CP stores dl at X'1026', and d6 at X'1027'; when CP attempts to store c
at X'1028', it recognizes an incomplete hexadecimal character, and does
not store the last character.
General and control registers are loaded in fullword units. For
example,
store g4 123456
loads general register 4 with 00123456. store g4 12 34 56
loads general registers 4, 5, and 6 with 00000012, 00000034, and 00000056, respectively. Yoa can store data into one or multiple consecutive registers. Floating-point reqisters are loaded in doubleword units. Each
doubleword ooerand can be from 1 to 16 hexadecimal characters in length.
If less than 16 characters are specified, they are left justified in the doubleworj anit and padded to the right with zeros. For example:
store y2 00123456789 loads register 2 with the value 0012345678900000. Yoa can ase the STATUS operand of the STORE command to simulate the
hardware store status facility. Selected virtual machine data is stored
in permanently assigned areas in low storage. Your virtual machine must
be in extended control mode for the command:
store status
to be acceptea. To place your virtual machine in extended control mode,
issae the command:
set ecmode on
Be aware that this command resets your virtual machine and you must
reload (IPL) your operating system.
The data stored by the STORE STATUS command is summarized in the
following table:
virtaal Address No. of De:: • Hex. bytes Data
------- ------- ------ ------------
216 08 8 Processor Timer
224 EO 8 Clock Comparator
256 100 8 Current PSW 352 160 32 Floating-Point Registers (0, 2, 4, and 3814 180 64 General Registers (0- 15)
448 1CQ 64 Control Registers (0-15) If the operating system that is running in your virtual machine
operates in the basic control mode, these areas of low storage may be
ased for other purposes. You should not use this facility under these
conditions.
32 VM/370 CP Command Reference for General Users

VIRTUAL MACHINE ACTIVITY The TRACE command allows you to trace certain virtual machine activities
and record the results on either your terminal or the virtual printer,
or on both. You can trace anv one or more of the following virtual machine
activities: • SVC interruptions • 1/0 interruptions • interruptions • External interruptions • privileged instructions • instructions • Successful branches Whenever vou are recording trace output at your terminal, the virtual
machine stops execution and enters the CP console read environment after
each output line. This is the default mode of operation when, for
example, you enter:
trace all
-- or
trace svc program branch
If you only want to record the trace and not stop after each output
line, add the RUN operand as the last entry on the command line.
If, havinq specified multiple activities to be traced, you decide to
stop tracing one or more of them, enter:
trace program branch off
and tracinq is now confined to SVcs only.
To trace all activity with the output directed to the virtual
printer, enter: trace all printer When you stop tracing, you must also issue the CLOSE command to print
the spooled trace output on the real printer: ttace end
close printer
If your virtual machine configuration contains only one printer,
trace output is intermixed with application You should define
another virtual printer with an address lower than the previously
defined printer. Application output is still directed to the original
printer; however, trace output is always directed to the printer with
the lowest address. For a complete description of the TRACE command
alonq with the trace output formats, see discussion of the command in
section 5. While trace is running, portions of virtual machine assist are disableds When the trace is complete, they are enabled. For more
information, see the TRACE command discussion in section 5. Section 3. CP Command Usage 33