90.00A110.24F1440.00
G1X99.39Z88.89Y-90.00A110.35F1440.00
G1X100.14Z88.89Y-90.00A110.46F1440.00
G1X100.88Z88.89Y-90.00A110.58F1440.00
G1X101.63Z88.89Y-90.00A110.69F1440.00
G1X102.38Z88.89Y-90.00A110.81F1440.00
G1X103.14Z88.88Y-90.00A110.93F1440.00
G1X103.89Z88.88Y-90.00A111.04F1440.00
G1X104.64Z88.88Y-90.00A111.16F1440.00
G1X105.39Z88.88Y-90.00A111.28F1440.00
G1X106.15Z88.88Y-90.00A111.39F1440.00
G1X106.90Z88.88Y-90.00A111.51F1440.00
G1X107.66Z88.88Y-90.00A111.63F1440.00
G1X108.41Z88.88Y-90.00A111.75F1440.00
G1X109.17Z88.88Y-90.00A111.87F1440.00
G1X109.93Z88.88Y-90.00A111.99F1440.00
G1X110.69Z88.87Y-90.00A112.11F1440.00
G1X111.45Z88.87Y-90.00A112.23F1440.00
G1X112.21Z88.87Y-90.00A112.35F1440.00
G1X112.97Z88.87Y-90.00A112.47F1440.00
G1X113.73Z88.87Y-90.00A112.59F1440.00
G1X114.49Z88.87Y-90.00A112.72F1440.00
G1X115.26Z88.87Y-90.00A112.84F1440.00
G1X116.02Z88.87Y-90.00A112.96F1440.00
G1X116.79Z88.87Y-90.00A113.09F1440.00
G1X117.55Z88.87Y-90.00A113.21F1440.00
G1X118.32Z88.86Y-90.00A113.33F1440.00
G1X119.08Z88.86Y-90.00A113.46F1440.00
G1X119.85Z88.86Y-90.00A113.58F1440.00
G1X120.62Z88.86Y-90.00A113.71F1440.00
G1X121.39Z88.86Y-90.00A113.83F1440.00
G1X122.16Z88.86Y-90.00A113.96F1440.00
G1X122.93Z88.86Y-90.00A114.09F1440.00
G1X123.70Z88.86Y-90.00A114.21F1440.00
G1X124.47Z88.86Y-90.00A114.34F1440.00
G1X125.24Z88.86Y-90.00A114.47F1440.00
G1X126.02Z88.85Y-90.00A114.59F1440.00
G1X126.79Z88.85Y-90.00A114.72F1440.00
M62 P1
G4 P0.1
M63 P1

second gcode file

G94
G0X104.80
G93
M62 P1
G4 P0.1
M63 P1
G1X104.80F1440.00
G1X104.80F1440.00
G1X104.81F1440.00
G1X104.82F1440.00
G1X104.83F1440.00
G1X104.83F1440.00
G1X104.84F1440.00
G1X104.85F1440.00
G1X104.86F1440.00
G1X104.86F1440.00
G1X104.87F1440.00
G1X104.88F1440.00
G1X104.89F1440.00
G1X104.90F1440.00
G1X104.91F1440.00
G1X104.91F1440.00
G1X104.92F1440.00
G1X104.93F1440.00
G1X104.94F1440.00
G1X104.95F1440.00
G1X104.96F1440.00
G1X104.97F1440.00
G1X104.98F1440.00
G1X104.99F1440.00
G1X105.00F1440.00
G1X105.01F1440.00
G1X105.02F1440.00
G1X105.03F1440.00
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M62 P1
G4 P0.1
M63 P1

Other Information

I have tested this with version 3.8.4-pre5 and 3.9.1
If both controllers have the same file, they start and finish at the same time.

The overall delay varies with the number of moves.

