5i25 - 7i76 support testers wanted

PCW wrote:

Since you already have a 7I76 I would just not use the CandCNC breakout at all and use the step/dir outputs of the 7I76.
...
Your pinout above cannot be a parallel port pinout (especially with the pin assignment and +12V power)so dont connect anything like this to the 5I25

The problem is that the drives, power supply , and breakout board are already wired up and packed in their original enclosure and I'm trying not to have to rip it open and manually run a bunch of wires directly to the geckos.

As for the +12V power, that's a 12V input to the BOB, so it wouldn't be trying to push that 12V to the 5i25. Also, I'm not sure if that external 12V is needed since the enclosure has it's own internal power supply.

I was hoping to be able to simply configure the pins on the 5i25 and be able to plug in and have motor movement.

Its possible but I expect its a lot more trouble that just re-wireing the BOB
to drive a unsupported BOB you would need:

1. The actual BOB parallel port side pinout (what you showed is not it)
2. A new 5I25 config to match that pinout
3. if you wanted to use pncconf, pncconf would need to be updated to support the new config

Ok, I'm wiring the Geckos directly to the 7i76.

However, I don't seem to be getting any step or direction pulses out of the 7i76 when I try to test an axis with pncconf.

Also, I don't have any lit LEDs on the 7i76 or 5i25, is that supposed to happen? Is field power required for the step/direction signals even if jumper W2 is set to the left (cable power)?

If you dont have any LEDS you wont get step/dir:

There should be 2 yellow LEDS illuminated on the 7I76
The leftmost LED is powered by the local 5V (needed for the step/dir outputs and a few other things) This local 5V normally comes from the 5I25 card (P3 so W2 on the 5I25 must be UP)
and you must have the supplied IEEE1284 cable from P3 on the 5I25 to the 7I76
The 7I76 should also be jumpered for cable power (7I76 W2 in left position)

The rightmost LED is the field I/O power indicator (You need ~12 to 28VDC on TB1 for the field I/O bits to work)

it quite possible the axis text in pncconf doesn't work with the 5i25/7i76 combo. (I can't actually test it)
did you get an error?
try running the finished configuration.

PCW wrote:

If you dont have any LEDS you wont get step/dir:

There should be 2 yellow LEDS illuminated on the 7I76
The leftmost LED is powered by the local 5V (needed for the step/dir outputs and a few other things) This local 5V normally comes from the 5I25 card (P3 so W2 on the 5I25 must be UP)
and you must have the supplied IEEE1284 cable from P3 on the 5I25 to the 7I76
The 7I76 should also be jumpered for cable power (7I76 W2 in left position)

The rightmost LED is the field I/O power indicator (You need ~12 to 28VDC on TB1 for the field I/O bits to work)

Got it working! W2 on the 7i76 was to the left but W2 on the 5i25 was down, fixed that and one of the yellow LEDs on the 7i76 came on (don't have the field power hooked up yet) and the motors move now.

Needless to say I can move the axis way faster and smoother than I ever could in mach.

PCW, what is the minimum current needed for field power? I ask because (before fixing the 5i25 jumper) I tried to hook a 12V 600mA wall wart up for field power and it fried pretty much instantly.

Now, I need to figure out how to slave the 4th axis (A) to the X-axis, since I am driving the gantry from both sides. I know that there's gantrykins that will allow me to use limit switches to square the gantry but I don't know yet how to set that up.

Tomorrow, I'll come back to the shop and try to figure that out along with getting the THCAD set up.

field power with no load should be maybe 30 mA at 12V
Are you sure you didn't have it connected backwards?
(theres a 3A diode to protect the 7I76 in these cases)

Also make sure you have the latest 7I76 manual (V1.9)
there are some pinout errors in earlier versions

Turns out I got confused with the connector being numbered from the bottom so instead of connecting the field power to pins 5 and 8 I actually hooked them it up to pins 1 and 4. Yeah, instantly killed that little wall wart.

Anyway, I got gantrykins set up and the THCAD connected to the encoder input and reporting volts. Before I hook the THCAD to the plasma machine, I noticed that in the manual to the THC comp the author mentions that he had some resistors between the plasma and the THCAD. are these still necessary or was that only because (IIRC) he was using a prototype version of the THCAD?

Now the issue I'm having is getting the GPIO pins working. On the inputs I'm having trouble telling which HAL pin corresponds with which physical pin on the 7i76. Also, in my HAL files I had to comment out any reference to the input pins because it kept saying that those pins could not be found (I'll get the exact error message tomorrow).

The THCAD wiring depends on the THCAD model (-10 or -300) and the voltage you are measureing
some plasma power supplies have pre-divided 0-10V outputs and some do not. If you have a model that provides 0-10V, that connects directly to a THCAD-10. If you have a model with direct plasma voltage output this connects directly to a THCAD-300. If you have a direct (0-300V) plasma output and a THCAD-10 you will need a series resistor


There should be no GPIO pins used at all. The field I/O pins should look like:

hm2_5i25.0.7i76.0.0.input-00
hm2_5i25.0.7i76.0.0.input-00-not
hm2_5i25.0.7i76.0.0.input-01
hm2_5i25.0.7i76.0.0.input-01-not
...

hm2_5i25.0.7i76.0.0.output-00
hm2_5i25.0.7i76.0.0.output-01
hm2_5i25.0.7i76.0.0.output-02

...

If you dont have these pins it indicates an error in communication with the field I/O

this could be caused by <12V field power, VIN jumper wrong, hal/ini file error etc