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I would have thought that with "Raspberry PI with GPIO" you would have already had your cheap low-cost HW assisted engine.  If you must use a PC and don't want to find one with a parallel port, low-end Mesa cards are my suggestion (like the 7i92TH or 7i96S).  I think with Remora you'd "get what you paid for" and eventually a low-end Mesa card would be a better bargain, and much more turn-key and supported.
 

Thanks for your response. I realize that an old PC with parallel port works. Counting on an old PC going forward is not something that appeals to me. I also understand that the Mesa card is solid but the price is less than desirable. Noting that I am not an expert, it seems that the Remora with RP2040 over ethernet should be up to the job and be far cheaper than the Mesa cards. Unfortunately,, I don't have the skills to write the SW so the question remains: Is/or will be Remora with RP2040 ready for prime time? Note: currently I have the Raspberry Pi 5 running Linuxcnc using its GPIO port (buffered with some simple buffer HW but not aux processor) and it will probably meet my needs. That said, a solution based on a cheap aux processor would be a big benefit.

There is little more than a single bug fix in 2.10 so unless that is going to affect you which it probably isn't, just get your Mesa card up and running with the working system you have.

The whole point of version 2.9.10 was that the 'single bug' could crash a users machine. So if the 'which it probably isn't,' turns out to be a wrong assumption then it might actually crash your machine if you happen to use existing probing routines.

Thanks very much for your knowledge and advice rodw!

I'm taking it to heart and will NOT update for now.

I'm going to continue posting progress and I hope you'll find it entertaining rather than laughable!

Thanks for the reply. I now also monitored the GPIOs.

Correction to my earlier post in this thread first: the InM is not frozen. That was a monitoring-timing mistake on my end — IN4 (E-stop) tracks perfectly in both inm.00.input-04 and gpio.004.in. Card, InM and Ethernet are all fine.

System: LinuxCNC 2.9.10 (uspace), Raspberry Pi CM5, Debian 12 PREEMPT_RT, 7I96S via hm2_eth.
config="num_encoders=1 num_pwmgens=1 num_stepgens=5 sserial_port_0=0xxxxxxx"

Bank is wired sourcing (common on 0 V) — confirmed by several known-good and working inputs:

E-stop: 24V+ → NC switch → IN4. Released (24 V on pin) → TRUE; pressed (open) → FALSE. Tracks perfectly.
Driver alarms: 24V+ → ALM → IN0–3, working.

Problem input: IN8 has an M8 NPN-NC inductive sensor (sinking). Bare, its target-present level only reached ~13 V, so it read active in both states; I added a ~470 Ω pull-up from the pin to +24 V. The pin now measures:

target absent: 0.1 V
target present: 23.85 V

The sensor's own LED and the card's IN8 input LED both follow the target correctly — but inm.00.input-08 and gpio.008.in read stuck TRUE regardless.

Thanks, heaps, for the info. I have a working config for Ethercat on my raspberry pi 5, So I will play around with connecting a tang 9k to the spi on the pi and see how I go. I will post more info if/when i get it working.
Thanks again.
Andrew

There is little more than a single bug fix in 2.10 so unless that is going to affect you which it probably isn't, just get your Mesa card up and running with the working system you have.

You ought to be able to update straight to 2.9.10 now that you have a working install.

What interfaces / motors does the current setup use? Is it a stepper machine or servos?

If it's a simple stepper machine you could make a start using the hal_gpio module and Pi GPIO pins, but you will need some level-shifting protection as the existing logic is almost cetainly 5V (or 24V) rather than the 3.3V of the Pi GPIO pins.

I just noticed the hal tutorial is not obvious from the earlier link I shared. It is  here . Also explore the rest of the  manual .

Zipdodar wrote:

Hi Group

I would like to potentially use linuxcnc on a Raspberry Pi to program and test steppers and servos

• Are there any solutions that I can see samples of or potential uses that are using a Raspberry Pi or Arduino and LinuxCNC to control and test servo and stepping motors?
  
