<s>
Turbo	B-Application
Debugger	I-Application
(	O
TD	O
)	O
is	O
a	O
machine-level	O
debugger	O
for	O
DOS	B-Device
executables	O
,	O
intended	O
mainly	O
for	O
debugging	O
Borland	O
Turbo	B-Application
Pascal	I-Application
,	O
and	O
later	O
Turbo	B-Application
C	I-Application
programs	O
,	O
sold	O
by	O
Borland	O
.	O
</s>
<s>
It	O
is	O
a	O
full-screen	O
debugger	O
displaying	O
both	O
Turbo	B-Application
Pascal	I-Application
or	O
Turbo	B-Application
C	I-Application
source	O
and	O
corresponding	O
assembly-language	O
instructions	O
,	O
with	O
powerful	O
capabilities	O
for	O
setting	O
breakpoints	O
,	O
watching	O
the	O
execution	O
of	O
instructions	O
,	O
monitoring	O
machine	O
registers	O
,	O
etc	O
.	O
</s>
<s>
Turbo	B-Application
Debugger	I-Application
can	O
be	O
used	O
for	O
programs	O
not	O
generated	O
by	O
Borland	O
compilers	O
,	O
but	O
without	O
showing	O
source	O
statements	O
;	O
it	O
is	O
by	O
no	O
means	O
the	O
only	O
debugger	O
available	O
for	O
non-Borland	O
executables	O
,	O
and	O
not	O
a	O
significant	O
general-purpose	O
debugger	O
.	O
</s>
<s>
Although	O
Borland	O
's	O
Turbo	B-Application
Pascal	I-Application
has	O
useful	O
single-stepping	O
and	O
conditional	O
breakpoint	O
facilities	O
,	O
the	O
need	O
for	O
a	O
more	O
powerful	O
debugger	O
became	O
apparent	O
when	O
Turbo	B-Application
Pascal	I-Application
started	O
to	O
be	O
used	O
for	O
serious	O
development	O
.	O
</s>
<s>
Initially	O
,	O
a	O
separate	O
company	O
,	O
TurboPower	O
Software	O
,	O
produced	O
a	O
debugger	O
,	O
T-Debug	O
,	O
and	O
also	O
their	O
Turbo	O
Analyst	O
and	O
Overlay	O
Manager	O
for	O
Turbo	B-Application
Pascal	I-Application
for	O
versions	O
1	O
to	O
3	O
.	O
</s>
<s>
TurboPower	O
released	O
T-Debug	O
Plus	O
4.0	O
for	O
Turbo	B-Application
Pascal	I-Application
4.0	O
in	O
1988	O
,	O
but	O
by	O
then	O
Borland	O
's	O
Turbo	B-Application
Debugger	I-Application
had	O
been	O
announced	O
.	O
</s>
<s>
The	O
original	O
Turbo	B-Application
Debugger	I-Application
was	O
sold	O
as	O
a	O
stand-alone	O
product	O
introduced	O
in	O
1989	O
,	O
along	O
with	O
Turbo	B-Application
Assembler	I-Application
and	O
the	O
second	O
version	O
of	O
Turbo	B-Application
C	I-Application
.	O
</s>
<s>
To	O
use	O
Turbo	B-Application
Debugger	I-Application
with	O
source	O
display	O
,	O
programs	O
,	O
or	O
relevant	O
parts	O
of	O
programs	O
,	O
must	O
be	O
compiled	O
with	O
Turbo	B-Application
Pascal	I-Application
or	O
Turbo	B-Application
C	I-Application
with	O
a	O
conditional	O
directive	O
set	O
to	O
add	O
debugging	O
information	O
to	O
the	O
compiled	O
executable	O
,	O
with	O
related	O
source	O
statements	O
and	O
corresponding	O
machine	O
code	O
.	O
</s>
<s>
The	O
debugger	O
can	O
then	O
be	O
started	O
(	O
Turbo	B-Application
Debugger	I-Application
does	O
not	O
debug	O
within	O
the	O
development	O
IDE	O
)	O
.	O
</s>
<s>
Later	O
Turbo	B-Application
Debugger	I-Application
,	O
the	O
stand-alone	O
Turbo	B-Application
Assembler	I-Application
(	O
TASM	B-Application
)	O
,	O
and	O
Turbo	B-Application
Profiler	I-Application
were	O
included	O
with	O
the	O
compilers	O
in	O
the	O
professional	O
Borland	B-Application
Pascal	I-Application
and	O
Borland	B-Application
C++	I-Application
versions	O
of	O
the	O
more	O
restricted	O
Turbo	B-Application
Pascal	I-Application
and	O
Turbo	O
C++	O
suites	O
for	O
DOS	B-Device
.	O
</s>
<s>
After	O
the	O
popularity	O
of	O
Microsoft	B-Application
Windows	I-Application
ended	O
the	O
era	O
of	O
DOS	B-Device
