TOPS-20 PASCAL Language Manual - Bitsavers

CHAPTER 9
PASDDT: THE PASCAL-20 DEBUGGER
The PASCAL-20 debugger, P~SDDT, provides the means to monitor and
modify the execution of a PASCAL program. PASDDT provides symbolic
debugging capabilities that allow you to read and modify the values
associated with variables by referring to the PASCAL identifiers
within your program.
9.1 RUNNING PASDDT
To use the debugger, you must
program. First, compile the
switch in the command string:
compile and load PASDDT with the
source program and include the /DEBUG
@PASCAL
PASCAL>filename/DEBUG
PASCAL>/EXIT
@
Then, load the program along with PASDDT by specifying the DEBUG
command:
@DEBUG filename
The DEBUG command loads and starts the program
with the debugger, PASDDT.
currently in memory,
If you want more control over where the debugger is placed, or you
have the need for more options, you can use the TOPS-20 LINK program
directly. Refer to the LINK Reference Manual for TOPS-20 information.
When running PASDDT, the source file with the extension PAS should be
located in the same directory as the EXE version of the file. This
should also be the directory to which you are connected when running
PASDDT. If you have specified a file with the %INCLUDE directive,
PASDDT looks for a file with the same name.
9.2 USING SYMBOLIC VALUES
Symbolic values are the identifiers defined within the source program.
PASDDT allows access to identifiers available only in the current
scope, and performs recognition on these identifiers.
You can specify a location in the source code by using the line number
shown in the listing file created when the program is compiled. See
Section 8.4.7.
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