When you have soldered the
header in place, snip off the short
ends of the pins on the top of the
board. You are now ready to install
the DB9 connector. To do so, hold the
stripboard (upside down) in one hand
and the connector (with pins 1
through 5 facing up) in the other.
Insert the board between the two
rows of pins and press them together
so that the five pins on the connector
align with the five traces on the stripboard. (Surprisingly, the pin spacing
on most of these connectors is actually
slightly greater than 0.1”, so the best
approach is to align pin 3 exactly with
the middle trace.)
Figure 6 is a photo of the
completed stripboard as seen from
the bottom. In it, you can see how
the spacing of the DB9 pins is slightly
wider than that of the standard 0.1”
traces. The point of all this is that
when you solder the connector in
place, make sure there are no
accidental solder bridges between the
traces. Finally, you may want to clean
the excess flux from the bottom of
the board. Denatured alcohol and a
toothbrush works well — just make
sure that the board is thoroughly dry
before using it.
may want to download the
new version. It’s available in a
zip file (Tank200905.zip) on
the SERVO Magazine website
( www.servomagazine.com),
along with the TankBot’s 14M
program ( TankBot_IR2.bas),
which has also been slightly
re-commented. Download the
zip file and extract the two
files. To install IR_echo2.bas to
the 08M, make sure the
Prog03 is inserted into the
breadboard as shown in Figure
7, connect your serial cable to
the DB9 on the Prog03, and
you’re ready to go.
I found the revised 08M circuit to
be much more reliable than the original; I now have significantly fewer
false-positive echoes. I think two factors contributed to this improvement:
reducing the number of IR LEDs from
two to one (thereby outputting lower
levels of IR radiation) and increasing
the distance between the IR LED and
the IR detectors (thereby decreasing
the amount of direct IR radiation that
reaches the detectors). I would be
curious to know whether you obtain a
similar result. If you get a chance,
Figure 6. Bottom View of Completed
Prog03 Adapter.
email me at Ron@JRHackett.net.
What’s Next?
As I mentioned before, I’m
already thinking about our next
TankBot project. Actually, I have a
couple of projects in mind, but I would
also like to hear from other TankBot
experimenters. If you have an idea for
a TankBot project that you would like to
see presented here, email me. In the
meantime, have fun with your
TankBot! SV
Using the Prog03
Adapter to Program
the 08M
Figure 7. IR Echo Circuit with Prog03 Inserted.
The pinout of the Prog03 adapter
is designed to minimize the amount of
breadboard space it requires. The Sout
(yellow) and Ground (black) pins can be
inserted into the breadboard directly
adjacent to the corresponding pins on
the 08M. The Sin (green) pin only requires
two short jumper wires to connect it
to the 08M’s Sin pin (see the photo in
Figure 7). To connect the Prog03
adapter to your PC, you can use the
same cable that you have been using
to program the BrainAlpha board.
The program for the 08M
( IR_echo2.bas) is essentially the same
as the one we used last time, but I
have rewritten some of the comments
in an attempt to clarify them, so you
SERVO 05.2009
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