IBM B-Series, Maintenance Information

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Power Sequencing:
When power is applied, internal logic of the integrated control unit checks the
voltages. When all the voltages have tested correctly, the power-on self-test (POST) is executed at
power-on time by the RAS microcode. If the voltage is out-of-spec, the subsystem logic is held in the reset
state. Errors detected during the power-on sequence are displayed in the LED indicators on the drive and
on the Library operator panel if installed.
Subsystem Diagnostics
Subsystem Diagnostics are divided into two categories:
Power-on self-test (POST)
Functional Tests
POST Diagnostics:
POST diagnostics are initiated at power-on time. They are a combination of
built-in self-tests of logic modules, memory tests, control logic, sensor tests and data path tests. A portion
of the POST diagnostics is also executed when a fix-verification test is invoked from the host processor
via a SCSI command.
Errors detected during execution of POST are displayed as a FRU identifier code (FID) in the drive LED
indicators and on the operator message panel of Library models. The error information is also sent in a
service information message (SIM) over the SCSI interface if the customer application supports the SIM
feature. The FID can be cross referenced to the entry table in Figure 8 on page START-12.
Functional Tests:
The functional-test diagnostics verify that the machine performs without errors.
They can be invoked at any time either to verify a fix or to exercise the subsystem. These diagnostics may
be invoked from the host via a SCSI command or from the drive operator controls or the operator panel on
the library. See “Verify Fix” on page PROC-9 for detailed descriptions of test selections.
Special RAS Characteristics:
The special RAS characteristics include:
Real-time diagnostics
Real-time failure isolation
Hardware/media isolation
Online microcode update
Also, the subsystem design permits:
Complete self-testing whenever the subsystem is powered on.
Operator notification whenever a failure is detected.
Special Tools:
Special tools are either shipped, purchased, or ordered to repair the subsystem. See
“Cleaning Cartridge” and Figure 50 on page INTRO-49 for examples of special tools.
Cleaning Cartridge:
A special cleaning cartridge is part of the 3570 subsystem. This tool (P/N
05H2463) is used to clean the tape head. It is shipped with the subsystem. The cleaning cartridge is
identified by a gray file protect selector. The need for cleaning is determined by the microcode in the 3570
Tape Subsystem.
Model B00 Drive: If the operator does not have ready visibility of host console messages when cleaning
is required, the Clean LED indicator (see Figure 46 on page INTRO-41) will also flash to indicate that
cleaning is required. The operator will load the cleaning cartridge on the drive and the cleaning procedure
occurs automatically. The cartridge unloads when the cleaning procedure is done.
INTRO
Introduction
INTRO-47