Stepcraft M700 with 7i92TM

Hello! After fiddling with uccnc on my Stepcraft M700 for a while I thought linuxcnc does look good.

Unfortunately I have lots of troubles to get things up and running.

The uccnc config does not look overly complicated:

Or so I thought. Putting all this in pncconf does leave me with a non-working config, the axes just click when trying to move them. It seems that my machine has swapped dir and step pins but the firmware does not allow that. 

After some trial and mostly error I found this:

- If DB25 Pin 2 is left disconnected ("open"), the spindle starts immediately
- The Y-axis Step signal is on Pin 6, not sure about the Dir 
- The Z-axis Step signal is on Pin 8, not sure about the Dir

But I fail to make sense of it or get anything else to work. Did search through for forum for 7i92 or stepcraft machines, no luck so far. Wrong keywords maybe? Added my config, any help is appreciated!

 

7i92t_benezanx2d.bin firmware will at least have the first 4 stepgen pinouts correct
so that will get you a bit further.

To get the stepcraft configuration fully working may require a  new firmware configuration,
at least to get the PWMgen on the correct pin. Do you have a list of all DB25 pin functions?

yes, that actually helped! Machine is running with a stock cable now and all commands work as expected. Thank you very much!

Except when I shutdown, the spindle starts. That is very uncomfortable. Still trying to understand why this is happening here. Any hints?

Oh and in uccnc the step scale was 160 for xy, 320 for z, here it is 80 for xy and 160 for z. Well, that's not a problem I guess. Maybe loosing some accuracy?

fixed the spindle with a R1000 resistor between pin1 of the db25 plug and ground. all good now!

On a 7I92T you can change the  GPIO  resistors from pullups (default) to pulldowns
to solve this issue (W2 down)