Re:pncconf - feature requests

The latest request was for closed loop stepper configs.
meaning steppers using encoders.

I concur with the request for closed loop stepper configs.

-Thomas

Hear... hear...

( meaning uncontrolled expressions of rapture and joy at the thought that steppers and encodrs will make a baby)

the development version of pncconf allows steppers with encoders. Not that I can test the feature.(I have no steppers with encoders)
I'm just not sure if the newest pncconf will make it into EMC 2.5, I am behind in stabilizing it....

Chris,

I would be happy to set up my machine to try out the stepper with encoders combination.


I am using CNCteknix servo amps which run with step /direction inputs and the encoder is connected directly into the servo amps. In essence the servo amps are a PID controller which drives a BLDC motor.

I would need to design an interface card which would live between a mesa 5i20 card and the three servo amps.

The servo amps have the following 10 pin interface

Pin Label Description
1 RX Input – Serial (5V logic) RX connection for the tuning software.
2 TX Output - Serial (5V logic) TX connection for the tuning software.
3 STEP Input – The rising edge of the step input commands a single encoder step rotation in the direction selected by DIR.
4 DIR Input – A logic high selects a clockwise step and logic low a counter clockwise step.
5 ChA Output – Re-transmission of the encoder Channel A signal to the controller.
6 ENABLE Input – Logic high enables the driver to control the servo motor. Logic low stops all output to the servo motor.
7 ChB Output – Re-transmission of the encoder Channel B signal to the controller.
8 RUN Output – Logic high output indicating the drive is running correctly. If the drive is ENABLE and an error occurs the RUN output will indicate logic low.
9/10 GND Logic ground connection.

I would need to know which connectors on the mesa come into play ( I think this info will be availble in the output from the pncconf utility)in order to design the card.

Additionally the encoders generate homing index pulses the Index pulse is one quadrature resolution wide in duration.

The index pulses are available to me in differential mode so the interface card will also carry receiver electronics along with pulse stretchers to allow correct homing sequence.

Chris, rather than waiting for 2.5 to come out etc if You generate the files, I can then get on with the hardware and trials.

For me this means a quick changeover from working configuration to an experimental one and vice versa.

Andy,

Not a bad suggestion.

I do however make PCBs I hope for living ( www.iconicpcb.com) so its not much of an impost.

Hey Zig.

i could make a sample config.
I need some info though.
i need to know the stepper and encoder scaling.
If you know the scaling great other wise can you give me as much info
in the axis scale screen shot as you can / appropriate.
And how do you control your spindle.