If your virtual machine is in extended control mode (ECMJDE), you can interrogate anv of the control reqisters:
display X1 4 A and receive the response:
EeR 1
ECR 4
ECR 10 xxxxxxxx
xxxxxxxx
xxxxxxxx However, the same command entered while your virtual machine is not
in exten1e1 control mode results in the response:
ECR 0 0 Ee: R 0 xxxxxxxx
xxxxxxxx
xxxxxxxx
As each operand in the command line is processed, VM/370 determines
that ECMODE is OFF and replaces any reference to a control register with
ECF 0, the onlv control reqister available in basic control (BC) mode.
PRINTER OUTPUT With the DUMP command you can dump the contents of all registers, the °SW and the storage keys, along with any specified area of virtual
storaqe, to the virtual machine's spooled printer. The printer format for storage locations is 8 fullvords per line plus the EBCDIC
+ranslation on the riqht.
To print only the registers, the PSW, and the storage keys, you need
only enter: dllmo 0 To also print an area of virtual storage, you can specify the
beginninq and ending hexadecimal locations: dLlmp 1064-10ff TOU can also specify the beginning location and the number of bytes
to be dumpe1; both values are entered in hexadecimal:
dump 1064.9b If you are printinq a series of dumps, you can
fncludinq its identification on the DUMP command
asterisk:
dump 1000-2000 * dump no. 1
identify each one by
line, following an
To oriat the dump data on the real printer you must first close the
virtual printer. Issue the command:
close printer and the dump 1ata spool file is placed on an appropriate system printer
queu e.
In addition, if vour installation has the VM/IPCS Extension program
product ilstallpd, you can use the VMDUMP command that dumps storage for
quest virtual machines. VMDUMP provides the VM/IPCS Extension with 30 IBM VM/370 CP Command Peference for General Users

header information to identify the owner of the dump; it also maintains
dump information, writes the dump to a spool file, and formats the dump. When you enter at the terminal vmdump i50-200 -- or --
vmdump 400:500 rp 1umps the contents of virtual machine storaqe at the hexadecimal
addresses between 150 and 200 or between 400 and 500, respectively.
If vou enter
vmdump 150.50 CP dumps the contents of virtual storage starting at hexadecimal address 150 for a total of X'50' bytes.
ALTERING VIRTUAL STORAGE You can the contents of your first level virtual storage, general
registers, floating-point reqisters, control registers (if available),
and the PSW with the STORE command. Virtual storaqe can be altered in either fullword or byte units. When usinq fullword units, the address of the first positions to be
stored must have either an L or no prefix: store 1024 46a2 or store 11024 46a2
results in 000046A2 beinq stored in locations 1024 store 1024 46 a2
on the other hand, implies storing 2 fullwords and results in the
storinq of 00000046000000A2 in locations 1024 throuqh 102B. If the starting location is not a multiple of a fullword, it is rounded down to the next lower fullword boundary. Each can be from one to eight hexadecimal characters in
length. If less than 8 characters are specified, they are right
;ustified in the fullword unit and padded to the left with zeros. You can store in byte units by prefixing the start address with an S. store s1026 d1d6c5
stores D1D6C5 in locations 1026, 1027, and 1028. Note that the data storage is byte aligned. If an odd number of hexadecimal characters is
soecified, co. does not store the last character, you receive an error
message, CP terminates the function. For example, if you specify:
store s1026 dld6c
Section 3. CP Command Usage 31