7i92 + bob

As I mentioned previously, bad step timings can cause loss of steps.
insufficient direction setup and hold times in particular can cause step
loss at reversals.

As a first step I would double the setup and hold timings and
see if you have the same issue.

PCW wrote:

The dbname1 output give names and I/O pin {dont know whats advantage of this}. 
The advantage is that the "dbname#"  listing gives the names used
on the BOB including the PWM, relay and axis names

Did you look at the limit.home switch pins in halshow to verify that:

1.  They change when you activate the switch by hand
(on that BOB you need to supply external 12V-24V and the
inputs are activated by grounding them)

2.  That  they have the correct polarity (false when not activated)
(you may need to check the invert option in pncconf)

I’m having issues getting my limit switches working on the same setup. I have USB 5V and 24V supplied to the board. I have NC mechanical switches and connected the inputs and their commons to 5V and also tried GND but when I measure their corresponding pin on the DB25 I don’t see any toggling.

Any suggestions? Thanks in advance for your help.

~Mor

Disregard, they work now. I have inputs connected and common to GND. I was trying to probe the BOB directly because I didn’t want to risk damaging the 7i92.

I have everything hooked up now and all XYZ limit switches work when testing with LinuxCNC.

Yes now its working when I choose tandem axis. I dont have any limit switches connected. But tomorrow I want to try new configuration with limit switches. 

During research for open source BOBs for the 7i92 I just stumbled across this thread and are a little baffled.
I didn't even think about using a cheap mach3 bob in combination.

How did you connect the two boards?
I don't assume the pins on the parallel port on the mesa and on the bob are just a match?

Do you still have this working?

I am intrigued!

Yes, all mesa 25 pin FPGA cards are parallel port compatible, 
so most Mach3 BOBs work. There is firmware specifically made
for most common ones.