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For basic step/dir servos, a 7I76EU should do (by itself)

The 7I76EU has:

5 axis of step/dir outputs
32 digital inputs (5 to 24V)
16 digital outputs (5 to 24V)
Isolated analog 0..10V output for VFD spindle speed control
encoder input for spindle synchronized motion
2 parallel expansion ports (for additional step/dir or encoder channels)
1 serial expansion port (for more digital I/O

 

i asked ChatGPT about the boards, and it said I should use the 7i76e for axis control, the 7i85 for secondary axes, and the 7i89 for encoders.
Is this configuration correct?I also want to add some information about the servo motors I'm planning to buy.
I don't fully understand all the technical details, but if there is anything wrong or incompatible, I would really appreciate it if you could let me know.
Thank you!  

drive.google.com/file/d/1As0Eivp9ck6G0jz.../view?usp=drive_link
 

PCW wrote:

Yes, a fairly ancient version of mesaflash (3.4.9)  is included with the
LinuxCNC 2.9.4 ISO, this is supposedly fixed for later releases.

I don't think mesaflash is included in V 2.9.4 in our ISOs because it is seperate to Linuxcnc and has its own Deb file.
If that is the case, 2.9.4 will just get the very early version in the Bookworm repo.
Perhaps Our Debian build system should be modified to  make mesaflash so it gets stored in our repos

Yes, in most cases, mesaflash is not needed as the installed firmware is sufficient.
 

Yes. Current stable version 2.9.4 ISO
I think that mesa and linuxcnc card experts may not have even noticed this. because they either knew where and how to download the updates without a problem. or they skipped this step altogether and did the configuration right away.

Yes, a fairly ancient version of mesaflash (3.4.9)  is included with the
LinuxCNC 2.9.4 ISO, this is supposedly fixed for later releases.

Was this with the version included in the 2.9.4 ISO?
Djakuju bardzo.

ProblemAs a newbie to Mesa cards, I spent a whole night trying to connect to a 7I76EU card (IP 10.10.10.10, jumpers W2=OFF, W3=OFF). mesaflash kept throwing errors: „Unsupported ethernet device 7I76EU” or „No 7I76EU board found”, even though ping to 10.10.10.10 worked and LEDs CR4 (FIELD POWER) and CR14 (LOGIC POWER) were on. CR11 (FIELD I/O FAULT) was lit, and CR13 (FPGA /DONE) sometimes lit up, hinting at a firmware issue. I wasn’t sure whether to use 7I76EU or 7I76E in commands, as 7I76EU is less common.What I checked

• Power: Connected 24V DC to TB1 (VIN) and TB2 (FIELD POWER), following: YouTube: Mesa 7I76E Power . Jumper W1=ON. Did not use P4/P5 (5V) as the card has built-in regulators.
• Network: Used a standard Ethernet cable (non-crossover), connected directly to PC. Initially tried IP 192.168.1.121 (W2=ON, W3=OFF), but switched to 10.10.10.10 (W2=OFF, W3=OFF), setting up the network per: Forum: Mesa Ethernet Setup . PC IP was 10.10.10.11/24, firewall disabled (sudo ufw disable).
• mesaflash attempts: Commands like sudo mesaflash --device 7i76eu --addr 10.10.10.10 --readhmid failed. I noticed the error mentioned „7I76EU” even when I used ETHER or 7i76e, suggesting the card was detected but not supported by mesaflash.
• LinuxCNC: Using Pncconf, I configured for 7I76E (IP 10.10.10.10). Changing INI to BOARD=7I76EU caused LinuxCNC to fail, but BOARD=7I76E worked, and CR11 turned off. On TB2, a multimeter showed DIR+5V signals changing with axis movement, and shorting IN17 to +24V activated the input in HAL. The card was working!

SolutionThe issue was an outdated mesaflash version that didn’t support 7I76EU. Updating from GitHub fixed it. Steps:

1. Check version:
   bash
   Copy

   mesaflash --version

   My version was too old.
2. Install dependencies (Debian Bookworm):
   bash
   Copy

   sudo apt update sudo apt install libpci-dev libmd-dev pkg-config build-essential git

3. Download and compile mesaflash:
   bash
   Copy

   git clone https://github.com/LinuxCNC/mesaflash.git cd mesaflash make sudo make install

4. Verify version:
   bash
   Copy

   mesaflash --version

   Showed: 3.5.13.
5. Test communication:
   bash
   Copy

   mesaflash --addr 10.10.10.10 --device ETHER --readhmid

   After fixing a cable mix-up, it returned card details: BoardName: MESA7I76, HostMot2 firmware, 5 StepGen, 3 I/O ports.

