| 摘要 |
A system is disclosed for carrying out a chosen activity with a first unit with a memory, in occurring cases comprising a keyboard and a display, comprising a card for activating of the first unit, by correspondence between the card and the first unit, by adding from the card to the first unit a first code, which card comprises at least one programmable memory, for carrying out a chosen activity. The system is especially characterised in that the card (3,7) is provided to permanently store in the memory a first portion of said first code and is provided to be able, before the occasion of activation of the first unit, to be completed with a second portion to a complete first code, whereas the first unit or the card is arranged to erase said second portion of the first code from the memory of the card, after the performance of a chosen activity with the first unit. |
