Assembled shield on a RedBoard/Arduino
Prototyping Area
Let’s address the elephant in the room. There’s almost half a shield that
we’ve failed to talk about thus far: the prototyping area! These rows and
columns of 0.1"-spaced plated through-holes can be used to solder in all
sorts of fun components.
Near the proto area is a set of six pins. With the isolation jumpers opened
underneath, these allow you to interface directly to the inputs of the L298.
The six pins of the ISP connector are outlined within the proto area. These
are just plated through holes, and are labeled to warn you that the pins
underneath come up really close. If you absolutely need these, you may
end up removing the ISP header from the attached Arduino.
Here are some ideas of what to do with it:
• Leave it alone! — If you’re happy with just driving motors, you’re
good to go.
• Add an accelerometer to enable bump detection in your robot.
• Fill it with LEDs to make your project as blinky as possible.
• Add current sense resistors, an op-amp, and measure the current of
the motors being driven.
• Disconnect all the jumpers and wire up the L298 in any way you
please.
Unlike other prototyping areas you may have encountered in the past,
these holes are
not wired together
. You don’t need to do any trace-slicing,
but you will need to do some soldering and wire routing.
Motor and Wheel Assembly
This is where the shield assembly gets very project-specific. Have you
picked out which motors you’ll be driving with the shield? Do you know how
long the wires need to be trimmed? There’s a lot to be answered here
before continuing on…
Motor Wiring
If you have the kit, the motors come with wires attached, but take the time
to notice how they are wired. They are a left-right pair, which can be seen
by holding the motors in the same orientation and looking at how the red
and black wires are attached. When they are installed with the wire-side
facing each other, a positive polarity drives either motor “forward,” even
though one is spinning clockwise while the other spins counterclockwise.
Connecting Motors
If you added screw terminals in the last step, break out your screwdriver,
slide the wires in, and tighten the terminals down.
In lieu of screw terminals, you can solder the motor wires into either the 0.1"
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