Break window

Open the Break window by issuing the BREAK command without providing any arguments. Close the window by issuing the BREAK command again without any arguments or by issuing the CLOSE command against that window. When the Break window is opened, it is positioned at the top right corner of the screen, overlaying any existing information. It uses only as many rows as needed to display the breakpoint information.

The window lists the active breakpoints and watchpoints. For watchpoints, the address is preceded by a "w" and the condition are displayed on the next line. Any commands associated with the breakpoint or watchpoint are shown on the following line. If there are more breakpoints or watchpoints than fit on the screen the NEXT and PREVIOUS commands scroll forwards and backwards through the list.

The Break window also lets you clear breakpoints. Breakpoints remain in effect until you explicitly clear them.

To clear a breakpoint, place the cursor on the field describing the breakpoint you want to clear, and either press the ERASE-EOF key or overtype the field with blanks.

Figure 1. An example of the Break window overlaying other windows

┌─01─Current Registers───┬05─Break Points───────────────────────────────────────┐
│  (TCAT) @PROLOG+44     │ w00057752 (TCAT) @DL00029                            │
│   R0 00009025  R1 0001 │   Condition:  = c r3,=f'3'                           │
│   R4 FEFE040F  R5 FEFE │  00057788 (TCAT) LOCRET                              │
├   R8 FEFE080F  R9 0005 └──────────────────────────────────────────────────────┤
│  R12 800576E0 R13 00012130 R14 000145CC R15 800576E0 FPR6 0000000000000000    │
├─02─Old Registers──────────────────────────────────────────────────────────────┤
│  (TCAT) @PROLOG+40                      PSW 078D10008005771E (CC mask= 4 L)   │
│  0005771E 9620 C0BA                  OI    CTGOPTN3,32                        │
│   R0 00009025  R1 000120D4  R2 FEFE020F  R3 FEFE030F FPR0 0000000000000000    │
│   R4 FEFE040F  R5 FEFE050F  R6 FEFE060F  R7 FEFE070F FPR2 0000000000000000    │
│   R8 FEFE080F  R9 000577BC R10 FEFE0A0F R11 FEFE0B0F FPR4 0000000000000000    │
│  R12 800576E0 R13 00012130 R14 000145CC R15 800576E0 FPR6 0000000000000000    │
├─03─Disassembly────────────────────────────────────────────────────────────────┤
│  (TCAT) @PROLOG+32                                                            │
│   00057716 92C1 C0CA                   MVI   CTGTYPE,193                      │
│   0005771A 943F C0BA                   NI    CTGOPTN3,63                      │
│   0005771E 9620 C0BA                   OI    CTGOPTN3,32                      │
│   00057722 4190 07D8                   LA    R9,2008                          │
│   00057726 5090 C108                   ST    R9,CATWRK                        │
│   0005772A 1F88                        SLR   R8,R8                            │
│   0005772C 5080 C10C                   ST    R8,CATWRKUS                      │
│   00057730 4190 C108                   LA    R9,CATWRK                        │
│   00057734 5090 C0C4                   ST    R9,CTGWKA                        │
│   00057738 4170 0002                   LA    R7,2                             │
├─04─Storage Dump───────────────────────────────────────────────────────────────┤
│  (TCAT) CTGOPTN3                                                              │
│   0005779A       21                                  .                        │
│  (TCAT) CTGOPTN4                                                              │
│   0005779B       00                                 .                         │
│  (TCAT) CTGENT                                                                │
│   0005779C 000577BC                              ....                         │
│  (TCAT) CTGCAT                                                                │
│   000577A0 00000000                              ....                         │
│  (TCAT) CTGWKA                                                                │
│   000577A4 00000000                              ....                         │
│  (TCAT) CTGDSORG                                                              │
└───────────────────────────────────────────────────────────────────────────────┘

 ==>

 1 Stmtstep   2 Regs       3 Quit        4 Until       5 Run         6 Dump
 7 Previous   8 Next       9 Disasm     10 Break      11 Step       12 Retrieve

z/VM: The Break window lets you enable or disable SVC trapping and PER operation. Change the SVC and PER settings by overtyping the values shown.