allyn@milton.u.washington.edu (Allyn Weaks) (06/29/90)
One of the physics groups here would like some net.advice about the
quickest/best way to do the following task:
They have an experiment, with a little Forth controller board that sends data
to the serial port of a Mac ci. The data rate is low - a 10 byte chunk
(binary) once a second or so. They need an application that will get the
serial data, do some analysis on it, plot it as it comes in, and save
everything to a log file. They hope the analysis will be simple, but until
they get enough data they don't really know - it could end up being fairly
complex. It's essential that no data gets lost, and that the plot doesn't lag
behind reality by more than a second or two. The plot can be simple - axes, a
couple of labels, and the points. Presumably some way to change the scale if
needed. Publication quality plots can be done at leisure from the log files
in Igor or something. So it's a fairly simple task, if there were actually
enough time to give it to a grad student to chew on. But as always, time is a
problem (they need it last week, and really need to have it working by next
week), and the grad student with the most programming experience is needed
desparately for other things.
Has anyone out there done something like this? Not just, "gee it's a simple
problem, just choose a language and write it", but "I've done something like
this and this is how..."
Are there any commercial packages off the shelf that can do this? They're
looking into Lab View and Parameter Manager, and of course the companies say
"of course our application is perfect for your application!", but we haven't
found anyone yet who has actually used these (or anything else). And they're
too expensive to gamble on. Are there any other commercial things we should
look at? (They have to be able to talk to the generic serial port - it if
only talks to it's own fancy controller board, it won't do.)
If they go the route of programming their own from scratch, are there any
suggestions on the quickest way to go about it? So that someone who knows C
but not the Mac can actually have it running in about 2-3 days of work?
Any pointers to sample source code for Think C (4.0 or 3.0) that accesses the
serial ports? Are there commercial add-ons that will do simple plotting? I
do know about Face-It. Has anyone used it? How long does it take to learn?
Does it work on a ci? Is it fast enough to handle 'read serial port, do
calculations, write to file, plot a point' once a second? (I know, depends on
the calculations :-) By any chance is there a plug-in for Igor that reads
the serial port?
Many thanks in advance.
-----
Allyn Weaks
allyn@milton.u.washington.edu sweaks@phast.phys.washington.edu
{backbone}!uw-beaver!milton!allyn sweaks@phast (bitnet)
"That's absurd," objected Milo.
"That may be true, but it's completely accurate, and as long as the answer is
right, who cares if the question is wrong? If you want sense, you'll have to
make it yourself." -- Norton Juster, _The Phantom Tollbooth_