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ACL 4/52 Software Interface Guide
Document 6211225-03
Version 3.0
2-16
System Diagnostic Support
System Diagnostic Support
The library unit has a layered self diagnostic capability. Each layer
addresses a specific type of diagnostic need. The layers provide a basic
go/no-go capability as-well-as complete fault isolation capability.
Host Interface Diagnostic Error Codes
This lowest layer consists of the tests that are performed when the
library unit is placed on-line. These tests are designed to catch all
major system failures and give the host computer a high degree of
confidence that the library is operational. This layer has been kept as
simple as possible to minimize the amount of support software
required at the host.
The next layer allows isolation of faults that occur during operation.
Error definitions and recovery procedures, provided in Appendix A,
are designed to be descriptive enough to quickly test failed operations
and correct any conditions that would have resulted in an unnecessary
service call.
Off-line Diagnostics via the “DIAG” Port
The top level of diagnostic commands are available through the use of
the Diagnostic Software Program (DSP) interfacing to the library over
the “DIAG” Port on the rear of the library. The commands are
designed for use by an authorized Field Service Engineer and are
intended for use with the fault isolation procedures described in
Document 6211223, ACL 4/52 Field Service Manual. Use of the DSP is
described in Document 6211224, ACL 4/52 Diagnostic Software User’s
Manual.