ASSGN IGN (ignore) specifies that any attempt to real from the specified
device results in an end-of-file indication; any attempt to
write to the device is ignored. IGN is not valid when
associated with SYSRDR, SYSIPT, SYSIN, or SYSCLB. UA indicates that the logical unit is to be unassigned. When you
release a disk for which an assignment is active, it is
automatically unassigned. LOWCASE 7TRACK q!RACK TRTCH a
DEN den translates all terminal input data to uppercase.
retains all terminal input data as keyed in.
is the tape setting.
refers to the tape recording technique for 1-track tapes. Use the following chart to determine the value of a. r--- -----, I a Parity converter Translator 1
1 I I 0 odd off off , I OC odd on off I I OT odd off on I I E even off off I 1 ET even off on 1 L--- -----J is tape density: den can be 200, 556, 800, 1600, or 6250
bits per inch (bpi). If 200 or 556 are specified, 7TRACK
is assumed. If 800, 1600, or 6250 are specified, 9TRACK is
assumed. (See Usage Note 8.)
1. When you enter the CMS/DOS environment with the command SET DOS ON, SYSLOG is assigned by default to TERMINAL. If you specify the mode
letter of the DOS/VS system residence on the SET DOS command
line, SYSRES is assigned to that disk mode.
2. You cannot assign any of the following DOS/VS system logical units
with the ASSGN command: SYSRES SYSUSF SYSLNK SYSREC SYSVIS 3. If you assign the logical unit SYSIN to a virtual device, SYSRDR and SYSIPT are also assigned to that device. If you make a logical
assignment for SYSOUT, both SYSLST and SYSPCH are assigned.
4. To obtain a list of current assignments, use the command.
5. To cancel all current assignments (that is, to unassign them), you
can enter, in succession, the commands:
set dos off
set dos on [mode]
6. If you want to access DOS/VS private libraries, you must assign the units SYSSLB (source statement library) , SYSRLB (relocatable library), and SYSCLB (core image library), and you
must issue the DLBL command to establish a file definition. 30 IBM VM/370 CMS Command and Macro Reference

ASSGN 7. An assignment to disk (mode) should be accompanied by a DLBL
command that provides the disk file identification. 8. If no tape options are specified on the command line, the default for a 7-track tape is 800 bpi, data converter off, translator off
and odd parity. If the tape is 9-track, the density defaults to
the density of the tape drive. 1600 bpi is the reset condition for
q-track dual-density tapes. If the tape drive is phase-encoded, density defaults to the density of the tape. If the tape drive is
NRZI, the reset condition is 800 bpi.
None. DMSASN003E INVALID OPTION 'option' RC=24 DMSASN027E INVALID DEVICE 'device' RC=24 DMSASN02AE NO LOGICAL UNIT SPECIFIED RC=24 DMSASN02QE INVALID PARAMETER 'parameter' IN THE OPTION 'option'
FIELD RC=24 DMSASN035E INVALID TAPE MODE RC=24 DMSASN050E PARAMETER MISSING AFTER SYSxxx RC=24 'option' OPTION SPECIFIED TWICE RC=24 DMSASN066E 'option' AND 'option' ARE CONFLICTING OPTIONS RC=24 DMSASN06QE DISK 'mode' NOT ACCESSED RC=36 DMSASN070E INVALID PARAMETER 'parameter' RC=24 DMSASNOA7E INVALID ASSIGNMENT of 'SYSxxx' TO DEVICE 'device' RC=24 DMSASNOqOE INVALID DEVICE CLASS 'deviceclass' FOR 'device' RC=36 DMSASNOq9E CMS/DOS ENVIRONMENT NOT ACTIVE RC=40 DMSASNl13S (cuu) , NOT ATTACHED RC=100 Section 2. CMS Commands 31