最終更新:2015-02-25 (水) 15:44:38 (2035d)  

ACK
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USB/ハンドシェイクパケット

  • 正常受信

概要

  • ACK indicates that the data packet was received without bit stuff or CRC errors over the data field and that the data PID was received correctly.
  • ACK may be issued either when sequence bits match and the receiver can accept data or when sequence bits mismatch and the sender and receiver must resynchronize to each other (refer to Section 8.6 for details).
  • An ACK handshake is applicable only in transactions in which data has been transmitted and where a handshake is expected.
  • ACK can be returned by the host for IN transactions and by a function for OUT, SETUP, or PING transactions.