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gnea / grbl

An open source, embedded, high performance g-code-parser and CNC milling controller written in optimized C that will run on a straight Arduino
https://github.com/gnea/grbl/wiki
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Grbl don't stop motors after limit switch triggered #1191

Open Dio3L opened 1 year ago

Dio3L commented 1 year ago

Hi, here is my problem : my limit switches are well interpreted by the arduino but it won't stop the motors and we can control it in both directions.

I try to renovate CNC (change old electronic cards) and use it with arduino, tb6600 stepper motor driver and grbl 1.1h version. I use bCNC to control grbl.

My XYZ limit switches are NC so the limit pins are connected directly to 5V and when the switch is trigered, limit pin receive a 0V. I have checked the wiring several times and it is correct, I've tested different configurations and different versions of grbl 1.1 and 0.9 but it never get worked : I still move my motors in both directions when limit switch activated, in each axis. Someone can help me

There is my configuration :

$0=10 $1=25 $2=1 $3=0 $4=0 $5=0 $6=0 $10=1 $11=0.010 $12=0.002 $13=0 $20=1 $21=0 $22=1 $23=0 $24=25.000 $25=500.000 $26=250 $27=1.000 $30=1000 $31=0 $32=0 $100=79.000 $101=79.000 $102=79.000 $110=800.000 $111=800.000 $112=800.000 $120=10.000 $121=10.000 $122=10.000 $130=200.000 $131=200.000 $132=200.000

here, bCNC tell to the right of the 'idle mode' (grbl wait instructions) which switch is activated or not : image

here, just the X limit switch is triggered, Y and Z are free : image

If someone have an idea i can't solve it.

Dio3L commented 1 year ago

I have wired external pull-down for the limit pins.

langwadt commented 1 year ago

$21=0, that means hard limits are not enabled

Dio3L commented 1 year ago

$21=0, that means hard limits are not enabled

The hard limit doesn't work either. I tried with and without hard limit or soft limit I re-upload grbl many times: I tested the correct config and with the default config.h and the default serial configurations but also with differents serial configurations. grbl doesn't stop motors movement when limit pin activated (or disabled if i have a wrong config with $5=0) but it still detects them correctly,.

vlastikcocek commented 1 year ago

do you have a shielded cable for the limit switch?

Dio3L commented 1 year ago

do you have a shielded cable for the limit switch?

I don't have shielded cable for the limit switch, i wired RC filters to reduce the noise but i think i don't need it because arduino detect the two state, high or low correctly and he don't stop the motors anyway.