摘要 |
PROBLEM TO BE SOLVED: To compose a data carrier system effectively usable when a lot of slave machines are present in a search area and when it is used in an environment having a small number of slave machines in the search area. SOLUTION: By composing this data carrier system effectively usable when a lot of slave machines are present in the search area and when it is used in the environment having a small number of slave machines in the search area by forming an ID holding means for holding plural IDs for responding to calls a reader/writer device, advantages in the case of a large number of ID bits for a slave machine and in the case of a small number of the ID bits therefor can be provided according to a time, place and occasion. |