| Re: Realtime in PV-Wave [message #1230] |
Tue, 22 June 1993 00:48 |
oet
Messages: 28
Registered: February 1993
|
Junior Member |
|
|
In article 18JUN199312401085@mars.lerc.nasa.gov, uubrian@mars.lerc.nasa.gov (Brian Bentz) writes:
> Hi everyone,
>
> I'm very new to the group, so I'm not up on what's been discussed
> in the past. However, I'm working on doing some real-time work with
> PV-Wave. I'm curious who all out here on the group have done this kind
> of thing, and what they've done with it. I'm looking for some ideas,(and
> frankly, someone to ask questions because I'm still fairly new to wave
> anyway)
> Brian
I don't know about PV-Wave but in IDL there are several ways to do things like
that. You can run IDL as RPC-Server or RPC-Client. It is possible to provide
running IDL-Severs on distributed Workstations over the whole Internet with real-time
data. Another possibility for nearly-real-time purposes is
updating a display program in IDL with periodically checking an incoming directory
for new data in a background task. This way we distribute Radar- and Satellite
images on our Wide Area Network with 10 Sun Sparc Servers and 160 Workstations.
The images are first distributed to the local area servers and the IDL frontends
on the Workstations then check the NFS mounted incoming directory. On normal
use of the network running animation loops are reorganized and updated when
a new image is in the incoming directory in less than one second.
You can get the current state of our online animation solution via ftp:
ftp ftp.sma.ch (141.249.3.33)
cd /pub/idlmeteo/loop-tool
bin
get Meteo_Anima_2.0a.tar.Z
It is in a working state, so there is to much documentation at this time.
Thomas
--
|Thomas Oettli Internet: Thomas.Oettli@sma.ch |
|Swiss Meteorological Institute thomas.oettli@active.ch |
|Kraehbuehlstr. 58 CServe: 100015.3543@compuserve.com |
|8044 Zuerich |
|
|
|
|
| Re: Realtime in PV-Wave [message #1233 is a reply to message #1230] |
Mon, 21 June 1993 09:47  |
kevin
Messages: 17
Registered: August 1992
|
Junior Member |
|
|
uubrian@mars.lerc.nasa.gov (Brian Bentz) writes:
> I'm very new to the group, so I'm not up on what's been discussed
> in the past. However, I'm working on doing some real-time work with
> PV-Wave. I'm curious who all out here on the group have done this kind
> of thing, and what they've done with it. I'm looking for some ideas,(and
> frankly, someone to ask questions because I'm still fairly new to wave
> anyway) Feel free to post, (or write, if this is such an old topic that
> nobody wants to see it anymore) Thanks!
The best way to go would be to write all of your non-graphic programs in
C or Fortran and interface them to PV wave through a client/server model.
You could write a server in PV wave and run it as a seperate process (the
manual explains how to do this). When your data collection routine comes to
the point where it needs to display data, it can call the server which
would work on displaying the data while your calling function continues
on.
Kevin Anderson
|
|
|
|
| Re: Realtime in PV-Wave [message #1235 is a reply to message #1233] |
Sun, 20 June 1993 19:20 |
rivers
Messages: 228
Registered: March 1991
|
Senior Member |
|
|
In article <18JUN199312401085@mars.lerc.nasa.gov> uubrian@mars.lerc.nasa.gov (Brian Bentz) writes:
> Hi everyone,
>
> I'm very new to the group, so I'm not up on what's been discussed
> in the past. However, I'm working on doing some real-time work with
> PV-Wave. I'm curious who all out here on the group have done this kind
> of thing, and what they've done with it. I'm looking for some ideas,(and
> frankly, someone to ask questions because I'm still fairly new to wave
> anyway) Feel free to post, (or write, if this is such an old topic that
> nobody wants to see it anymore) Thanks!
>
> Brian
> --
> Brian Bentz, Summer Intern
> NASA Lewis Research Center
> MS 142-2
> Cleveland, OH 44135
>
We have been using IDL for real-time data collection for several years
now. The applications include a soft-xray scanning microscope with
real-time image display, a hard-xray trace element microprobe and a
microtomography system.
All of these applications use the CALL_EXTERNAL procedure to call routines
written in other languages (Fortran or C) which actually collect the
data. Structures and arrays are passed to/from IDL to control the data
acqusition and to pass the results back. Most of the applications use
the widget toolkit to build point and click IDL interfaces. The
widget "background" routine does the data display. In IDL 3.1 this is
more flexible since one can define update rates for such background
tasks.
For low data rate applications (<~10 points/second) the data collection
loop can be written in IDL. Higher data rate applications will require
that the individual data points be collected in the external compiled
routines or in hardware.
The adavantage of using IDL or PV-WAVE is the ease of programming and
debugging the hardware and the fact that the data being collected can be
analysed/displayed without invoking another program.
D
D
D
D
D
D
D
For low data rate applications (<10 points/second)
--
Mark Rivers (516) 282-7708 or 5626
Building 815 rivers@bnlx26.nsls.bnl.gov (Internet)
Brookhaven National Laboratory rivers@bnl (Bitnet)
Upton, NY 11973 BNLX26::RIVERS (Physnet)
|
|
|
|
comp.lang.idl-pvwave archive
Members
Search
Help
Login
Home