• One plan is to have a test bench to play with ideas; this will have a controller board, some switches, sliders, connectors for motors, a variable power supply, etc..
  - Could LinuxCNC be used for this? i.e can i program it with Python or similar to run my code snippets or a full program?
  - When connecting motors that use pulse and direction, will I be able to connect any motor as long as the variable power supply is adjusted to give the right power to the motor?
  - Has anyone done this before like this?
  
  
• Another plan is to create individual builds that will have one or more motors, sensors, switches, etc.. and will be all built into a case or item as a stand-alone solution. With a customised touch control screen. So when powered on, it boots up and is ready to use and be controlled from the touch control screen.
  can linuxCNC be used like this?
  if so is ther any links to videos or projects that do similer?
  
  Z
  
  

Sounds similar to some of my customizations. I get, you won't need to run G-code files?

Look at the  hal introduction , and the tutorial that follows. There are several methods of connecting your own custom gui to a stand-alone basic hal config. I tend to use glade. Yes you can then also have the app auto-start, that is configuration in the desktop environment, same as auto-starting any other app at boot.

Yes
Yes
-yes
-yes
-yes, i did, to much for for not much use
Yes

Zipdodar wrote:

I would like to potentially use linuxcnc on a Raspberry Pi to program and test steppers and servos

• Are there any solutions that I can see samples of or potential uses that are using a Raspberry Pi or Arduino and LinuxCNC to control and test servo and stepping motors?
  
• One plan is to have a test bench to play with ideas; this will have a controller board, some switches, sliders, connectors for motors, a variable power supply, etc..
  - Could LinuxCNC be used for this? i.e can i program it with Python or similar to run my code snippets or a full program?
  - When connecting motors that use pulse and direction, will I be able to connect any motor as long as the variable power supply is adjusted to give the right power to the motor?
  - Has anyone done this before like this?
  
• Another plan is to create individual builds that will have one or more motors, sensors, switches, etc.. and will be all built into a case or item as a stand-alone solution. With a customised touch control screen. So when powered on, it boots up and is ready to use and be controlled from the touch control screen.
  can linuxCNC be used like this?

You can build this, but it will be absolutely useless.

Exactly! The PC (raspberry Pi or similar), power supplies and stepper (or servo drivers) can be basically the same. What I think is that the mesa card is not worth it, when you stay with open loop stepper motors and the mechanical system is not made for high speeds. But once you start using the I/O and Encoder inputs it is a real help to have a system that is easy to use, supported and works (happy customer of Mesa Plug n go kit).
For the picoCNC I paid roughly (guessing) 130-140€. Some things come with minimum quantities, others are discounted. It ends up at approx. 30€ a piece +-. I would have just bought the successor of it for 50$, but shipping would have doubled the price. To me it was more about the assembly challenge than the actual need for it. But there are "ready to go" options. 

 


One aspect is that a 10 mm carbide endmill will cost roughly the same. 



 

So for metal working the tooling and material quickly gets in regions where a Mesa card is really my least problem and I bought a 2nd Mesa card after the first one.

#no advertisement just random pictures. 
 

I am not sure if Linux CNC is really cheaper than GRBL. 
 

www.grbl.org/single-post/a-peek-at-the-picocnc This is an example based on the Raspberry Pi Pico, all documented and possible to recreate "in the flesh". I bought the Pico boards for like 3€ a piece. The base board was more expensive, but not too crazy. 

• slow simple 3 axis machine without linear scales or rotary encoders probably works just fine with the GRBL
  • When I think of adding things "slaved axis", "linear scales", "automatic tool changer" I would go for LinuxCNC 
     

Hello All!

