7i96 Configuration Tool

I did remember that i had to do that once a while back and "yes" did not work, but 1 did.
Glad i remembered correctly.

There seems to be a bug in my system.

I flashed using the tool and the 4 stepgen and 1 PWM. On opening LCNC there were no manual spindle button controls.

I added some HAL as documented in the spindle section of the DOC's and the buttons showed up but clicking on them does nothing to the voltage at the PWM plus and minus pins on the 7i96 which stays at -5v.

Jools

Just tried a brand new configuration to see if I'm going nuts and it threw an error on start up saying

pin 'motion.spindle-forward' does not exist.

I have communicated with my card using the other pinned thread about setting the connection.

It has the 5 step gen from what I can see from the read button.

Is it as simple as selecting 4 steps gen with pwm and clicking flash?

ETA It appears so

Leon82 wrote: I have communicated with my card using the other pinned thread about setting the connection.

It has the 5 step gen from what I can see from the read button.

Is it as simple as selecting 4 steps gen with pwm and clicking flash?

ETA It appears so

Leon

Read this thread to get it working properly. forum.linuxcnc.org/38-general-linuxcnc-q...et-pwm-output-solved

Jools

jools wrote:

Leon82 wrote: I have communicated with my card using the other pinned thread about setting the connection.

It has the 5 step gen from what I can see from the read button.

Is it as simple as selecting 4 steps gen with pwm and clicking flash?

ETA It appears so

Leon

Read this thread to get it working properly. forum.linuxcnc.org/38-general-linuxcnc-q...et-pwm-output-solved

Jools

Yes I have it bookmarked.did you post the pwm Hal section?

will do now but there seems to be further issues, though again this may be my lack of knowledge. I'll ask PCW and John but it involves the servo overspinning, I think it's a feedback thing from the encoder.

Just to document the issue I'm having after enabling PWM.

The servo spindle that is controlled by the PWM revs up to it's hard limit even at low voltages due to the motor not being under load. So when inputting a low spindle speed of say 1000 rpm it would spin up to the hard limit of 2500. When it starts cutting and the motor goes under load it would then drop it's speed level accordingly.

Is there a way this can be monitored with feedback commands or something similar so that so the spindle speed is limited by linux cnc?

Yes, this is a perfect application for a PID controller.

There is an example here: wiki.linuxcnc.org/cgi-bin/wiki.pl?Closed...pindle_Speed_Control

But it isn't a very good one.... It adds the PID output on to the spindle speed command. I presume this is because it is old and dates to a time before the PID component included feed-forward terms.

Basically:
spindle-speed-command => PID command
spindle-speed-feedback => PID feedback
PID-output => PWM value

(ie, the PID is inserted between the spindle command out and the PID command in)

Start with P, I, D all zero and adjust FF0 to give the right speed under no-load. Then adjust I (mainly) and some P to get good stiff speed control.

Be aware of units. Use a revs-per-second spindle speed command, as encoder velocity is in revs-per-second.

Hey, didn't you add the velocity-rpm pin to the software and HM2 encoder?

That simplifies the PID setup

PCW wrote: Hey, didn't you add the velocity-rpm pin to the software and HM2 encoder?
That simplifies the PID setup

True, I did. But it isn't there on all LinuxCNC versions. .