Author Topic: GRBL settings - axis directions  (Read 597 times)

ccooksey

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GRBL settings - axis directions
« on: October 10, 2016, 10:25:03 AM »
Hey all,

Got my 500mW laser upgraded yesterday with an Eleks L7 that Zax had suggested months ago for PWM (just got the cash and time to do it recently).  After firing it up and also firing up T2Laser, I noted my x-axis was crashing to the left and then realized it was going the wrong way.  My question is this:   What is the difference between step port invert mask and dir port invert mask?  Using 0.9j, so that's $2 and $3, right?

Also, the laser output is not as dark as it was before with the old proprietary, non-Eleks board.  That is using 0 as min, 255 as max.  Time to mess with speeds?

Cory
now: 17x20cm 500mW engraver with Eleks L7 board. 
30x40cm 40W CO2 Chinese laser with bad PS (replacement PS on the way)
future: maybe a 30x40cm 2500mW from Banggood if Black Friday/Cyber Monday deals are good?  :-)

Agastar

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Re: GRBL settings - axis directions
« Reply #1 on: October 10, 2016, 10:30:25 AM »
For the power issue, GRBL 0.9j is 0 - 1000 by default. Try changing the max PWM setting from 1000 to 255 and see if that helps.

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Re: GRBL settings - axis directions
« Reply #2 on: October 10, 2016, 10:38:49 AM »
Welcome to the forum @ccooksey...!!!
Admin -- Ralph -- support @ BenCutLaser dot us
http://www.BenCutLaser.us/BenCutLaserSetup1.8.4a.exe.zip
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via Paypal to bclpp@primemail.com

Zax

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Re: GRBL settings - axis directions
« Reply #3 on: October 10, 2016, 11:37:06 AM »
If you're using T2Laser and installed the J-Tech firmware (following my conversion document) then you can Ctrl-Click the left jog icon to swap the axis direction. J-Tech is set for 0-255 also, so you should be back to normal.

To answer your question, stepper drivers use a direction control pin which can be either high or low input and then the step pulse is either high or low, so using those values sets whether high is + or -. You would usually only change the dir mask, which is exactly what T2Laser does - and you can verify by looking at the Grbl values (Ctrl-Click the Home icon).

Lob0426

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Re: GRBL settings - axis directions
« Reply #4 on: October 10, 2016, 12:47:36 PM »
Use $3 to changes axis directions. See the chart in the page below. A handy page to bookmark.

https://github.com/grbl/grbl/wiki/Configuring-Grbl-v0.9
Richard
A5 2.5W w/homing switches on L7
A5 2W diode self upgraded from stock 500mw

Experimenting with Mega2560 board upgrade

ccooksey

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Re: GRBL settings - axis directions
« Reply #5 on: October 11, 2016, 10:20:14 AM »
Thanks folks!  I didn't have a chance to work with it last night, but it is definitely making more sense now.  Thanks Zax for the Ctrl-Click on the left button bit.  I printed out the T2Laser manual to read in depth.  Probably my power settings will be fixed by the Ctrl-Click on the Send button as well.  Having used the old setup for so long, it's taking a bit of time to figure everything out. 

Cory
now: 17x20cm 500mW engraver with Eleks L7 board. 
30x40cm 40W CO2 Chinese laser with bad PS (replacement PS on the way)
future: maybe a 30x40cm 2500mW from Banggood if Black Friday/Cyber Monday deals are good?  :-)