More than10 years ago (at that time i just started my studies) my father found a great milling machine in a scrapyard, Prvomajska G301 D1 manufactured in 1973 , the machine seems to be almost not used at all, unfortunately it was subject to weather changes and most of the axis were locked up by rust, its spindle motor and holding bracket broken off and x axis gearbox with motor broken off. Back when he brought it home we started to disassemble, we removed some parts from its quill and then life happened we left it on the field covered with plastic sheets as there was no more space on the workshop. 
Recently we removed some things from the shop and got some place for the mill and we placed it inside, past week we were working very hard to clean up the rest of the machine and mount it back, so far the worst part is that its spindle bearing are quite rusty and once we get the rest sorted out will have to be replaced (altho, i still dont know where we could find it).

Attached are images of before and after cleanup and a picture of a machine we found online.

Couple of decisions weve come up with so far regarding the mechanical parts are as following:
Z-Axis: The Z-Axis has 36mm trapezoidal screw moved through bevel gears from the handle and the nut is bolted on the base of the machine offset by an iron piece, maybe can be seen from a picture when the saddle traverse was removed. Since we couldnt find a neat way to put a ball screw, also, were assuming the ball screw having less friction forces the z axis will just fall down, weve decided to leave the original screw and return back to it if we find any issue later on, following This Old Tony's conversion of his Maho and leaving its Z axis with trapezoidal screw, we're expecting the same...
X/Y-Axis: Both have 28mm trapeziodal screws with anti-backlash nut with pitch of 5mm. The nuts hole on the casting for both sides is 40mm which to our research matches the 25mm ballscrew so it is more or less the driving factor to chose 25mm ballscrews.

Issue #0: Throughout this project we always find it challenging to transport anything to place where we live due to some political issues and locally there is no store that sells parts. One of the solution we've found is a middleman in Germany that transports things to here so more or less we always have to check for delivery to Germany and goods that arent subject to VAT...

Question #1: We plan to travel to a nearby country that has ballscrews however im a little bit confused by Dynamic load rating and Static load rating related to price. A low price offers C(dyn) ~ 1100kgf and C(0) ~ 2700kgf, while a 5 times the low price C(dyn) ~ 1700kgf and C(0) ~ 5000kgf, but a 6 times the low price we can get a C(dyn) ~ 14900kgf and C(0) ~ 41500kgf... I'd appreciate a suggestion if going with the low price option is sufficient, as the 5 times the price seems to not gain much for the added cost and the last option seems like a straight up overkill.. 

Question #2: For the Motors to drive the axis of the machine, were planning to place stepperonline servo motors rated at 1kW ( link ) but interestingly they seem to have EtherCAT servos as well so im  kinda on a edge here.. I was originally planning to go with mesa cards prior to seeing the EtherCAT options, but now i kinda dont mind the added cost for EtherCAT, however, my father hopes to use the machine as a manual mill but he isnt very technophile so we will have to add quite some buttons and dials rather than use the keyboard/mouse to control the machine manually and for this we will need some IO, so, is there any EtherCAT IO that i can daisy chain to the system? I have no experience with EtherCAT so i dont know what im getting into... does LinuxCNC need to support the mentioned drive? Do we have to expect support from the manufacturer for the application? Is it doable?

Question #3: If i was to go with normal drives, i cant really decide on the loop's of the system and therefore the cards. I dont have any experience with Mesa cards, but i do have some experiences with parallel port LinuxCNC and Raspberry GPIO LinuxCNC. Should i go straight to position loop on mesa cards and velocity loop on the drive (hence analog mesa cards) or shall i take it slow and get a step/dir card and later on get an analog card if im happy with it?
Question #3.1:This leads to does Mesa official store shipment to Germany include VAT and complicated transportation or is it simple drop off?
Question #3.2: Can you suggest a good card match up for 4 Axis movement + Spindle + Lots of IO for control panel?

Question #4: Since Servos offer modbus and you can read the position of its absolute encoder im assuming that you can skip the homing procedures on LinunxCNC and fetch position from drives directly, am i correct? 

Question #5: How important is spindle encoder for a milling machine? I cant seem to find a proper place to seat it...

Any suggestion, question or comment welcomed! 

Thanks in advance!