Subject:
|
Re: Help!! Polaroid problem!!!
|
Newsgroups:
|
lugnet.robotics.handyboard
|
Date:
|
Wed, 22 Apr 1998 01:44:02 GMT
|
Original-From:
|
MAR ERICSON <MAR@COOPER.ihatespamEDU>
|
Viewed:
|
810 times
|
| |
|
|
Why does it seem like everyone except me needs a pullup resistor and
perhaps a capacitor somewhere to operate the Polaroid? I've never had any
problems without any of these components. ???
The first time I connected the sensor, it worked perfectly.
Maybe I my Handy Board happens to have better components? :-/
-----------
ericson mar
Master of Engineering Candidate
Project: Mobile Robotics
mar@cooper.edu
(212)353-4356
Department of Mechanical Engineering
The Cooper Union for the Advancement of Science and Art
-------------------------------------------------------
On Tue, 21 Apr 1998, Darkman wrote:
> Are you using a pullup resistor on the ECHO pin? If not that is your
> problem.
> The ECHO output is an open collector driver which requires an 4.7 K pull-up
> resistor between the output and Vcc.
> The pull-up is necessary for connecting the module to a digital input.
>
> I power mine with a 7805 voltage regulator and it seems to work fine but i'm
> not using it continiously.
>
> The clicking sound is normal.
>
> Another thing I noticed that if I ground the transducer it malfunctions.
>
> I hope that helps , Let me know!
>
>
> -----Original Message-----
> From: Chris Moylan <crm0922@rocketmail.com>
> To: handyboard@media.mit.edu <handyboard@media.mit.edu>
> Date: Tuesday, April 21, 1998 10:46 AM
> Subject: Help!! Polaroid problem!!!
>
>
> > I am trying to use one of the Polaroid 6500 kits from Wirz with my
> > senior design project. It doesn't exactly use a handyboard, but our
> > microcontroller is virtually identical at the lowest level. The problem
> > is when we attach the device to the scope, we NEVER see any significant
> > voltage on the ECHO pin. With the INIT pulsing 5V every second, we
> > still get nothing but residual noise (kind of a lot, but at no more
> > than .5V)and the remnants of the sixteen pulses from the ping. I hear
> > a clicking sound too, which was unexpected and is quite annoying. Is
> > this normal? How come I never have any voltage on ECHO? I am not
> > using the blanking inhibit at all, and if I look at the noise at about
> > a 200mv setting on the scope, I can see a shape in the noise that
> > changes with an objects proximity to the transducer, but it is not
> > anything like a logic level. I have tried a million different ways of
> > hooking this thing up and have tried two different driver boards. I
> > am going to buy another transducer tommorrow, but this is getting
> > ridiculous. How does one go about testing the device? I am powering
> > it with a HP E3631A Triple output DC power supply with the current
> > limiter maxed at 5.0 Amps, which should be enough to cover the 2A
> > pinging surge. Please help me figure out what is going on or a better
> > way to test it. We connected it to the microcontroller as it connects
> > to the handyboard, but that of course didn't work either. If you can
> > respond via email, that would be best because I don't get this list
> > regularly. Please respond soon so I don't fail senior design!! ;-)
> > Take it easy,
> >
> > Chris
>
>
>
|
|
Message has 1 Reply:
 | | Re: Help!! Polaroid problem!!!
|
| well....I might be the way you are powering the sensors ??? Maybe luck ???? :)))))) Actually I don't why you don't need any of those supporting parts. A short question ...For what range are you using the sensors (are you using the binh signal) ?? We (...) (27 years ago, 22-Apr-98, to lugnet.robotics.handyboard)
|
Message is in Reply To:
| | Re: Help!! Polaroid problem!!!
|
| Are you using a pullup resistor on the ECHO pin? If not that is your problem. The ECHO output is an open collector driver which requires an 4.7 K pull-up resistor between the output and Vcc. The pull-up is necessary for connecting the module to a (...) (27 years ago, 21-Apr-98, to lugnet.robotics.handyboard)
|
4 Messages in This Thread:
 
- Entire Thread on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
This Message and its Replies on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
|
|
|
|
