Moving Gantry router with 6i25

Hi,

I just bought a 6i25 to drive the stepper motors (through a G540) on my moving gantry router. However, I have a problem because I have two stepper motors (one on each side) to move the gantry.

I think normal operation shouldn't be a problem - I can just run two hardware steppers in lock step. However, I'm not sure how to do homing.

Currently -with software stepping- I keep both sides in lock step until one side hits its limit switch. I then step the other side until it hits its limit. In a similar manner,I back both sides off from the limit switches. From then on, both motors move in lock step.

The HAL code to do this uses AND gates to block or pass the STEP signals based on limit switch logic. When I move to HW step generation, can I use the ENABLE pins on the step generators to accomplish the same thing?

TIA,
Tom

Hello,

Have you tried gantrykins?

www.linuxcnc.org/docs/html/man/man9/gantrykins.9.html

Rick G

Rick,

I looked into gantrykins when I first set up the router. Information I got from CNCZone and other sites seemed to indicate it didn't home properly. But looking at the link you provided, it seems that it does.

I can give it a try, but do you have any experience using it with hardware step generation?

Thanks,
Tom

Tom,

To be honest I do not use gantrykins on my gantry router basically because my set up does not have home switches and was set up several years ago before gantrykins was around.
"if it's not broken don't fix it."
I have a solid stops at the park positions and always end with a g53 move to home. When I start the machine I just need to make sure both gantry sides are against their stops.

I can't think of any reason hardware step generation would make any difference in your case.

As you sorted out your hal with your original system you should be able to do the same with hardware step generation.

Rick G

I started looking at using gantrykins with my current software-based setup. And got very confused...

Until I realized that the only way anything made sense was if 'Axis' in HAL really meant 'joint'. And according to the HAL Integrator's Manual, 'Axis" does mean 'joint. Very confusing after reading the kinematics description!

Anyway, using gantrykins is a lot clearer now.

Thanks,
Tom

Glad to hear you are getting it sorted out. Let us know how it all works out.

Rick G

Thanks. This forum is turning out to be very useful.

I'm now having trouble getting hm2_pci to initialize. But I see that 2.5.1 has just been released, and claims to have a fix for 6i25 problems. So I'm going to update to 2.5.1 tomorrow and see if that helps.

Regards,
Tom

Can you start your computer via a power cycle and see if you get the same problem? 2.5.1 may have 6I25 support but that should not have any effect on the troubles you have since the default 6I25 firmware is
actually 5I25 firmware so the card "looks" like a 5I25

Also to check things can you download the 5I25 zipfile from www.mesanet.com and extract the utility rpo from /utils/linux. You will have to chmod the utilty to make it executable:

chmod +x rpo

and the run this command:

./rpo 100

and report the results

Thanks

PCW,

You are right. 2.5.1 didn't help. Also, power cycling doesn't help.

I ran rpo, and the result is 0xFFFFFFFF, the same value LinuxCNC complains about. See this snippet from dmesg:

[ 789.047380] hm2: loading Mesa HostMot2 driver version 0.15
[ 789.062155] hm2_pci: loading Mesa AnyIO HostMot2 driver version 0.7
[ 789.062547] ACPI: PCI Interrupt Link [LNEA] enabled at IRQ 17
[ 789.062553] alloc irq_desc for 17 on node -1
[ 789.062555] alloc kstat_irqs on node -1
[ 789.062567] hm2_pci 0000:03:00.0: PCI INT A -> Link[LNEA] -> GSI 17 (level, low) -> IRQ 17
[ 789.062581] hm2_pci: discovered 5i25 at 0000:03:00.0
[ 789.062767] hm2/hm2_5i25.0: invalid cookie, got 0xFFFFFFFF, expected 0x55AACAFE
[ 789.062772] hm2/hm2_5i25.0: FPGA failed to initialize, or unexpected firmware?
[ 789.062775] hm2_5i25.0: board fails HM2 registration
[ 789.062787] hm2_pci 0000:03:00.0: PCI INT A disabled
[ 789.062794] hm2_pci: probe of 0000:03:00.0 failed with error -22
[ 789.321233] hm2: unloading

Mesa tech support suggested reloading the flash if 2.5.1 didn't correct the problem. Do you think that's what I should try next?

Thanks,
Tom