Raspberry Pi CM4 + Mesa 7I80DB-25 + Mesa 7I76 - No response from servomotors

Hello everyone,

I am building a 3-axis cartesian robot with a Raspberry Pi CM4 8Gb, a mesa 7I80DB-25 ethernet board and a 7I76 daughter board. I first tried to configure a single axis with a closed loop Nema24 motor and a CL57T driver, using the Mesa configuration tool, but I can't get any response from the motor.

I am using the 64-bit version of the Raspberry Pi OS with the PREEMP_RT 6.2.0-rc4-rt1 patch, and a recent version of LinuxCNC 2.9.0~pre1 for ARM64 :
Linux raspberrypi 6.2.0-rc4-rt1-v8+ #1 SMP PREEMPT_RT Tue Jan 10 02:13:37 CET 2023 aarch64 GNU/Linux

I attach a latency-test of my system.

I was able to ping the 7I80 and flash the 7i80db_25_7i76x3.bit firmware with MesaCT.
I then created the configuration files for the x-axis (I attach the .hal and .ini files). I had to delete the DPLL timer in the .hal file because it was giving me an error.

The 7I80 is supplied with 5V, connected to the 7I76 with a DB25 cable. The 7I76 is suplied with 24V to the field power (VIN is connected to field power with jumper W1) and get its 5V encoder, step/dir and serial interface power from the 7I80.

Once I run linuxcnc, the /init led of the 7I80 lights up and when I try to move the axis, there is no response from the engine.
I also attach the linuxcnc debug file.

Any help in identifying my issue will be greatly appreciated.
Thanks 

An /init light on a running system means that the watchdog has bitten.

Likely either a real time or watchdog timeout setting error.

Thanks for the answer.

I have tried with different versions of the kernel on the Raspberry Pi CM4 and with an old laptop and the problem happens every time.

When I configure pncconf and try to test/calibrate the axis, the /init led lights up, just like when I run linuxcnc.

I also tried with different Watchdog settings but nothing works.

How can I debug this problem?

Take a look at the tmax values:

halcmd show param | grep .tmax

(these are in ns on ARM)