Specifications

Debugging a Device Driver
11.2 Using the OpenVMS AXP System-Code Debugger
Boot Command Example The following command boots a DEC 3000 Model 400
from the dka0 disk, enables the system-code debugger, defaults to using XDELTA,
and takes the initial system boot breakpoints:
>>> boot dka0,esa0 -fl 0,8006
You can set these devices and flags to be the default values so that you will not
have to specify them each time you boot the system. On a DEC 3000 Model 400,
use the following commands:
>>> set BOOTDEF_DEV dka0,esa0
>>> set BOOT_OSFLAGS 0,8006
System-Code Debugger Configuration File
The system-code debugger target system reads a configuration file in
SYS$SYSTEM named DBGTK$CONFIG.SYS. The first line of this file contains
a default password, which must be specified by the host debug system to connect
to the target. Other lines in this file are reserved by Digital. Note that you must
create this file because Digital does not supply it. If this file does not exist, you
cannot run the system-code debugger.
XDELTA Commands
When the system is booted with the 8000 boot flag, the following two additional
XDELTA commands are enabled:
• n,\xxxx;R Control System-Code Debugger connection
This command can be used to do the following:
Change the password which the system-code debugger must present
Disconnect the current session from the system-code debugger
Give control to the remote debugger by simulating a call to INI$BRK
Any combination of these
Optional string argument xxxx specifies the password that the system-code
debugger must present for its connection to be accepted. If this argument is
left out, the required password is unchanged. The initial password is taken
from the first line of the SYS$SYSTEM::DBGTK$CONFIG.SYS file .
The optional integer argument n controls the behavior of the ;R command as
follows:
Value of N Action
+1 Gives control to the system-code debugger by simulating a call to
INI$BRK
+2 Returns to XDELTA after changing the password. 2;R without a
password is a no-op
0 Performs the default action
-1 Changes the password, breaks any existing connection to the System
Debugger and then simulates a call to INI$BRK (which will wait
for a new connection to be established and then give control to the
system-code debugger)
-2 Returns to XDELTA after changing the password and breaking an
existing connection
Currently, the default action is the same action as +1.
11–5