Separate FPGA pulse length value for each channel?

[FlokiCNC]

Hello,

I am using KFLOP.

Is it possible to set the FPGA step pulse length separately for each channel?

My problem: I am controlling servo drivers which require step pulses at fairly high frequency to get a reasonable speed of the motors. Therefore a short pulse length is necessary. Below 16 bit value to get them to 3000 rpm. And on another axis a Gecko G210 driven stepper, which has a minimum pulse length of 2uS, but with my self made breakout board it works reliably only above 50 bit value of pulse length.

Thanks!

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[FlokiCNC]

Sorry, I solved it. I can leave the FPGA pulse width value to the max 63 bits. I used electronic gear in the Panasonic Servos to get the higher speed from the limited input pulse frequency.

Although, if anybody knows if you can set different FPGA pulse length values to each channel would be nice to know.

[TomKerekes]

Hi FlokiCNC,

The pulse length setting is common to all 8 Step/Dir generators and can't be changed individually.

But I think most Panasonic Drives can accept AB quadrature input. This is individually selectable via the channel number. AB quadrature mode is nice as it avoids pulse length and direction setup time issues and reduces signal frequencies by a factor of four.

HTH
Regard

[FlokiCNC]

Hi Tom,

Thank you for your reply!

Yes, I used the quadrature inputs for the Panasonic drives. I built a custom Breakout board with AM26LS31 differential drivers and AM26LS32 receivers to send step pulses and receive encoder feedback to KFLOP, which were recommended in the driver manual. Only I am not using the encoder feedback in KMotion, as I had some problems with it and haven't had the time to solve it, namely oscillation. But it works ok without closing the loop in KFlop.
Thanks for the great product, it is truly nice