■ FIGURE 18
■ FIGURE 16
■ FIGURE 17
Carrier 1 board, as well. The board sits
higher than the FireCracker so you will
need two to three layers of the foam
tape for the added height. Attach the
four-cell battery holder next. You may
also want to use some tape to hold the
sensor pad wires in place. Make sure
you don’t use metal tape for this.
Load up program DDishP3.txt and
program it into the DiosPro. This
program takes advantage of a few of
the hardware features built into the
DiosPro. The DiosPro has the
ability to be put to sleep and
will draw only about 40 µS of power
from the battery in this mode. To wake
up the DiosPro, we use another
feature called the watchdog timer.
When turned on, it will wake up the
DiosPro after it has been asleep for
two seconds. If you look at the code,
you will see that I make 130 calls to
the sleep command. This causes the
DiosPro to stay on a low power mode
for five minutes. Once it wakes up, it
does a dish test then turns the X10
device on or off depending on
the reading. We are providing
the power to the FireCracker, so
just before we put the chip to
sleep the power is removed so
that the FireCracker itself does
not drain the battery.
Another hardware feature of
the DiosPro is the ability to
self-monitor the supply battery.
We make a call to this routine
once each cycle and if the
battery voltage drops below 4. 24
volts, it will toggle the device five
times to warn us.
LINKS TO PARTS
AVAILABLE FROM KRONOS ROBOTICS com/xcart/customer/ product.php?
AT www.kronosrobotics.com: productid=16288
■ DiosPro28 — www.kronosrobotics.
AVAILABLE FROM www.X10.Com:
■ Dios Carrier 1 — www.kronosroboti
■ FireCracker — (Note the FireCracker
can be purchased cheaper from an eBay
AVAILABLE FROM ALL ELECTRONICS
■ EZRS232 Driver — www.kronosrob
■ Strobe Light — www.allelectronics.
■ Four-cell Battery Holder — www.
AVAILABLE FROM HOME CENTER:
■ Foil Tape — Standard HVAC metal tape.
■ 36-pin Female Header — www.
■ Double Stick Foam Tape — Used to
secure the Dios Carrier 1 and FireCracker
to the inside of the bowl.
■ Nine-pin DSub Plug — www.kronos
■ Hookup Wire — I used wire removed
from standard telephone cable (Cat 3).
■ 100K Resistors — www.kronosrobot
AVAILABLE FROM PET STORE:
I have been using the dish now for
a couple of months and it has worked
without a failure. The alkaline batteries
I have been using also show no signs
of significant drain.
The complete schematic for the
final assembly is shown in Schematic
2. Feel free to make modifications.
There are several ports available for
connecting things like LEDs, beepers,
or other devices. You could also run a
couple of additional sensor pads to
test different water levels. For instance,
use port 14 to run a second toggle
pad. Just make an additional call to the
Dish Test routine passing I/O port 14.
As for the water level warning
indicator, just about any lamp will
work. I use something a little different.
I use one of those strobe flashers connected to an AC adapter as shown in
Figure 18. I’m using the standard lamp
module that came with the CM18
FireCracker kit. The strobe will flash
whenever the dish needs more water.
The FireCracker — also known as
the CM17A — is not an X10 device, nor
does it communicate with the X10
protocol. It is a wireless transmitter that
is designed to work with the TM751
transceiver module. While you can
purchase the CM17A by itself, it won’t
do you any good unless you already
have a TM751. This is why they created the CM18 FireCracker Kit. This kit
contains the following modules:
■ Heat Shrink — www.kronosrobotics.
■ Water Dish — I purchased the bowl I
used from PetSmart. I have seen them
at various department stores, as well.
• FireCracker Module (CM17A)