Experimental Physics and Industrial Control System
Subject: |
pyepics problem with PV.put(wait=True) |
From: |
Jameson Graef Rollins <[email protected]> |
To: |
EPICS tech-talk <[email protected]> |
Date: |
Thu, 14 Aug 2014 17:18:35 -0700 |
Hi, folks. I'm seeing what might be a bug in the behavior of PVs in the
pyepics interface, or at the very least something inconsistent with
advertised behavior.
I'm trying to use the wait=True option to PV.put() to wait for process
completion, after which I want to log the put action. Here's a basic
example:
#!/usr/bin/env python
From epics import PV
pv = PV('T1:TEST-SYS_B')
for i in range(10):
pv.put(i, wait=True)
print pv.get()
However, what I'm consistently getting as output from the above is
something like the following:
0.0
0.0
2.0
3.0
3.0
4.0
6.0
6.0
8.0
9.0
Note that the output is not at all what is expected: on three out of ten
writes a pv.get() immediately following a pv.put(wait=True) fails to
return the newly updated value. I see the same failures if I instead
set use_complete=True and check for put_complete==True before issuing
pv.get().
If the put() has actually completed, why is the get() still seeing the
old value?
Thanks in advance for any help or suggestions.
jamie.
Attachment:
pgpfulDjZebXx.pgp
Description: PGP signature
- Replies:
- RE: pyepics problem with PV.put(wait=True) Mark Rivers
- Re: pyepics problem with PV.put(wait=True) Matt Newville
- Navigate by Date:
- Prev:
Re: How to tag soft channels as undefined/disconnected Kellee Summers
- Next:
RE: pyepics problem with PV.put(wait=True) Mark Rivers
- 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
2018
2019
2020
2021
2022
2023
2024
- Navigate by Thread:
- Prev:
RE: ePID deadband on output Mooney, Tim M.
- Next:
RE: pyepics problem with PV.put(wait=True) Mark Rivers
- 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
2018
2019
2020
2021
2022
2023
2024