Plasma/Mesa Guru's

I currently have the 7i42TA connected to P4 on the 5i20 and the 7i37TA on the P2.

The stepper outputs are on the 7i42:
Pins 100 and 101 for the X
Pins 106 and 107 for the Y
Pins 1012 and 1013 for the Z

I currently don't have any limits wired, but probably will down the road, and I am currently still using the parallel port for the torch relay and signals as john did.

Heres a bitfile with a more rational pinout for use with a 7I42TA:
freeby.mesanet.com/st8p.zip

the ST8_PLASMA.PIN lists the pinout, note that all high speed I/O is on P2 now (where the 7I42 should be) P3 and P4 just have GPIO .

I also only connected the 'A' pins of the 2 encoder counters present so as not to waste the 'B' or 'I' pins

PCW

Thank you very much. It took me a little bit to figure out where to put those files and how to get them to those folders. But, I got it done and so far it all seems to be working. I will have a chance to rewire the step and dir pins after I send the kids to bed. I did notice that you set the pins to the odd numbers, thank you for that, it will make it extra easy to wire them into place.

With every day on this project I feel like I am learning something new. I like it!

Thank you again everyone for your help, I truly appreciate it.

Looks like I was mistaken.. the odd numbers are actually correspond to pin 100 and 101 then 102 and 103 then 104 and 105. No matter, it wasn't that tough to get the wires in the right places.

Thank you again!

I am getting closer...

I ca go to the HAL configuration screen and see the thc.encoder-vel number change. It is normally at -1902 to -1905 and if I put my little battery pack (3 AAA batteries) I that number jumps to -7230ish

But, still no volts registering on the volt meter (test it button) or in Hal configuration thc.volts

I tried to change some of your parameters thc.vel-scale and thc.correction-vel but non of that seemed to make any difference.

But at least I can see that the THCAD is hooked up and doing something.

Just a side note here, If you use a normal encoder counter, that has both 'A' and 'B' brought out you can reverse the sign of the velocity by changing the polarity of the 'B' input (in up down mode, 'A' is count and 'B' is direction).

In a configuration that only has the 'A' encoder pin brought out, the counter will always count down (because its 'B' input is tied low internally).

Since in this case the counter always counts down, you will always have negative velocity numbers. So you will need to use around -1903 for scale_offset and a negative vel_scale
number.

Yeah! finally Success!

Once I had the scale and offset numbers corrected Volts were looking good. So I tried running the Xtrim file... the Z axis was going completely nuts. I had to go look at the unmodified ini file, that is where I noticed I had already modified the thc.correction-vel to 5000, it was originally .0001 so yeah, the Z was just crazy.

After that was sorted it seems to be working great.

Now I am going to get the relay output, and other inputs moved from the parallel port to the 5i20, make sure all that is working good and go out and hook it onto the torch.

Thank you!

John, the 'Test it' button is on screen, just under the voltage dial. It doesn't seem to do anything though.