IBM 9348 Service Information page 257

This test verifies an erase operation from the current tape position to the end-of-
tape marker. The tape is rewound when the EOT is detected.
Parameter Description
A
0 Erase only
1 Write tape at group-coded recording (GCR) data rate first
2 Write tape at phase encoded (PE) data rate first
Diagnostic Test 101 (Write E lectronics Exerciser)
Parameter A = density. A scratch tape is needed for this test.
This exerciser writes an all ones pattern in the specified density from the present
tape position to the end-of-tape marker. The tape is rewound when the EOT is
detected.
Diagnostic Test 102 (Read E lectronics Exerciser)
Parameter A = density. A scratch tape is needed for this test.
This exerciser runs from the present tape position to the end-of-tape marker with the
read electronics turned on and setup in the specified density. The tape is rewound
when the EOT is detected.
Diagnostic Test 103 (Read Reverse Exerciser)
Parameter A
=
density. A scratch tape is needed for this test.
This exerciser positions the tape at EOT and then runs in the reverse direction to the
beginning-of-tape marker with the read electronics turned on and the density
selected.
Diagnostic Test 104 (Head Crosstalk Exerciser)
Parameter A
=
density. A scratch tape is needed for this test.
This exerciser rewinds the tape, then runs to the EOT marker with the erase head on
in order to prepare the tape for crosstalk. It then runs in the reverse direction to the
beginning-of-tape marker with the read and write circuits operating and the density
selected.
Diagnostic Test 108 (Current Gain Profile Display)
Parameter
A = display select 0, 1, or 2.
This test displays the gain profile for the tape now loaded. The gain profile is read
whenever a tape is identified (following a LOAD or a REWIND) or a density identifi-
cation is written.
Display Select 0 displays the load gain profile for the last tape loaded. Display
Select 1 displays the load gain profile for the tape now loaded relative to the stored
profile. Display Select 2 displays the present profile used for reading and writing
the tape. It is the stored profile normalized to match the average gain of the tape
now loaded. Gains are displayed as described in Test 98. For PE tapes, Display
select
u
ana
I
WIII
snow t r a m
4
only (the ~t
IU
track).
Appendix B. nagnostic Tests
8-1 5