YOUR I-Dog !
Use a Picaxe microcontroller to
control your Sega I-Dog
I-Dog, Tamed, leashed and under
I got myself a Sega I-dog, the Japanese version, not the Hasbro
one that is sold in the US. You can get one from Ebay for about
$20. The Japanese version has a lot more features. It makes
a nice desktop companion with all the flashing lights, but can be very
annoying with tunes playing and gears moving.
So I wanted to tame that Doggie! You can carefully take it
apart and connect switches for the motor and speaker. I use a
Picaxe to activate the nose switch every few minutes to keep
it from sleeping. The Picaxe (M08) also uses a light sensor (CDS) to
detect darkness to allow the idog to go to sleep.
The board is connected to the proto board in the above photo with a
Picaxe Trainer board I invented. One of these days I will make it
available. You can connect a Picaxe and a few compenents on a
prefboard, if you perfer, to make the controller. At the bottom
of the page is a schematic and the Picaxe program.
Remove the battery
door and start removing the four screws that hold the body together
As you open the doggie, you will find a PC board with wires traveling
up the neck.
Masking tape placed inside by the factory, holds the wires down.
You can carefully remove the masking tape to get a better look
Take the face off to view the leds and nose switch. A single
motor is toward the lower right, just under the board.
After removing a screw that holds the neck down to the body, access to
the neck wires is possible.
The most important modification required is to attach wires parallel
with the nose switch.
If you look under the board, just below the spot were the nose
switch is, there are two gold testpoints.
I used a ohmmeter to locate two vias on the board to connect
wires. I used wire-wrap wire to make the connection.
Closeup showing were to solder the wires to activate the nose button.
Motor wires connect to M- and M+ pads. (see lower left)
Disconnect M- wire and connect to a piece of wire. Use heat
shrink tubing to cover joint.
Attach another wire to the M- pad.
By connecting the pair together outside the Idog, the motor is free to
Keeping it open keeps the motor off.
The Idog's speaker wires connect under the board to pads marked S+ and
Unsolder the S+ wire, connect to a piece of wire and connect another to
the S+ pad.
This pair will control the sound from the idog.
Attaching the power wires.
Upper right corner is +4.5 volts (red).
Just below the red wires is a orange wire. Connect +3 volts here
if you want power the motor.
Lower right, on the tiny PC board is the negative lead (common) of the
So there you go, That's the location of all the places were wires are
attached. The next phase is to bring them out to your Picaxe
I brought all the wires
to a pin strip and used ribbon cable with a connector to make the
connection to my Picaxe controller. Since I had no interest to
connect the motor, I just used the first 6 wires to connect to the
picaxe controller. Use of the motor will be done at a later date.
After connecting the nose switch to the optocoupler and you find it
does not turn on, reverse the connections to pins 4 and 5 of the
optocoupler. I used a 4N32 darlington opto, just because it was
all I had laying around. Any optocoupler should work. With an
ohmmeter connected to the nose switch, I found when pressed, it had a
resistance around 100 ohms. So because of that, in the beginning,
I inserted a 100
ohm resistor in series with the optocoupler. Found later it was not
required. The MCU uses a pull-up resistor.
Other uses for the controlled i-dog.
Add a RTC and make a alarm clock (activate the
Connect to the computer, write a program to use as a
alarm for instant messenger, email, etc.
Be sure to check my Flickr link for more detailed photos. If you
need a high res. photo, Email me.
Schematics of the Picaxe controller.
Controller.pdf Uses switches for sound and motor control.
turns on sound when waking up and going to sleep or if enough "nose
Controller3.pdf Minimum circuitry for a
controller with sound and lights. Use with idog2.bas
Program for the picaxe to control the
idog2.bas Activates the sound
Link showing very good dissection of the dog.
Another group took a Hasbro I-dog apart, good photos
My I-dog on Youtube, a demo, good varity of songs
Google Video, First tests after adding wires.
My Flickr photos of the autopsy
English translation of the manual from AudioCubes