EPICS Home

Experimental Physics and Industrial Control System


 
2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <20202021  2022  2023  2024  Index 2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <20202021  2022  2023  2024 
<== Date ==> <== Thread ==>

Subject: Opinions please, what should this database do
From: "Johnson, Andrew N. via Core-talk" <core-talk at aps.anl.gov>
To: EPICS core-talk <core-talk at aps.anl.gov>
Date: Wed, 26 Aug 2020 23:16:47 +0000
record(stringin, "si") {
  field(VAL, "This is a string")
}
record(lsi, "lsi") {
  field(SIZV, 80)
  field(INP, "si")
  field(PINI, YES)
}
record(aai, "aai") {
  field(NELM, 100)
  field(FTVL, CHAR)
  field(INP, "si")
  field(PINI, YES)
}
record(waveform, "wf") {
  field(NELM, 100)
  field(FTVL, CHAR)
  field(INP, "si")
  field(PINI, YES)
}

The lsi record's Soft Channel device support copies the string from the si record into the lsi.VAL field through its INP link. You can point an lsi link to either a DBF_STRING or an array of DBF_CHARs and it will handle either type.

Should the aai and waveform records also get copies of that string when they process?

Currently the aai.INP and wf.INP links read the si.VAL field and attempt to parse the string into an 8-bit integer, which they would then use to set the first element of their char arrays. The word “This” isn’t a valid integer, so the parsing fails and both arrays remain empty.

I am considering making changes to the type conversion routines that would make the aai and waveform device supports Do What I Mean in the above cases, at the risk of breaking some very obscure conversions between strings and arrays of char (but not arrays of UCHAR). There would probably be some similar changes in the other direction too.

Any objections? Comments?

- Andrew

-- 
Complexity comes for free, simplicity you have to work for.


Replies:
Re: Opinions please, what should this database do Ben Franksen via Core-talk

Navigate by Date:
Prev: Minor issue with base 7.0.4.1 Mark Rivers via Core-talk
Next: Re: Question from the RTEMS corner Chris Johns via Core-talk
Index: 2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <20202021  2022  2023  2024 
Navigate by Thread:
Prev: Re: Minor issue with base 7.0.4.1 Ralph Lange via Core-talk
Next: Re: Opinions please, what should this database do Ben Franksen via Core-talk
Index: 2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <20202021  2022  2023  2024