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  2016  2017  <20182019  2020  Index 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  <20182019  2020 
<== Date ==> <== Thread ==>

Subject: Simple channel access write program within Qt
From: "Abdalla Ahmad" <abdalla.ahmad@sesame.org.jo>
To: "tech-talk@aps.anl.gov" <tech-talk@aps.anl.gov>
Date: Tue, 3 Apr 2018 07:36:49 +0000

Hi

 

As part of experimenting with EPICS Qt with EPICS Base 3.14.12.3, I came to the need to write a function that writes values to PVs. Here is my attempt:

 

int status;

chid id;

CA_SYNC_GID gid;

 

ca_search(name, &id);

status = ca_pend_io(1); // Already checking if status != ECA_NORMAL

ca_put(type, id, &value); // type can be DBF_STRING, DBF_DOUBLE, etc.

 

This is already working fine but I have some questions:

1.       I used to have ca_task_initialize and ca_task_exit but my Qt application always crashes on executing the function, the value is written but the app crashes. I thought since CA is already initialized and cleaned-up within EPICS Qt I removed both functions and the app works fine. Is this a correct behavior?

2.       When do I really need the synchronous group version of ca_put(the ca_sg_put)?

 

Best Regards,

 

Abdalla Ahmad

Control Engineer

SESAME

Allan, Jordan.

Tel: (+962-5) 3511348 , ext. 265

Fax: (+962-5) 3511423

Mob: (+962-7)88183296

www.sesame.org.jo

 


Navigate by Date:
Prev: Re: question about pvAccess monitor renato sanhueza
Next: Re: question about pvAccess monitor Marty Kraimer
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  <20182019  2020 
Navigate by Thread:
Prev: Re: question about pvAccess monitor Michael Davidsaver
Next: RE: Simple channel access write program within Qt Abdalla Ahmad
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  <20182019  2020 
ANJ, 09 Apr 2018 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· Search · EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·