to bump 3. 3 to five volts; we did this for smart
pixels and servos. If you’re using another board, you
can build this yourself; the circuit in Figure 5 has
appeared several times in my articles. I really like
the TC4427 and get a lot of use out of it.
Figure 6 shows the connections we used. The
HM- 10 is connected to male headers on the HC- 8+
using F/F jumpers from Pololu. I go through a lot of
these jumpers and I find that theirs are the best. For
these little radio projects, I replace the single-pin
shells on one end of the wires with a four-pin shell
that keeps the connections on the radio end in the
correct order. I leave the other ends as-is so I can
move things around on the HC- 8+.
You may be thinking that the HC- 8+ is overkill
for this — and I wouldn’t disagree if I were never
going to change anything. This is a demo piece for
trade shows and we often make updates on-the-fly.
Last Transworld (with our mini Stranger Things wall),
I was asked about controlling faux candles with our
products. The Propeller is perfect for that.
Since there were spare cogs, I wired the candles to
the HC- 8+, added a bit of code, and even a couple
commands so that they could be controlled from the
phone. John and I had been talking about the movie The
Karate Kid earlier that day, so I used the terms WAX ON
to light the candles, and WAX OFF to extinguish them.
Some Millennials didn’t understand the reference.
Honestly, I didn’t think the movie was that old.
The HC- 8+ has TLL inputs that one customer used to
spell pre-configured messages. It also has an RS-485 port
that can be used for DMX input or output. I put this to
use in Matt’s full-sized Stranger Things project. His show-control system would put command bytes on a specific
DMX channel that the HC- 8+ could detect and then use
to run a method that spelled specific words.
The timing matched the audio from the big show-control system; it was really quite cool. Yes, I’m biased
because I co-created it, but the HC- 8+ is a nice platform
for Propeller projects. If you’ve seen the Hollywood art
projects on my Pinterest page, you’ve seen a lot of
projects where I have put one or more HC- 8+s to work.
Again, you don’t need an HC- 8+ to create a project
like this, just a Propeller board and a few parts. The lamps
are about $40-$50, but you could re-purpose them for
other things. We used those lamps because John’s Ouija
board is oversized. If you went with a traditional size, you
could always use pixels cut directly from low-cost strips.
Just remember to change the pixel type in the setup()
function. Other than that, everything is the same.
Have fun, and Happy New Year! And, of course, keep
Spinning and winning with the Propeller! NV
January 2018 21
HC- 8+ Controller EFX-TEK #31208
HM- 10 BLE Module Amazon #B06WGZB2N4
F/F Jumper Wires Pololu #1700
1x4 Crimp Housing Pololu #1903
Brilliant Bulbs HolidayCoro.com
■ FIGURE 6. HC- 8+
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