the functions you want to incorporate.
There will be problems when you try to duplicate
anyone’s complicated LabVIEW VI. Even having an
electronic copy of a VI does not guarantee that it will
operate on another MyRIO or PC without some
troubleshooting taking place.
There are many files associated with any VI, and
they can be located in different folders, directories, etc.,
on different computers. I realize that this system is not a
cost-effective replacement for a $20 household
thermostat. This is just a way of providing a universally
understood control system, and using LabVIEW and the
MyRIO to solve the task while learning how to use them.
The file view, front panel, and block diagram for
this VI can be seen in Figures 4, 5, and 6. Figure 6 is an
overall view of the complete diagram which will be broken
down into individual boxes in the sections that follow.
When explaining how the VI operates, most of the time
will be spent going over how the block diagram works. It
should be fairly straightforward to recreate the front panel
and place the same controls and indicators as well as the
iPad data dashboard. To make the block diagram
explanations easier to follow, decorative frames were
placed around most of the areas. Numbers were placed in
the upper left corner of each decorative frame. These
frames are for documentation purposes only and do not
affect how the VI operates.
The Initialize frame on the left simply makes sure that
the heat and cool outputs to the MyRIO D I/O lines are
off. It also initializes who
sets control to the front
panel; this might be
necessary in the event
someone using an iPad
had set itself as the
temperature controller
and did not return this
control back over to the
front panel. The Close
frame on the right makes
sure that the heat and
cool MyRIO outputs are
off. The explanations will
be listed in order frame
by frame. However, we’ll
call it box by box here so
as not to be confused
with the sequential
frames.
First, a word about
the wireless “network
published” variables you
will find located
throughout the block
diagram. They are only
necessary if you want to
include the wireless control and display features through
an iPad data dashboard. For example, in box #5 is the
green MODE_CON rectangle with an arrow pointing out
of its right side. There is a corresponding MODE_CON on
the project view window under the DDASH_TEMP.lvlib
label. This icon was placed in box #5 by dragging it from
the project view window down onto the block diagram.
The arrow on its right side is pointing out; this means
that it is in the READ mode and will be wirelessly
receiving data from the iPad data dashboard control linked
to MODE_CON. It will receive this data from the iPad
control and pass that data into the VI. The green color
signifies that it is a BOOLEAN type of data — either a T or
F. Notice on the block diagram in box #10 there are two
orange boxes with the words “temp” and “set” in them.
FIGURE 5.
FIGURE 6.
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