EPICS Controls Argonne National Laboratory

Experimental Physics and
Industrial Control System

1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  <20162017  2018  2019  2020  2021  2022  2023  2024  Index 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  <20162017  2018  2019  2020  2021  2022  2023  2024 
<== Date ==> <== Thread ==>

Subject: Re: Epics V4 Questions - New to Epics 4
From: Ralph Lange <[email protected]>
To: EPICS Tech Talk <[email protected]>
Cc: "Madden, Timothy J." <[email protected]>, "Veseli, Sinisa" <[email protected]>
Date: Tue, 6 Dec 2016 10:26:10 +0900
Hi Tim,

Answering a specific one of your questions:

On Tue, Dec 6, 2016 at 7:45 AM, Madden, Timothy J. <[email protected]> wrote:
General question:
 I know RPC stands for remote procedure call, but what does it mean in epics V4?
What does it do that epics V3 does not do?

Maybe it is easier to answer in terms of data structures:

"Normal" connections and subscriptions are using a single data type, which may be a structure in V4, but it is fixed during the connection lifetime, and it is the same structure on read, write and subscription operations.

RPC type connections may have different data types on write and read, and the returned structure may change with every call of the method.

Thus, the RPC type connections are well suited to middle-layer type services, where the data written (think: small list of arguments) are very different from the returned values (think: big arrays of structures that depend on the sent arguments).

Cheers,
~Ralph


Replies:
Re: Epics V4 Questions - New to Epics 4 White, Greg

Navigate by Date:
Prev: Re: Epics V4 Questions - New to Epics 4 Andrew Johnson
Next: Re: Epics V4 Questions - New to Epics 4 White, Greg
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  <20162017  2018  2019  2020  2021  2022  2023  2024 
Navigate by Thread:
Prev: Re: Epics V4 Questions - New to Epics 4 Marty Kraimer
Next: Re: Epics V4 Questions - New to Epics 4 White, Greg
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  <20162017  2018  2019  2020  2021  2022  2023  2024 
ANJ, 06 Dec 2016 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· Search · EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·