Sense Codes for SDI Messages

When the local node detects an error in a normal flow request from the host, the message is converted into a DATAFMI message with the system detected error indicator (SDI) set to inform the application and to allow data to be processed serially. The application must convert the message to a Status-Acknowledge(Ack) to allow the local node to send the required negative response to the host. The possible error codes delivered to the FMI application on such SDI messages are tabulated below.

The sense codes beginning with 0x40 will only be delivered if the corresponding receive check has been enabled in the CICB on the Open(SSCP) Request from the application. If a receive check has been disabled, the message can still be converted to an SDI message; for example, a message with BB, -BC would fail as 2002 or 2003 if 4003 were disabled.

When the application uses a Status-Control(LUSTAT) Request to reject outbound data (see LUSTATs), the sense codes supplied by the application will be present on the SDI message generated by the local node.