viWhen the unit attention condition is set, the Target sends Check Condition status and then advances to item ix without executing the command.

viiThe Target rechecks the command operation code. If the command is Test Unit Ready, the command is executed. If there is a parameter error, however, the Target creates an error code and sense data and then advances to item ix. If the command operation code is not Send or Receive, the command is not supported by the scanner; the Target creates sense data and then advances to item ix.

viiiIf the Target receives the Identify message in item ii, it checks the Disconnect bit of the message, sends the Disconnect message if necessary, and changes to the Bus Free Phase. After completing preparations for data send and receive, the Target checks to determine if the Bus Free Phase is in effect, performs Arbitration and Reselection, reconnects to the Initiator, changes to the Message In Phase, and sends the Identify message.

The Target checks the operation code of the command received in item iv. If there is no error in the parameters, the Target executes the Send and Receive commands. If there is a parameter error, however, the Target creates an error code and sense data.

ixThe Target changes to the Status Phase and checks for error codes. If an error is present, the Target sends Check Condition status; if there is no error, the Target sends Good status.

xThe Target changes to the Message In Phase and sends the Command Complete message; it then changes to the Bus Free Phase to complete the series of communications.

A-14Interface Specifications