IBM System/370 Operator's Reference Manual page 43

System/370 Model 115 and Model 125 (cont'd)
To Display Registers, PSW, and Main Storage
1.
Select ALTER/DISPLAY by keying A in the MODE SELECTION display and
pressing ENTE
R.
'MODE SELECTION'
SYSTEM RESET
ADDRESS COMPARE
PROGRAM LOAD
INTERVAL TIMER
CHECK CONTROL
STORAGE DUMP
ICA LINE MODES
A AL TER/DISPLAY
I INSTRUCTION STEP
P RESTART
M MAINTENANCE
S STORE STATUS
U SAVE USAGE COUNTERS
MODE SPECIFICATION**-'*
2. Select the desired display from those listed on the ALTER/DISPLAY frame.
'ALTER/DISPLAY'
G GENERAL REGISTERS
C CONTROL REGISTERS
CURRENT PSW
FLOATING POINT REGS
K PROTECTION KEY
M MAIN STORAGE KEY
STOR/\GE ADDRESS
OOOOOO-FFFFFF
OOOOOO-FFFFFF
V MAIN STORAGE VIRTUAL OOOOOO-FFFFFF
ADDRESS:
3. Key in the selector character: G for General·Purpose Register, P for Current
PSW, etc. With Main Storage and Protection Key you must also key in the
address.
4. Press ENTER.
To Alter Registers, PSW, and Main Storage
1. To change one or more of the digits in the display, move the cursor under
the first digit to be changed.
2. Key in the new data. The new data" appears on the line under thp old data
3.
Before ENTE R is pressed you can still change your input by using the cursor
keys and entering the changes in the usual way.
4.
Press ENTER. The new data replaces the old on the screen.
NOTE: If INVALID CHARACTER appears on the screen, you entered a
wrong character (either a nonhexadecimal or a nonbinaryl. The
cursor marks the first invalid character. Key in the correct informa-
tion and press ENTER.
Procedure after an Alter/Display
1. Press MODE SEL to get the ALTER/DISPLAY frame again; or
2.
Press MODE SEL twice to get the MODE SELECTION frame; or
3. Press CNCL key to return the screen to the operating system and the
START key to resume processing.
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