BYPASS=YES ftODEL=n is that the program's defective track checking feature is to
be bypassed. If BYPASS is omitted, the program assigns an
alternate only if it finds that the specified track is
defective.
is a decimal model number (lor 2). This operand is only for
the 2305 and corresponds to the 2305-1 and 2305-2, respectively. !gte: A list of defective tracks (if any) is provided with new IBft disk
storage volumes. Refer to this list when using the IBCDASDI prograa for
the first time. After initialization, include the GETILT statement in an IBCDASDI job to assign an alternate track for each track on the list.
Subsequent IBCDASDI jobs "remember" those defective tracks, unless the PLAGTEST=NO option is specified for those jobs.
The example below shows the control statements that might be prepared to
initialize a dedicated 3340 disk that is to be initialized by running IBCDASDI in a virtual machine. The disk is to be labeled VftRES and it
is mounted on unit address 240. INIT240 JOB ftSG DADEP VLD YTOCD END TODEV=1052,TOADDB=009 TODEV=3340,TOADDB=240,VOLID=SCRATCa, FLAGTEST=NO,BYPISS=NO NEiYOLID=YftBES STRTADR=1,EXTENT=1 C Since the PASSES operand was not specified, it defaults to PISSES=l and
a non-Quick DASDI function is perforaed. All tracks, including any that
were previously flagged as defective, are tested. Plagged tracks that
test okay are recovered (not flagged). lny tracks that do not pass the
test are flagged and an alternate track is assigned.
The example below shows the control statements that aight be used to
explicitly assign alternate tracks to two tracks on the same disk shown
in Example 1. It is assumed that these two tracks were found to be
defective when the disk vas put into use, subsequent to its
initialization in Exaaple 1. Once again the disk aust be dedicated to
the virtual machine in which IBCD1SDI will be run. MOREALTS JOB ftSG GETALT GETILT TODEV=1052,TOADDR=009 BYPISS=YES,TRICK=00FB0003 TODEV=3340,TOADDR=240,VOLID=VftRES, BYP1SS=YES,TRICK=011C0005 c
The TRACK operands specify the hexadeciaal ccaa addresses of the tvo
tracks that get flagged as defective. Section 4. Yft/310 Service prograas 191

1 The example below shows the control statements that might be prepared to
initialize the 2314 minidisk LIBRES for OS data set residence. Note
that the label of the real volume, CPVOL1, cannot be used as the VOLID operand.
JOB MSG DIDEF VLD VTOCD END TODEY=i403,TOADDB=OOE TODEV=2314,TOIDDR=231,VOLID=SCRITCB,CILNO=50 NEWVOLID=LIBRES,OWNERID=OPERITIONS STRT1DR=10,EXTENT=5 The desired size of the minidisk is specified through the CILlO operand. The value specified includes one cylinder reserved for
alternate track assignment; a user assigned n cylinders has n-1 of these
initialized for his use; and the nth cylinder used for any alternate
track assignment. The minimum size of a ainidisk can be coaputed froll the formula below. In it, N represents the minimum number of cylinders,
and K represents the number of recording heads of the device. The SIZE-OP-VTOC value should be in tracks, and the result of the division
should be rounded to the next highest integer.
N = 2 + (SIZE-OP-VTOC / K) Por 2305 ftodels 1 and 2, 3330, 3340, and
cylinders of a minidisk are assigned for your use.
for alternate track assignment. IIVOKING THE IBCDISDI PROGRAM 3350 devices, all n No allowance is made The IBCDISDI prograa is invoked for minidisks by specifying the operand ••• ,CYLIO=nnn on the DIDEP control statement (discussed previously). This control
statement is passed to the IBCDISDI utility for processing. This
operand ·specifies the size, in cylinders, of the minidisk to be initiated.
The IBCDISDI program, which is distributed as a CftS file with a
filename of IPL and a filetype of IBCDISDI, should be spooled to your own virtual card reader. Control statements for the program can follow
the last card or card image for the program, or can be entered via a
separate input device.
To execute the IBCDASDI program:
1. Make sure ECftODE is off for your virtual machine; use the QUERY command to determine this. Use the command to modify if
required. Spool a copy of the IBCD!SDI object .odule to your virtual card reader, or mount and attach the tape containing the object program. 3. Load the object program from the virtual reader or tape by issuing
the CP IPL command for the appropriate virtual device address. When the program is loaded, an enabled wait state is entered with
the address field of the PSi containing the hexadecimal value FFFF.
192 Vft/370 Operator's Guide