Adding A Probe To My Setup | I’ve got questions!

Hi guys, it’s been quite a long time since I have visited or posted here. Once I got Linux Cnc installed and up and running a couple years ago on my fixed gantry mill, it has ran flawlessly ever since. I am really wanting to incorporate a probe into my setup, and I definitely have some questions. Again it’s been a while since I have been into the configuration or anything technical with Linux Cnc so it kind of feels like I don’t know anything lol…I think I will go with the topcom probe because of how low profile it is.  

For some context I have a Mesa 7i76e board and I am currently using Gmocappy. I also have auto tool measurement set up. I found the info to set it up how I want through a forum post on here but don’t remember where it was exactly. On my setup I measure the tool with a digital tool height setter then set that to zero for Z and then use my machine tool setter to get the length of that tool. Every tool thereafter is compensated in length from that first tool. I use an M600 to reset that cycle.  

First question is, if I already have a tool height setter configured as a “probe signal” where do I physically connect the probe on my board and what changes do I have to make in configuration in order to use both simultaneously? 

 There appears to be two options for probing …”work with probe” and “probe screen”…by what I can tell, work with probe should work with gmocappy but probe screen may not. I also see some posts about “work with probe” not working with the newer version of Linux Cnc.  So my question is which works better with gmocappy and are there any clear cut instructions on installing either with gmocappy? 

Third question. It appears that if I Install one of these that the automatic tool measurement will be utilized differently. I will be using the probe to find the workpiece then also using the probe to find the height of the tool setter. Then each tool length is compensated from there. Can I do it this way while also being able to do it the other way if I want, or will they conflict with each other? I’m assuming they will conflict because the M6 command will be mapped to one method or the other (I think). Also, currently after I find the length of the first tool that tool length remains until I run a M600. In other words, I can run programs individually without having to do tool changes within one program and the tool length compensation stays indefinitely until the M600 is given. Will this behavior be the same with the new probe method, or will it only work within one program? This would be a major downside as I currently have to and prefer to split up programs individually by tool.  

 I’m sure there’s more info and clarification needed, but hopefully this gets my questions across and gets me headed in the right direction. I appreciate any and all help! Thanks, Andy    

It seems you are asking how to connect both a touch probe and tool setter to your machine. There are multiple ways of doing this. Possibly the simplest would be to connect them both to the same input. You would wire them in series if they are normally closed switch signals, or in parallel if normally open. Alternatively you can connect them to different inputs and combine the signals via hal logic (or2 or and2) and send the hal logic output to the probe input pin. The advantage of using two separate inputs and hal logic would be switch type would be irrelevant, and you could easily add/remove or disable/enable one or both of them as needed.

andypugh wrote:

Gmoccapy has built-in tool length measurment support, so you probably followed the instructions here when you set it up:

linuxcnc.org/docs/stable/html/gui/gmocca...uto-tool-measurement

This uses the motion.probe-input pin already, so you _might_ just be able to wire your touch probe in series with the tool height setter and that will just work. Or not....

For this to work the touch-probe would need to be permananetly wired and both probes would be of the break-on-contact type.

Gmocappy is broken in 2.9 on Bulseye and above, so 2.8 only until th ematter is resolved.

Is it still broken?

I was watching Sliptonic's video on Tool Setup and saw he uses Gmocappy, I also have a touch screen on my rig, so I was working on switching to gmocappy while also figuring out how to wire up an xyz probe... until I found this post.

(His video: )

Rod, is it still broken? {And man, you are everywhere }

I  have no  idea. I suspect gmocapy is  now unbroken.