Newsgroups: comp.robotics
Path: brunix!news.Brown.EDU!qt.cs.utexas.edu!yale.edu!spool.mu.edu!mixcom.com!Clint.Laskowski
From: Clint.Laskowski <Clint.Laskowski@mixcom.mixcom.com>
Subject: MY MINIBOARD EXPERIENCES
Organization: Milwaukee Internet Xchange BBS, Milwaukee, WI U.S.A.
Date: Fri, 05 Mar 1993 05:11:30 GMT
Message-ID: <1993Mar05.051130.28196@mixcom.com>
Sender: jjwwjj@mixcom.com (Clint Laskowski)
Lines: 109


Here is a short summary I wrote about my 
MINIBOARD experiences. I am also sending
this to the Robot-Board mail-list. I thought
it might be useful for others who are working
(or are considering working) with the Miniboard.

(I hope I don't come across as an egomaniac for
posting it!)

I'd like to learn more about your experiences
with low-cost microcontrollers and community
projects.

- Clint

-----

MY MINIBOARD EXPERIENCES
by Clint Laskowski

Even before the Miniboard 2.0 was introduced by Fred Martin at MIT, I 
was interested in the idea of low-cost microcontrollers. I had several 
discussions with Fred about building a 6.270 board (the miniboard's 
predecessor, kind of). When discussions for the Miniboard started in the 
comp.robotics newsgroup, I was hooked.

I ordered my PCB from Greg Ratcliff, my CPU from Alan Kilian, and my 
parts kit from Darren Senn. While it did take two months for all my 
parts to arrive, I was kept up-to-date by all my "suppliers." For me the 
longest wait was for my CPU... which of course was not Alan's fault. I 
know others have had problems getting their parts kits from Darren, but 
I did not have this problem. In fact, I got my parts kit long before my 
CPU. It was a bit frustrating to build the miniboard without the CPU. It 
looked impressive, and I felt proud that I took so much care in building 
it, but it couldn't do anything without its CPU.

I took advantage of the time I had while waiting for my CPU to get the 
software I needed from the MIT archives. I use a Macintosh IIci so I 
downloaded the appropriate versions of DLM, MON, and XASMHC11. I use a 
commercial, "BBS"-like, system to access the Internet, so I had to use 
the FTPmail service to get all this software. This is kind of a hassle 
since FTPmail sends most large files (>60K) in chunks which have to be 
reassembled. Suffice it to say I finally got all my software working. 
Next, I assembled my cable and waited for my CPU.

Finally, my CPU arrived! What a great day. I ripped open the envelope 
from Alan, and... wow, was it small! I should have known this, since I 
work with chips all the time and I do have a Motorola 6811EVB, but 
still... after waiting all that time it was kinda silly to open this 
envelope and find a black spec which was suppose to be the answer to all 
my "robot controller" dreams.

Well, I popped the HC11 in the socket, connected my batteries, and it 
worked! I couldn't believe it, first time. I had already written a 
simple, "flash the LED" program and created a downloadable .s19 record. 
I ran it thru DLM, switched my miniboard to "run," hit the reset switch, 
and supprise, it worked! I now had a (expensive -- well, not really) 
microcontroller which could flash an LED on and off once per second!

Next, with some help from Victor Sperry, I downloaded a program called 
Warm'N Fuzzy. This program is the ultimate "miniboard LED flasher." It 
also ran fine.

Next, I played with Fred Martin's HEXMON. I hooked up a low power DC 
motor and controlled its speed and direction using the HEXMON commands.

Most recently I got a hold of Alan Kilian's Servo code. I bought a 
cheap, $18, Futaba servo from the local hobby shop and I have been able 
to get it to rotate by commands from my Mac.

Here is my plan for the immediate future: I just ordered a Tamiya (?) 
Super Blackfoot RC Monster Truck model. I plan to build the kit (eeks!) 
and steer it with the servo I mentioned above. I plan to control its 
drive motor directly with the motor control chips on the miniboard -- or 
if they won't supply enough power, I will go to a RC model electronic 
speed control. I plan to mount the miniboard in the monster truck and 
program it from my Mac (i.e., write source, assemble, download .s19, 
disconnect cable, press reset, get out of the way!). Eventually I hope 
to use a higher level language like small C or some type of subsumption 
architecture like Richard Man's RTX/is (BRET) or Erran Gat's ACTION 
(Erran -- sorry if I messed up your name or the name of your language 
(;-). I also plan to add some sensors. I've got some HP shaft encoders, 
which sound like fun, and a bunch of other "traditional" stuff (bump, 
light, etc...).

Another thought in my plans: should we start thinking about the 
Miniboard III? How about more RAM (Flash!?) and better serial 
communications? Granted, I love the miniboard, but if I can't do some 
subsumption stuff on it, how am I gonna really explore the "cutting 
edge" of hobby/research mobile robots? We got this far on a community 
project, we can go farther [Note: I hope Fred and the rest of the MIT 
gang do not take this as an insult -- rather, I hope they will see their 
efforts have caused me (and others I am sure) to dream of new ideas... 
the miniboard experience has been great and I want it to foster even 
greater community projects!].

That is all! Now that you know about me... why don't you tell me your 
story? Post it so everyone can benefit. See ya.




-- 
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CLINT LASKOWSKI                                           Home:  (414) 571-0739
435 Southtowne Drive, Apt. J-202                    Voice Mail:  (414) 778-7675
South Milwaukee, Wisconsin  53172          Internet: clint.laskowski@mixcom.com
===============================================================================
