← Back to Patent Explorer
JPH04321191A Expired / Lapsed JP ⏱️ 0.0 years remaining

Portable electronic device

Assignee: Toshiba Corp
•
Filing: 1991-04-22
•
Granted: —
•
Expires: 2011-04-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract PURPOSE:To always attain the accurate communication of data even to an external device containing different data communication protocols by selecting a communication protocol corresponding to the external device out of those communication protocols with designation of the external device. CONSTITUTION:A mask ROM 2 of an IC card 1 contains two types of communication protocols A and B. Then the communication of data is carried out to an external device (reader/writer), a CPU 4 outputs the initial data showing that the 1st and 2nd priorities are given to the protocols A and B respectively to the external device. Then a command waiting state is set by the protocol A. If the data received from the external device commands the selection of a communication protocol and designates the protocol B, a command waiting state is set by the protocol B.

Inventors

  • 👤 Yasuo Iijima
  • 👤 康雄 飯島

Bibliographic Details

Application Number —
Jurisdiction JP
Data Source google_patents
Last Synchronized 2026-11-02 07:24
CPC Classifications
—

Claims Analysis

Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag