Mesa 7I76EU – Fixing „Unsupported ethernet device – No 7I76EU board found” Error

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SolutionThe issue was an outdated mesaflash version that didn’t support 7I76EU.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
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   mesaflash --version

   My version was too old.
2. Install dependencies (Debian Bookworm):
   bash
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   sudo apt update sudo apt install libpci-dev libmd-dev pkg-config build-essential git

3. Download and compile mesaflash:
   bash
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   git clone https://github.com/LinuxCNC/mesaflash.git cd mesaflash make sudo make install

4. Verify version:
   bash
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   mesaflash --version

   Showed: 3.5.13.
5. Test communication:
   bash
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   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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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.

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

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