Tuesday, January 22, 2008


Nowadays, it seems like real money (in the sense of cash) barely even exists anymore. We have debit cards, credit cards, paypal accounts, wire transfers... And in a sense, this is much more convenient than hiding 35 grams of gold under your pillow. On the other hand, as good as one may be at staring contests, it's a lot easier to convince a smart card that you put money on it than to convince 35 grams of gold that it's really 45 grams.

The laundry machines at my apartment building use SmartCity smart cards. There is a refill machine that takes debit (aka Interac) as well as credit cards. Here's what the cards look like (and the transcribed text for the benefit of search engines and visually impaired readers):


Smart cards by Coinamatic

Canada's Most Trusted Name in Apartment Services™"

"Please treat this card like cash. The value on this card will not be replaced if the card is lost, stolen, destroyed, or altered. Use of this card constitutes acceptance of the terms and condition stated in the SmartCity® Resident Card Information section on http://www.coinamatic.com/
Questions? 1-800-561-1972 ou customerservices@coinamatic.com"

On the back, in the bottom-left corner, is what looks like a 7-digit numeric serial number.

The electrical contacts you can see on the front side (first photo) are the typical ISO 7861 physical interface. Most (if not all) of these cards also obey the electrical interface and protocol defined by the same standard. Luckily for us, this means all we need to communicate with them is a clock generator, an RS-232 level shifter (MAX232) and a regular PC serial port.

Stay tuned for more details on what happened when I hooked the card up to my PC! For now, I've got some homework to do.


1 comment:

Anonymous said...

Excellent suspense-building tactics. Now I have no choice but to keep on reading ;)