Learning About Skannerz Racerz

A recent birthday arrival in the house was a Skannerz Racerz toy. The first arrival was mysteriously followed soon after by a second one :-), seemingly by coincidence in August 2007 they were discounted at the red shed for $NZ9.97 down from $NZ19.56. (In early September 2007 I discovered over-priced Skannerz Racerz online here for $NZ49.99!)

I've been interested in learning a bit about how they work. Much to my surprise the internet let me down and there seemed to be no useful information to be found from searching "skannerz racerz" hack. As a result I thought I'd document what I found.

The benefit of having a second Racerz toy is two-fold:

• The toys are designed to be linked together (via three small metal pins at the top of the units) to enable two-player head-to-head racing—a second unit enables this to happen.

• No tears from an under-eight year-old should any research prove fatal to the device under investigation. :-)

External views

Here is the view of the front of the device, displaying the menu as it appears when the device is first turned on:

Below is the rear of the unit with the battery cover in place:

The battery cover is imprinted with:

RADICA:(R)
(C)2004 RADICA GAMES LTD.
PRODUCT SHAPE(TM)
ALL RIGHTS RESERVED
RATING: DC 4.5V === 0.3W
BATTERY: AAA(LR03) X 3

MADE IN CHINA

Disassembly

. Step 1 .

Remove the single Phillips-head screw (A) holding the battery cover in place:

. Step 2 .

Remove the battery cover to reveal the battery compartment with space to hold 3 AAA batteries:

Here is the view of the inside of the battery cover:

Nothing too exciting to be seen here—I'll leave you to see what mysteries are behind the two small Phillips-head screws holding the "tabs" in place.

. Step 3 .

Remove the six (6) Phillips-head screws (A)(B)(C)(D)(E)(F) that hold the two halves of the device shell together:

. Step 4 .

Before you start to split the two halves of the case ensure the small red transparent filter at the bottom of the barcode scanner handle doesn't fall out and get damaged when you open the shell:

@@ TODO: Add photo of red filter and location here?

. Step 5 .

To split the two halves of the case apart you may need to insert a small flat blade screwdriver or similar object into the seam between the two halves and sliding it gently along the seam.

@@ TODO: Add photo?

I would suggest leaving the device face-down when opening it.

. Step 6 .

Carefully lift the battery compartment half of the case off the screen and button half of the case, twisting slightly anti-clockwise (at least in my unit) to untwist the cables inside. The "wheel" controller, the speaker and the barcode reader electronics will stay attached to the battery compartment half of the case. Note the cable attached to the wheel controller is not long enough to lay the two halves side-by-side unless the wheel controller is unscrewed from the case (untested):

@@ TODO: Add photo.

. Step X .

You will need to unscrew the screw (X) holding the black electrical tape in place.

@@ TODO: Add photo.

@@ TODO: To be continued

---

Notes so far

• Internals seem to consist of a main PCB (connected to screen) with a separate smaller PCB dedicated to the barcode scanner.

• Only one site seems to detail any technical information related to the hardware of any of the Skannerz series of toys. The site features a brief description with small schematic.

• The main PCB has some helpful silkscreen markings. (From memory this includes the detail that the centre pin of the three "link" pins is ground.)

• A magnet is contained beneath the round recess at the top of the unit—this attracts the metal stud protruding from the top of the matching unit when two devices are linked.

• The barcode PCB features a LM358 - Low Power Dual Operational Amplifier from National Semiconductor. (The National site has a section on understanding the special code marks on the IC package surface to determine date of production etc.)

• The units can be linked successfully with ~2 metre lengths of cable between them.

• GND <-->Vcc = ~4.65V

• LCD connected to PCB via "ZEBRA Elastomeric Connectors" on two edges. "Elastomer Connector A strip of silicone rubber made up of sequentially spaced conductive and non-conductive material." -- http://www.anglia-displays.com/glossary.asp a.k.a. Zebra strip

• Possible 2KHz Skannerz Racerz link clock signal:

• Possible Skannerz Racerz link "ping" signal:

   xoscope -1 0 -m 1 -v