On 2/25/2014 7:45 AM, Josiah Morgan wrote:
> I noticed that xylotex has an fpga cape in the works for beaglebone black.
>  (as well as other similar items from other sources)
> I was curious if anyone was looking into the implementation of such fpga
> capes into a linuxcnc build.
> also, what would be the benefits and drawbacks to the addition of this fpga
> module?
> has anyone thought about how linuxcnc would be able to actually take
> advantage of the fpga capabilities?
> I'm just curious because I could see some benefits of possibly allowing the
> fpga to house the kinematics functions as well as drive multiple step pins
> simultaneously.  I just don't know how linuxcnc would command it.
> anyway, I just wanted to bring this up for discussion and see what thoughts
> people had on it.

I've got a logi-bone coming from the Kickstarter project, and will try
and play with the Xylotex board when it becomes available.  I'm also
looking at modifying one of the parallel port Mesa cards to talk
directly to the BeagleBone (vs. trying to do SPI or parallel port
emulation with the PRU).

With all of these, I suspect the easiest path to working systems will be
to get the hostmot2 VHDL code running on the FPGA and modify the hm2 HAL
driver to talk to them.  It's all pretty straight-forward (says the guy
who writes VHDL code for a living and ported the hm2 PCI driver to
user-space).

The general benefits would be the same as switching from software
stepgen to a Mesa card on an x86 system, although perhaps not _quite_ as
dramatic.  The PRU can give you a 2-10x improvement over typical x86
software stepgen (1-10 uS threads vs. 10-25 uS or so), where the Mesa
card is about a 500x improvement (or 20 nS "thread") assuming a 50 MHz
clock.

-- 
Charles Steinkuehler
[email protected]

Attachment: signature.asc
Description: OpenPGP digital signature

------------------------------------------------------------------------------
Flow-based real-time traffic analytics software. Cisco certified tool.
Monitor traffic, SLAs, QoS, Medianet, WAAS etc. with NetFlow Analyzer
Customize your own dashboards, set traffic alerts and generate reports.
Network behavioral analysis & security monitoring. All-in-one tool.
http://pubads.g.doubleclick.net/gampad/clk?id=126839071&iu=/4140/ostg.clktrk
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users

Reply via email to