Two way communication token interrogation apparatus

A coin operated machine comprising a coin validator and a token reading device for communicating with a data-storing token, said token reading device comprising:

• inductive coupling means for inductively coupling said reading device with said token, the inductive coupling means comprising transmitting antenna means for transmitting a signal to a token, said signal directly supplying power to said token;
• signal generating means for generating and applying said signal to said antenna means, said signal generating means comprising means for modulating said signal in dependence on data to be transmitted to said token;
• and
• data detection means coupled to said inductive coupling means for detecting changes in the transmitted signal caused by alterations of the impedance of said token, thereby to detect data transmitted by the token,
• said coin operated machine being capable of performing operations in dependence on an output of the coin validator.

A token for use with a token reading device for communicating with a data-storing token, said device comprising:

• inductive coupling means for inductively coupling said reading device with said token, the inductive coupling means comprising transmitting antenna means for transmitting a signal to a token, said signal directly supplying power to said token;
• signal generating means for generating and applying said signal to said antenna means, said signal generating means comprising means for modulating said signal in dependence on data to be transmitted to said token;
• and
• data detection means coupled to said inductive coupling means for detecting changes in the transmitted signal caused by alterations of the impedance of said token, thereby to detect data transmitted by the token, the token comprising (a) inductive coupling means for receiving the signal transmitted by the inductive coupling means of said token reading device. (b) power supply means for supplying the token with power derived from the signal received by the inductive coupling means of said token, (c) data detection means for detecting modulations of said signal and deriving data therefrom, (d) data transmission means for selectively altering the impedance of said inductive coupling means of said token in dependence upon data to be transmitted to said token reading device so as to cause changes in the signal transmitted by the inductive coupling means of the token reading device, (e) a non-volatile writable memory, and (f) control means for deriving from said memory data for transmission by said data transmissions means of said token for writing into said memory data determined by the data detected by said data detection means of said token.