The text was updated successfully, but these errors were encountered:

AndreasEpp · 2024-11-06T10:44:14Z

I have tested this now with shorter moves (1/60 s, 1/96s, 1/100s, 1/120s). The overall travel is the same, it is just chopped up into more moves (500, 800, 833, 1000) instead of the original 200 moves at 1/24 s. The result is that the shorter the moves, the smaller the delay between controller 1 and 2. The sweetspot seems to be at around 1/100 s with only 20 ms delay between the two controllers. However the overall duration of the program got more inaccurate with ca 8.6s instead of the 8.3 desired.
At 1/120 s controller 2 finished even after controller 1 instead of the other way around with all the other tests

AndreasEpp · 2024-11-06T13:04:43Z

I think I found an explanation:

Some of the lines in the file are identical because the original motion is so slow. => identical lines get skipped because the machine is already at the position.
because of the slow movement the maximum segment time is reached without planning a step, so a step is performed anyway Problem with Feedrate #772 (comment)

MitchBradley · 2024-12-13T19:08:33Z

Your explanation seems plausible. Is this a practical problem, i.e. do you have a system requirement for motion that slow?

AndreasEpp · 2024-12-14T15:03:50Z

I am building a motion control rig for macro videography you can see here: https://youtube.com/shorts/NohEinu3J5U?si=_9nAc7xaJqgFtQb9

I have tackled the problem by increasing the microsteps of the tmc drivers to 64. This got rid of most of the problem, but it still occurs with ultra slow moves. Right now I am preparing to switch the drivers to UART mode to get them to 256 microsteps.

bdring · 2024-12-14T15:12:07Z

The video looks great. Is that running FluidNC?

This might be part of the problem. We use a timer to control the time between steps. Choosing the timer speed and resolution affects the speed range. If you allow it to go slower it reduces how fast it can go.

We might be able to create an experimental branch that skews the dynamic range to allow slower speeds for you to test.

This is very deep in the code, so it might take some time before we try anything.

AndreasEpp · 2024-12-17T15:22:59Z

Thanks!

Yes, this is running fluidnc-v3.9.1 and it works like a charm.
It's very nice of you to offer but I want people to be able to use stock fluidnc to replicate this.

I don't suppose you could manipulate this with a setting in the config file, because it has to be compiled in, right?

AndreasEpp · 2025-01-10T14:12:35Z

I have now switched my TMC2209s to uart and implemented 256 microsteps which makes the timing problem disappear completely. The only downside is that because of the extra cables I can't close the lid anymore, which I will have to resolve in the next version.

For now, the problem no longer occurs with 64 microsteps or higher.

Is there a way to tell the minimum step time for a single axis?
I imagine for a multi-axis move it would be constrained to the slowest moving axis, but for a single axis it should be straight forward, right?

MitchBradley · 2025-01-10T15:48:05Z

I suspect that you are asking about the segment time, which controls how slow you can go, instead of the minimum step time, which is related to going fast. Each segment needs at least one step. ACCELERATION_TICKS_PER_SECOND, defined as 100 in Config.h, controls that. To change it you would need to recompile the code.

If you want to look at the segment generation code, it is in Stepper.cpp. It is gnarly.

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Problem: G93 timing inaccurate #1372

Problem: G93 timing inaccurate #1372

AndreasEpp commented Nov 6, 2024 •

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AndreasEpp commented Nov 6, 2024

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bdring commented Dec 14, 2024

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AndreasEpp commented Jan 10, 2025

MitchBradley commented Jan 10, 2025

Problem: G93 timing inaccurate #1372

Problem: G93 timing inaccurate #1372

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AndreasEpp commented Nov 6, 2024 • edited Loading

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AndreasEpp commented Nov 6, 2024

AndreasEpp commented Nov 6, 2024

MitchBradley commented Dec 13, 2024

AndreasEpp commented Dec 14, 2024

bdring commented Dec 14, 2024

AndreasEpp commented Dec 17, 2024

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MitchBradley commented Jan 10, 2025

AndreasEpp commented Nov 6, 2024 •

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