Experimental Physics and
Industrial Control System

Pete Jemian via Tech-talk <tech-talk at aps.anl.gov> · Wed, 2 Jun 2021 10:55:59 -0500

Isn't DMA a distinct advantage with running EPICS and FPGA on the same

silicon? Gives hardware-level access to data and allows for interrupts

to the OS from the FPGA.

Pete
(The one who does not program FPGA, just listens to others.)

On 6/2/2021 10:49 AM, Till Straumann via Tech-talk wrote:

Raj.

Regarding network security: most facilities use firewalls and isolated

network segments

for security.

This is orthogonal to your question - EPICS is not particularly secure

(but neither is your

proprietary UDP protocol going to be).

Re. maintenance: yes, you will have to maintain EPICS on an additional

target platform.

However, the zynq/arm target is well supported and I wouldn't expect any

particular

problems. On the upside: you *only* have to support EPICS and won't have

to maintain/support

your proprietary solution in addition to EPICS.

Again: communicating with hardware and providing a standardized

networking interface

(channel-access) is pretty much the definition of an IOC under EPICS.

If IOC system load due to many clients is a concern then that is

traditionally mitigated with

a channel-access gateway.

HTH
- Till

On 6/1/21 11:17 PM, Kunjir, Shriraj wrote:

Hi Till,

Thank you for your response. Could you please elaborate on the

maintenance and network security aspect of such an LLRF controller

when it runs IOC on its PS side Linux?

We are evaluating the potential of running IOC on our Zynq based LLRF

controllers.

*From: *Till Straumann via Tech-talk <mailto:tech-talk at aps.anl.gov>
*Sent: *Tuesday, June 1, 2021 5:09 PM
*To: *tech-talk at aps.anl.gov <mailto:tech-talk at aps.anl.gov>
*Subject: *Re: Advantages of running IOC on FPGA

*[EXTERNAL] This email originated from outside of FRIB*

I'd say that the 'traditionally' an IOC *is* actually executed on a

front-end controller

with EPICS taking care of networking and control-system integration.

This is what

EPICS was originally designed for. (IOCs running on embedded VME

computer that

were directly talking to hardware).

When you don't run an IOC on the Zynq then you have to invent your

proprietary

UDP protocol, write some sort of server that does I/O on the Zynq and

some protocol

translation to EPICS on the 'IOC server'.

FPGA <-> ZYNQ (I/O -> UDP) <-> ethernet <-> server (UDP -> EPICS)

You can eliminate all this effort simply by running an IOC on the zynq.

Cheers
- Till

On 6/1/21 10:14 PM, Kunjir, Shriraj via Tech-talk wrote:

Hello,

Could you please help in understanding the advantages of running IOC

server on LLRF Zynq FPGA over the traditional method of a standalone

IOC server connecting to LLRF FPGA via UDP. Thank you

Raj

--
----------------------------------------------------------
Pete R. Jemian, Ph.D.                 <jemian at anl.gov>
Beam line Controls and Data Acquisition (BC, aka BCDA)
Advanced Photon Source,    Argonne National Laboratory
Argonne, IL  60439                    630 - 252 - 3189
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      Education is the one thing for which people
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Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System