Test if it does it for any field. If so, then I will post out a new one. I have never encountered a failing processor memory but it could be static electricity or just a defect. It would be the first.
Once again I will check it tomorrow, I have the second board here so if this doesn’t work I will put that one in and try that, I’m sure it’s just something I’m not doing right as my knowledge of grbl and any sort of programming was 0 before owning a k40.
I am wondering if the lack of saving the settings is causing this problem though as I have read that you should power cycle for the settings to take effect and as this keeps reverting back to standard settings I’m never going to get a true status reading for the endstops.
No worries Andy, we will work it out together. It should be easy and straight forward. If it reverts then there is something wrong with the board.
@Paul_de_Groot Hello buddy I have been playing again and it seems the settings are being saved which is good but I can not work out why I am having a problem.
With Y endstop activated and sending ? in CNCj if feeds back
Idle|MPos:0.000,0.000,0.000|Bf:15,127|FS:0,0|Pn:Y|Ov:100,100,100
with X endstop activated I get
Idle|MPos:0.000,0.000,0.000|Bf:15,127|FS:0,0|Pn:XZ>
and with both I get
<Idle|MPos:0.000,0.000,0.000|Bf:15,127|FS:0,0|Pn:XYZ>
Am I right in thinking they are working fine and if so what is my next move although I get the same readings if I invert it $5=0 or $5=1.
@Andy_Shilling you might have a defect switch (normally closed) or it is picking up too much electrical noise from the laser power supply which causes all kind of weird behaviour that you cannot explain. The shield has suppression capacitors build in to deal with that. However in your case it might be not sufficient to suppress the noise.
Solution is to buy a 100nF capacitor and solder that to the Y limit switch connections and/or install a shielded cable for that switch or try to re-route the Y limit wires first to see if that makes any difference. Alternatively you can add 100nF capacitor (nano Farad, rated 50Volts) on the power terminals (24V and Gnd, 5V and Gnd). You can buy these capacitors at any Tandy/Radioshack type of store and they cost just a few cents. It’s worth to try these tips.
You can also check whether the problem ceases to exists when you unplug the Y axis motor. Just check the status via “?”. If it ceases that the limit wires are picking up the noise from the Y axis stepper motor (so re-route either of them slightly or pull them away from each other). Let me know if that fixes the issue. If it does please take a photo so we can post that on the K40 forum.
@Paul_de_Groot I’m just off to bed now I just caught your message. Our local supplier over here had just folded so I will order some from eBay, should I go for ceramic or polyester film for the capacitors? I’m guessing either will work.
I actually tried 3 different endstops as I have a few from when I was making my 3d printer but they are all doing the same. I will try the capacitor once they are here, also I will make up a new lead tomorrow and try the X endstop on the pins like the Y to see if that makes any difference.
One thing I would like to ask is why does the “?” For X endstop show XZ but Y only shows Y within the command line?
@Paul_de_Groot I HAVE SUCCESS!!!!!!!!!!!!!
The first board must have a problem, I ended up running a new X endstop signal wire to the pins along with the Y endstop and everything work as it should. So I thought the problem must be the daughter board, I checked continuity and everything was fineright down to the ffc connector on the shield.
I then checked continuity on the shield between pin 8 on the ffc and x signal pin and this was fine so the signal must be getting to the pin as intended but X endstop would not work using the ribbon?
As a last ditch effort tonight I swapped out the board to the second one on my order and run the usual $$ inverts that I need and the thing only bloody works as it should. I have no idea whats going on but for now I have a fully motion functioning grbl shield.
I will let you process this and see if you can understand what has happened and how this other one could possibly be wrong lol.
Hi Andy that’s fabulous. At least you have it working. Let me know if you want me to replace your other board. It would be interesting to understand why that particular limit pin became defect. I test all boards extensively on my k40 to ensure they work well. Let me know So I can ship one out this Monday.
@Paul_de_Groot Thank you, before we jump into replacing this one is there anything I could do like reflash grbl onto it or any other idea you can come up with?
I just don’t understand how/why it will not work when pin 8 and the X endstop pin have continuity. Could it be modified to use the Z endstop pin for the X? I don’t have a Z table so that doesn’t bother me taking up that slot.
Reflashing is complex since this is not a standard arduino. It is a different processor, So you need different libraries in the IDE. Than you need re-assign the limit pins. Next to this, I have not installed a usb bootloader on the processor board because of it’s has a small conflict with the laser output pin. The bootloader toggles the pin on start up which makes the laser flash 3 times shortly. People found this very annoying so I left it off. You still can flash the processor via the in circuit program connector but that requires you to have a programmer like St-link, jtag-ice or usbasp. Both cost about $5 plus the effort of installing the libraries and re-assigning the pins in the cpu-map. It’s all doable for me but if you have not done this before, it’s a bit of a learning process. I am happy to teach you in case you want to do more with that skill otherwise I might as well send you a replacement 
After reading what you have just wrote I think it might be a little to much for me, if you are happy to send me a new one I would be very greatful. I will continue trying with this board for another week just to make sure I’m not doing anything wrong but as its a straight swap for the other I can not see what could be different.
Many Thanks for all your help and hopefully I can give you a better news soon.
@Paul_de_Groot I’ve now got everything as it should but before I fit my refurbished Z table I thought I’d do test run.
It seems my laser isn’t turning off after running a job, this may be because I’m still running LW as though I am using it with the old cohesion board running grbl but are there any settings I should be looking out for?
@Andy_Shilling make sure you configure M5 as the command for turning off the laser in LW.
I thought I had but I’ll double check when I’m home in a few hours, thank you.
@Paul_de_Groot I already had M5 in there just like I suspected, it is strange because the laser doesn’t come on until it is told to but doesn’t turn off?
I have worked out I have to disconnect from LW before the laser will turn off so it seems the M5 isn’t working.
@Andy_Shilling can you try M3 instead? Btw your replacement gerbil is on its way. DHL should have send you a tracking id. If not, let me know and I email you
Thank you kind sir, I look forward to receiving it. I have now tried M3 and that is doing exactly the same. the laser will not turn off until I disconnect the shield from LW.
@Andy_Shilling maybe you can try cncjs and issue the commands manually or stream a tiny gcode program that switches on the laser, draws a line and issues an M5. If that works then we can check which LW config is causing the issue.
@Paul_de_Groot Im not sure how to go about sending a command manually could you give me something to try. I have used cncjs to turn the laser on and off using M4/on and M3/off buttons on the right hand side of the program but this will not work in LW. I think I will try updating it to see if that helps at all.
I’ve just seen the laser test button as well but this is not activating the laser.
Ok I’ve just updated to the latest LW and the first 3 things I cut actually started and stopped as required, then I tried to raster an image and stopped it a little way in and the laser continued to fire.
I am leaning to the board giving this problem because the only way I can stop the laser is to disconnect LW and reconnect it ( the laser will continue to fire until I reconnect LW) or I pull the L wire from the board.
Is it worth me swapping over the shields between these two boards and seeing what happens then?