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<== Date ==> <== Thread ==>
Subject: Re: Lookup table problem
From: Ralph Lange <[email protected]>
To: tech-talk <[email protected]>
Date: Thu, 21 Oct 2010 09:52:38 -0400
On 21.10.2010 08:50, Dalesio, Leo wrote: 
I am not sure if this applies - but the analog input record (and could
be put into the AO record) has support for breakpoint tables. A
breakpoint table with an entry for each integer is a lookup table. There
is some optimization in that code for starting the search for the
segment from the location of the last segment.

Yes, it applies.

The analog output record does support breakpoint tables.

So the two-dimensional feed-forward table could be split up into four one-dimensional breakpoint tables (one for each corrector power supply). These could be used in four ao records that fetch their value from the gap position, and use "Raw Soft" support to write the converted values to the PS setpoints.
Standard tools and records, neither sequencer nor c code or other magic involved.

Breakpoint tables can be reloaded at run time, so should the physicists change the feed-forward tables, you can regenerate and reload the breakpoint tables without rebooting the IOC. (If you use a subroutine record to reload the tables, this can be done by clicking a button.)

HTH,
Ralph

-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Silver
Sent: Thursday, October 21, 2010 4:41 AM
To: tech-talk
Subject: Lookup table problem

hi,

   I need to implement a function for insertion device like this:
   Read a two-dimensions table file from the disk, which is values for
gap positions and Correction coil power supplies (one gap value
corresponding to 4 power supply value). If a gap position is set from
the operator, four power supplies will be set automatically.
I want to use SNC language to do this, for reading the data from disk,
use an asub record for it. Is it ok? Is there any better ways? Did
anyone finish this job before?
   Any suggestions are appreciated.



Best regards
Geyang  2010-10-21

--

Ralph Lange                            Bldg.902-B, Rm.18 tel: x8060
NSLS-II Controls Group                                   fax: x8085

References:
Lookup table problem Silver
RE: Lookup table problem Dalesio, Leo
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