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Typically, unless you need linear encoder feedback, you can use servo/closed loop drives that
just have local feedback, (no feedback to LinuxCNC) so you don't need encoder inputs, other than
one for the spindle if you want to do spindle synchronized moves.

For a simple system, I would consider a 7I96S or 7I76EU (the main difference is the the 7I76EU has
more digital I/0.) If you are sure you want to add encoder feedback a 7I95T would make more sense,
though you can add an encoder daughtercard to a 7I96S or 7I76EU (7I85/7I89 = 4/8 added encoders)

I am new to the hobby CNC game. I currently have a little 3018that runs GRBL I bought to get my feet wet. My day job is CNC electronics maintenance so I have some experience with industrial controllers. What I would like to do is get a machine running with dual feedback. The biggest issue I have with the little guy is step loss. From what I have found you can run "closed loop" stepper systems which sort of solve the problem but not really so I want to build a system that will do exactly what I want and I was told LinuxCNC and a Mesa controller is the way to go. I have looked at the Mesa site and am thoroughly confused on the options. I see that I'm probably going to want an ethernet connection for real time. I'll have Linux running on a stand alone laptop so I want the controller external. I also know I'll need drivers for the servos and power supplies. Which controller and which daughter boards I need are the problem. I will build a 3 axis gantry machine with a slaved pair of Y motors. I would like future expandability options for a 4th axis down the road. I want all 3 axis to run rotary feedback on the motors as well as linear scales for each axis with machine primary positioning done from the scales and compared to the encoders. This is how industrial CNC machines run. Is this something that LinuxCNC and Mesa control boards can handle? If so can anyone help me out with selecting the mesa boards I would need to accomplish this?

A test device would be great. What information do you need to get it to me?

Flex GUI now has HAL I/O controls for a checkable push button, a check box, a spin box and a double spin box.



JT

Borrowed a dongle, TP-Link TP-WN722N, from a Forum Member.

Got an external antenna from another Form Member.

Much swapping and shifting around between bench, cubicle and cabled as far from cubicle as lengths would allow.
Dongle, antenna, 4GB and 8GB, power supplies, LC2.9.2 and LC2.9.4, etc etc
The Dongle works fine, Ebay says $15.

Eventually replaced the monitor on the mill with the one from the bench.
SUCCESS.
Even works in the cubicle with door open without the dongle.

Who would have thought !

Suggestions welcomed on what to do with the faulty monitor.
I am in Kingswood if you want to drop by and take it off my hands.

Thanks to all for the help,
John.

there is already some opencv stuff included:
github.com/multigcs/riocore/blob/main/ri...ons/camjog/camjog.py
 

Solved it myself, had to set sserial_port_0=00xxxxxx

Hello, can I connect both 7i83 and 7i84U to Mesa 7i95t? I need analog output for the spindle and 7i84U for IO expansion. If I connect them both, only the card in the first port gets recognized.

sold

If we are speaking about communication delays, we also have to speak about communication delay between PC and camera.

After all, what is the speed requirement of the belt after all? Is it 0.1m/s? Is it 1m/s?

I use Mesa myself, and my motivation was not to spend hundreds of hours just to save 50 bucks on Mesa.
Mesa is the only turnkey solution here from what I can see that does not require JTAG programmer to start . I wanted to see what options would I have if for some reason Mesa will not be available in some future. I would hate to see it happen, but boy haven't we seen enough world craziness lately.

I admire all the people dedicating their personal time for the common benefit here. 

>>I think the real question is, why arent i mining crypto when my machine has downtime? make the mesa fallback to a crypot miner

how do you know Peter is not doing this secretly while we sleep? 


 

Thanks for your input Langdons.

I used shielded on the encoder feed and analog control lead. The IO's I left unshielded. These looms are wired up and ready to go.

Little bit of progress. Got the control panel assembled with touchscreen and computer. It's definitely not a small screen....
The DB37 breakout units arrived, which will allow me to use the existing Heidenhain control cables to feed the relay board from the Mesa cards.

I just wanted to check VFD speed control wiring. The Delta data sheet only shows external speed control using a potentiometer. Can I wire it like below, using the axis 4 or 5 on the 7i97t to control it?

I'll activate the FWD/STOP, REV/STOP and OUTPUT SHUTDOWN via outputs on the 7i97t.

Thanks!

J

 
 
 
 

The nice thing about linuxcnc is you can call a python program from gcode, have it do whatever you want.... Options are endless really..... Then take that data and keep going.

Ask chatgpt how to do it, it's not that bad takes a bit to setup the m codes, O codes, and python program but is very doable especially with AI now a days

I have the basics built but not completed yet.

Well, tested the card and found no issues.

All inputs read low at 50% of field voltage and high at 65% of field voltage
applied to an input.

Heated to +70C and cooled to -40C and still no issues. Ran at 5V to 32V field
voltage and no issues.

Here is an image of all disconnected inputs in halshow (@ 24V)

 

 

It has a Mitsubishi A800 drive. (I can get the specs tomorrow) It came with 3 900+ page books. I know it receives forward and reverse signals separately. I I'm pretty sure it's PWM, but to me honest, I don't know. Sadly, I didn't build it or configure it. Coming in after someone else kinda stinks.