micro. With this capability, you’ll be able to get to a new
level of understanding of how MakerPlot works and, also,
how you can create Interfaces that don’t involve first
loading a complete macro from the PC; the instructions
will come directly from your micro — or at least a portion
of them will in this example.
Figure 1 is where we’re going to begin. This is our
Arduino Uno with a 10K pot attached to the A0 analog
input. To display the pot’s value on MakerPlot, we’re
going to add two controls: a label called Pot Value and an
LED image holder consisting of 10 LED bars to our
(already customized) My_Interface.spm Interface. These
two controls will NOT be on the Interface screen to begin
with; rather, they will be added to it using code from the
Arduino.
The Approach
So, let’s discuss the best way
to begin to place controls on
MakerPlot directly from the
Arduino. By the way, it doesn’t
have to be an Arduino; you can
use most any of the popular micros
that have serial output capabilities.
The fundamental thing to realize is
that all controls on the Interface
have specific physical dimensions
and placement coordinates.
Figure 2 shows the
My_Interface.spm Interface with
and without the controls we’re
referring to. It’s in the marked
rectangular area on the left where
we’re going to add them (as shown
on the right). Once again, the goal
is to know what the dimensions
and placement coordinates are for these controls before
you send the MakerPlot instruction via the micro’s serial
port. Here’s how to do it.
The Technique
MakerPlot has an X, Y absolute coordinate system for
placing controls in the Object Area; this is the area of the
Interface that’s not occupied by the Plot Area. The
coordinates range from 0,0 at the bottom-left to 100,100
at the top-right. Use the Values Tab on the Toolbar to
locate these X,Y coordinates as in Figure 3.
We’ve moved our cursor to the rectangular area
where we want to place the controls that will come from
the micro’s serial port. We can then determine the exact
Figure 2. Before and after controls placement.
Figure 3. MakerPlot coordinate system.
July 2014 49
