Re: RE: 802.11 tank control

[adt22-at-drexel.edu]

Steve,
  Thanks for the info.  I'm going to wire up some LEDs and test out the parallel 
port on a couple computers.  I found these links last night:
http://www.xml.com/ldd/chapter/book/ch08.html
http://www.hut.fi/Misc/Electronics/circuits/parallel_output.html

 I hadn't thought of the antenna orientation as a problem, but it makes sense.  I'm 
guessing that it won't be a problem giving controls because the bandwidth and 
precision requirements are low, video is another story.  I'm interested in the 2.3 
gig camera test you did.  What kind of inconsistent results did you get?  I know a 
couple people tried using cameras in one of the battles and they didn't work, I 
thought this was more of a mechanical problem - that the camera was sensitive to the 
bumpy ride?  

 There are a number of robot projects that use 802.11.  But now that I think of it 
the ones I have seen are mostly floor bots.  Once I get my laptop set up with 
wireless ethernet (not so near future) I'll try to do an endurance test.  

 Thanks,
 Amir

----- Original Message -----
From: SteveT44 <SteveT44-at-comcast.net>
Date: Wednesday, February 18, 2004 6:19 am
Subject: RE: 802.11 tank control

> Amir wrote,
> 
> >Right now one of my main questions is: if, inside an infinite
> >loop, I poll for user input and write a byte to the parallel port
> >will the logic be "jumpy".
> 
> Parallel port bits are latched until you write something else to 
> the port.
> At least that's how it worked with 8088's and 286's when I was 
> doing this
> back in the 80's.
> 
> Something I just thought of.  You can get an HP Jetdirect print 
> server with
> one, two, or three parallel ports.  Hooked to a wireless AP, it 
> might solve
> your problem.
> 
> Another thought, 2.3 gigahertz 802.11b bridges may give inconsistent
> connections in a mobile environment.  Every time the orientation of an
> antenna changes, the link will have to reprogram itself to adapt to 
> the new
> geometry.  Results with a 2.3 gig camera system I had was 
> inconsistent.Give it a try though, the wireless network stuff is 
> cheap enough nowadays.
> 
> Steve Tyng
> 
> 
>