System Debug Reference Manual (32650-90888)

Chapter 8 309
System Debug Windows
8 System Debug Windows
System Debug offers a powerful and efficient set of screen-oriented "windows," which allow
dynamic visual monitoring of the program environment.
The System Debug windows are initially disabled, but can be easily toggled on (WON) and
off (WOFF). Users can continue to use all normal interactive commands while the windows
are displayed.
The following windows are provided by System Debug:
• The
register window (R) displays the current CM register values
• The
general register window (GR) displays the current NM general register
values.
• The
special register window (SR) displays the current values of a collection of
special NM registers (including the space registers).
• The
program window (P) tracks the program counter in the current mode (NM or
CM). Current executing instructions are displayed and breakpoints are flagged. For
convenience, the program window for one mode can also be accessed from the other
mode with the fully qualified name (CMP or NMP).
• The
frame window (Q) highlights the most recent CM stack marker. By default, this
window displays addresses as unsigned DB-relative values. The user may choose to
have addresses displayed relative to DB, Q, S, DL, or the DST base. Addresses may be
displayed as signed or unsigned values. For details on these options, see the QM
command. This window may also be aimed at any valid DST to which the user has
access.
• The
stack window (S) tracks the current CM top of stack. By default, this window
displays addresses as unsigned DB relative values. The user may choose to have
addresses displayed relative to DB, Q, S, DL the DST base. Addresses may be displayed
as signed or unsigned values. For details on these options, see the SM command. This
window may also be aimed at any valid DST to which the user has access.
•A
group window (G) is a special window within which the user can custom-define
individual user windows (UW). These user windows (subwindows) can be "aimed" at
parameters, variables, data blocks, and so on. Up to three group windows can be
defined.
•A
virtual window (V) displays data at a native mode virtual address. Up to eight
virtual windows are available.
• The
memory window (Z) displays data at a native mode real address.
• The
ldev window (L) displays the contents of secondary storage at the specified disk
address expressed as a logical device (LDEV) and byte offset.
•A
text window (TX) displays information in a text file. Up to three text windows are
available.