Which boards for 6 or 8 axis step/dir outputs with 6 or 8 axis encoder inputs and KConnect

[ebasham]

Hello,

1. To drive eight axes of step/dir with encoder feedback (closed loop), with a number of limit switches and the possibility of encluding analog sensors (pressure and flow) would you recommend a Kflop, 2 snap amps and a Kanalog?

2. Is there a summary table of which connectors on the Kflop map to each of the connectors on the expansion board?

I'm assembling a 5 Axis CNC machine, with 6 motors (6 step/dir outputs and 6 encoder inputs - each drive takes step/dir and has encoder outputs A/B). I'd prefer to have the encoder inputs go to the Kcnc interface so that positional information is available (especially in the case of lost steps). Currently, there are a significant number of limit switches. To interface to the limit switches, I thought the best add-on board would be the Kconnect.

I would like to add two additional step/dir+encoder motors (for the 8 that Kflop is capable of) in the future. I would also like to add linear indicators that send analog of PWM signals back to the Dynomotion control system (i.e. for pressure and flow sensors).

The first 4 Axes are AC Servo Drives

The other axes are NEMA23 5A stepper motors (or possibly a brushed DC motor [BLDC])

I think I might have purchased the wrong hardware.

As I understand it, the Kstep will allow step/dir and encoder operations (for closed-loop control) on 8 stepper motors. However,
- If I add the Kconnect board, then multiplexing to JP6 is not available.
JP7 channels 0-3, JP5 Channels 4-7, JP6 Kconenct, JP2, JP4 free.
- If I add the KAnalog board, then four channels of Step/dir become analog channels for driving Analog Servos, in that case, I recall reading I could add 2 Snapamps to the Kflop with the Kanalog for eight channel step/dir+encoder and analog I/O.

Questions:
re:1. Is this the hardware configuration you would recommend for this application? (Kflop, 2 Snapamps, Kanalog for additional I/O if needed)
re:2 I was unable to find a summary table for what expansion board could be connected to which connectors on the Kflop and Expansion Board. For example, in the manual the Kanalog connector mentions that JP4 and JP9 should be connected to the Kflop, but didn't mention specifically where.
Thanks so much for your help!
Eric

[TomKerekes]

Hi Eric,

It's not common to have so many Step/Dir drives with encoders.

You might be able to use:

KFLOP + 2xSnapAmp + KNozz

KFLOP - would provide 8 Step/Dir Outputs on JP7 and JP5
2xSnapAmps - must connect to KFLOP on JP4 and would provide 8 differential encoder inputs, 16 opto inputs, and 28 3.3V LVTTL IO
KNozz - could connect to KFLOP JP6 and would provide 2 analog inputs

If you need Additional IO KNozz could be moved to spare IO Pins on JP7 requiring a custom cable. 4 IO pins (SPI) are needed for the Analog Inputs to be functional. This would free up KFLOP JP6 for Konnects.