software	O
development	O
,	O
Turbo	B-Application
Debugger	I-Application
was	O
bundled	O
with	O
TASM	B-Application
for	O
low-level	B-Language
software	I-Language
development	O
.	O
</s>
<s>
For	O
many	O
years	O
after	O
the	O
end	O
of	O
the	O
DOS	B-Device
era	O
,	O
Borland	O
supplied	O
Turbo	B-Application
Debugger	I-Application
with	O
the	O
last	O
console-mode	O
Borland	B-Application
C++	I-Application
application	O
development	O
environment	O
,	O
version	O
5	O
,	O
and	O
with	O
Turbo	B-Application
Assembler	I-Application
5.0	O
.	O
</s>
<s>
With	O
Borland	O
's	O
reorganization	O
of	O
their	O
development	O
tools	O
as	O
CodeGear	O
,	O
all	O
references	O
to	O
Borland	B-Application
C++	I-Application
and	O
Turbo	B-Application
Assembler	I-Application
vanished	O
from	O
their	O
web	O
site	O
.	O
</s>
<s>
The	O
debuggers	O
in	O
later	O
products	O
such	O
as	O
C++Builder	B-Language
and	O
Delphi	B-Language
are	O
based	O
on	O
the	O
Windows	O
debugger	O
introduced	O
with	O
the	O
first	O
Borland	B-Application
C++	I-Application
and	O
Pascal	O
versions	O
for	O
Windows	O
.	O
</s>
<s>
The	O
final	O
version	O
of	O
Turbo	B-Application
Debugger	I-Application
came	O
with	O
several	O
versions	O
of	O
the	O
debugger	O
program	O
:	O
TD.EXE	B-Application
was	O
the	O
basic	O
debugger	O
;	O
TD286.EXE	B-Application
runs	O
in	O
protected	O
mode	O
,	O
and	O
TD386.EXE	B-Application
is	O
a	O
virtual	O
debugger	O
which	O
uses	O
the	O
TDH386.SYS	B-Application
device	B-Device
driver	O
to	O
communicate	O
with	O
TD.EXE	B-Application
.	O
</s>
<s>
The	O
TDH386.SYS	B-Application
driver	O
also	O
adds	O
breakpoints	O
supported	O
in	O
hardware	O
by	O
the	O
386	O
and	O
later	O
processors	O
to	O
all	O
three	O
debugger	O
programs	O
.	O
</s>
<s>
TD386	B-Application
allows	O
some	O
extra	O
breakpoints	O
that	O
the	O
other	O
debuggers	O
of	O
the	O
era	O
do	O
not	O
(	O
I/O	O
access	O
breaks	O
,	O
ranges	O
greater	O
than	O
16	O
bytes	B-Application
,	O
and	O
so	O
on	O
)	O
.	O
</s>
<s>
There	O
is	O
also	O
a	O
debugger	O
for	O
Windows	O
3	O
(	O
TDW.EXE	B-Application
)	O
.	O
</s>
<s>
BYTE	B-Application
in	O
1989	O
listed	O
Turbo	B-Application
Debugger	I-Application
as	O
among	O
the	O
"	O
Distinction	O
"	O
winners	O
of	O
the	O
BYTE	B-Application
Awards	O
.	O
</s>
<s>
Praising	O
its	O
ease	O
of	O
use	O
and	O
integration	O
with	O
Turbo	B-Application
Pascal	I-Application
and	O
Turbo	B-Application
C	I-Application
,	O
the	O
magazine	O
described	O
it	O
as	O
"	O
a	O
programmer	O
's	O
Swiss	O
army	O
knife	O
"	O
.	O
</s>
<s>
Various	O
versions	O
of	O
Turbo	B-Application
Assembler	I-Application
,	O
spanning	O
from	O
version	O
1.0	O
through	O
5.0	O
,	O
have	O
been	O
reported	O
to	O
run	O
on	O
the	O
DOSBox	B-Application
emulator	O
,	O
which	O
emulates	O
DOS	B-Device
5.0	O
.	O
</s>
<s>
The	O
last	O
DOS	B-Device
release	O
of	O
TD.EXE	B-Application
,	O
version	O
3.2	O
,	O
runs	O
successfully	O
in	O
the	O
32-bit	B-Application
Windows	I-Application
XP	B-Application
NTVDM	O
(	O
i.e.	O
,	O
in	O
a	O
DOS	B-Device
window	O
,	O
invoked	O
with	O
CMD.EXE	B-Device
)	O
,	O
but	O
TD286.EXE	B-Application
and	O
TD386.EXE	B-Application
do	O
not	O
.	O
</s>
<s>
Hardware	O
breakpoints	O
supported	O
by	O
the	O
386	O
and	O
later	O
processors	O
are	O
available	O
if	O
TDH386.SYS	B-Application
is	O
loaded	O
by	O
including	O
"	O
DEVICE	B-Device
=	O
<	O
path>TDH386.SYS	O
"	O
in	O
a	O
CONFIG.NT	B-Device
file	O
invoked	O
when	O
running	O
TD.EXE	B-Application
.	O
</s>
