DATA COMMUNICATION APPARATUS

摘要

Data communication apparatus comprises a master unit (2) and at least one physically separate, passive slave unit (4). The master unit (2) has a first part (29) of an inductive communication system, and a processor (20) connected to the first part of the inductive communication system. The slave unit has a second part (40) of the inductive communication system, a data store (48), and a modulator (44, 49) responsive to data from the data store and connected to the second part (40) of the inductive communication system. The first and second parts of the inductive communication system (29, 40) are constructed so that when the slave unit (4) is brought into proximity with the master unit (2), power is inductively coupled from the master unit to the slave unit via the inductive communication system. The modulator (44, 49) in the slave unit (4) is thereby activated to cause data from the store (48) to be inductively communicated from the slave unit (4) to the master unit (2) via the inductive communication system. The processor (20) is responsive to the data supplied to the master unit (2).