Notes

• Ensure the PC is in the 10.10.10.x/24 subnet and firewall is disabled.
• Jumpers W2=OFF, W3=OFF set IP 10.10.10.10; W2=ON, W3=OFF sets 192.168.1.121.
• LinuxCNC with BOARD=7I76E works because 7I76EU is compatible with 7I76E in older versions.
• CR13 (FPGA /DONE) stopped lighting up after LinuxCNC started correctly, but updating mesaflash was key for proper diagnostics.

ThanksThanks to advice from LinuxCNC.org , YouTube videos, and Grok’s guidance, I solved the issue. Hope this helps other beginners!
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Hello gentlemen !

Im a Newby and want to run a CNC-mill with a Mesa 7i76E and a Rpi 5.
I have  read the thread and think a RPI 5  with 8 GB will be  the right choice for
bookworm and the mesa. The 16 GB RPI5  won't work or is there any kind of news ?
The freason for the question is that i have to buy a RPI but which one is the best opinion and why ?
Can you help me ?

Thanks   a lot
Ultrakurz
 

It could be a wiring/noise issue but typically this is because of the relatively
instantaneous velocity estimation (typically updated every ms), which tends
to accentuate the encoder inaccuracies. This fast update is important if a feedback
loop is used but a nuisance for a human readable display.

The way this is typically fixed is by low pass filtering the encoder velocity signal
before displaying it. If this has already been done, you might increase the time
constant of the filter

Hey everyone,
I’ve been setting up a CNC mill using LinuxCNC with a Mesa 7i76e board, and I’ve run into a bit of a headache. The spindle RPM readings in the LinuxCNC GUI are fluctuating a lot even when the spindle speed seems stable when measured with an external tachometer. I'm using an encoder on the spindle for feedback, but I’m not sure if the issue is from signal noise, encoder settings, or something else in the HAL config.Has anyone else had similar issues with inconsistent RPM readings? What would you recommend checking first encoder wiring, debounce filtering, or maybe even firmware updates for the Mesa board? Any guidance would be a huge help, I’m still getting comfortable with HAL and custom configs.Thanks in advance!

References:

www.theengineeringprojects.com/2023/06/i...l-with-linuxcnc.html
www.cnczone.com/forums/linuxcnc-formerly-emc2-/
store.mesanet.com/index.php?route=product/product&product_id=58

theslawek wrote:

BINGO, adding the halui line did the trick. Thank you PCW and spumco, you guys are amazing (and lighting fast responders).
 

Thanks for reporting back, and glad to hear it's sorted out.

BTW, the "=>" and "<=" in the line are just characters to help the user visualize the pin to signal connection.  They are not required, and are ignored by LCNC.  I personally find single-line HAL entries nearly impossible to read, but breaking them up in to multiple lines does make for a much longer HAL file.

For example, the single line:
net machine-is-on hm2_7i76e.0.stepgen.04.enable halui.machine.is-on

is the same to LCNC as:
net machine-is-on  <= halui.machine.is-on
net machine-is-on  => hm2_7i76e.0.stepgen.04.enable

After my last post I was trying "machine-is-on" in the lines WITHOUT hm2. I tried your replacement and the result is M3 and M4 no longer do anything. No error.

#net spindle1-enable => hm2_7i76e.0.stepgen.04.enable
net machine-is-on hm2_7i76e.0.stepgen.04.enable

Even tried with the same "=>" and still same behaviour.

Do I have to do something with my regular spindle hal entries for it to play nice?
net spindle-enable => hm2_7i76e.0.7i76.0.0.spinena

PCW wrote:

Simply replacing:

net spindle.1.on hm2_7i76e.0.stepgen.04.enable

with

net machine-is-on  hm2_7i76e.0.stepgen.04.enable

Should fix the issue.
 

PCW - I didn't see the halui signal machine-is-on in his HAL file; maybe I missed it.

OP - if that signal is already in your half file, do what PCW posted.

If it's not already there, you can tweak it to this:

net machine-is-on <= halui.machine.is-on
net machine-is-on => hm2_7i76e.0.stepgen.04.enable

I can confirm this fixed my stepgen spindle after PCW suggested it to me last year.

Simply replacing:

net spindle.1.on hm2_7i76e.0.stepgen.04.enable

with

net machine-is-on  hm2_7i76e.0.stepgen.04.enable

Should fix the issue.