Scenario1 - Defines a dataset on DASD (Direct Access Storage Device - SYSDA).

Code -

----+----1----+----2----+----3----+----4----+----5----+
//NEWPS  DD DSN=MTH.DATA.PSFILE,
//          DISP=(NEW,CATLG,DELETE),
//          UNIT=SYSDA,
//          SPACE=(TRK,(3,2),RLSE),
//          DCB=(DSORG=PS,RECFM=FB,LRECL=80,BLKSIZE=1600)

Scenario2 - Defines a new dataset on TAPE device (3490).

Code -

----+----1----+----2----+----3----+----4----+----5----+
//NEWPS  DD DSN=MTH.DATA.PSFILE,
//          DISP=(NEW,CATLG,DELETE),
//          UNIT=3490,
//          SPACE=(TRK,(3,2),RLSE),
//          DCB=(DSORG=PS,RECFM=FB,LRECL=80,BLKSIZE=1600)

Scenario3 - Defines a new dataset on two devices.

Code -

----+----1----+----2----+----3----+----4----+----5----+
//NEWPS  DD DSN=MTH.DATA.PSFILE,
//          DISP=(NEW,CATLG,DELETE),
//          UNIT=(,2),
//          SPACE=(TRK,(3,2),RLSE),
//          DCB=(DSORG=PS,RECFM=FB,LRECL=80,BLKSIZE=1600)

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