Newsgroups: comp.robotics
Path: brunix!news.Brown.EDU!noc.near.net!howland.reston.ans.net!usc!news.service.uci.edu!ttinews!waikiki!chu
From: chu@waikiki.tti.com (King-Hang Chu)
Subject: Miniboard Problem - HELP
Message-ID: <1993Jun10.025815.2232@ttinews.tti.com>
Sender: usenet@ttinews.tti.com (Usenet Admin)
Nntp-Posting-Host: waikiki.tti.com
Organization: Transaction Technology, Inc.
Date: Thu, 10 Jun 1993 02:58:15 GMT
Lines: 38


Hi,

   I recently bought a miniboard from Greg and have encountered a
strange problem:

When I first start up the miniboard, every function seems operating. 
I was able to do functions in MON and HEXMON correctly. I tried to
light the LEDs, test motors, read analog and digital ports, etc. with 
no problem.  However, after about half an hour or so, the miniboard
began to ignore my command and I wasn't able to light up the LEDs or
read the analog and digital ports correctly anymore. I still receive
the echo from the HEXMON program as if the command was executed (i.e.
when I type w00ff005d I will get the echo plus the w> prompt back but
the motor LED is not lighted as expected and the motor does not run
anymore. ) When I tried to read the digital and analog port I got
/F instead of FF when nothing is connected to the ports. None of the
chips or components were hot and there were no solder bridges. The
crystal is oscillating and I don't have any clues on what to do except
to wait a few hours and try again.  I found that if I wait long enough
the board will return to normal operation for another half hour and then
going back to the problem state.  I also notice that the LEDs go out one
by one from MTR0 to MTR3 if I left it on and wait for it to crash.

Can someone help me with this problem ?

Thanks in advanced.

King-Hang Chu           email: kingchu@soldev.tti.com or chu@waikiki.tti.com

P.S. My set up is very simple, just a 9V battery hooked up to the power and
     an RS232 25 pin port from an IBMPC hooked up to the Miniboard's RS232
     phone jack with pin 5, 6, and 20 connected on the PC side and pin 2, 3
     and 7 connected to the Miniboard's phone jack.  I am sure the cable is
     hook up correctly, otherwise I wouldn't get this far in testing.


 
