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1 | @c -*- Texinfo -*- |
2 | @c Copyright (c) 1990 1991 1992 1993 Free Software Foundation, Inc. | |
3 | @c This file is part of the source for the GDB manual. | |
4 | @c This text diverted to "Remote Debugging" section in general case; | |
5 | @c however, if we're doing a manual specifically for one of these, it | |
6 | @c belongs up front (in "Getting In and Out" chapter). | |
7 | ||
8 | @ifset REMOTESTUB | |
9 | @node Remote Serial | |
10 | @subsection The @value{GDBN} remote serial protocol | |
11 | ||
12 | @cindex remote serial debugging, overview | |
13 | To debug a program running on another machine (the debugging | |
14 | @dfn{target} machine), you must first arrange for all the usual | |
15 | prerequisites for the program to run by itself. For example, for a C | |
af215b1a | 16 | program, you need: |
4af6d502 RP |
17 | |
18 | @enumerate | |
19 | @item | |
20 | A startup routine to set up the C runtime environment; these usually | |
21 | have a name like @file{crt0}. The startup routine may be supplied by | |
22 | your hardware supplier, or you may have to write your own. | |
23 | ||
24 | @item | |
25 | You probably need a C subroutine library to support your program's | |
26 | subroutine calls, notably managing input and output. | |
27 | ||
28 | @item | |
29 | A way of getting your program to the other machine---for example, a | |
30 | download program. These are often supplied by the hardware | |
31 | manufacturer, but you may have to write your own from hardware | |
32 | documentation. | |
33 | @end enumerate | |
34 | ||
35 | The next step is to arrange for your program to use a serial port to | |
36 | communicate with the machine where @value{GDBN} is running (the @dfn{host} | |
37 | machine). In general terms, the scheme looks like this: | |
38 | ||
39 | @table @emph | |
40 | @item On the host, | |
41 | @value{GDBN} already understands how to use this protocol; when everything | |
42 | else is set up, you can simply use the @samp{target remote} command | |
43 | (@pxref{Targets,,Specifying a Debugging Target}). | |
44 | ||
45 | @item On the target, | |
46 | you must link with your program a few special-purpose subroutines that | |
47 | implement the @value{GDBN} remote serial protocol. The file containing these | |
48 | subroutines is called a @dfn{debugging stub}. | |
49 | ||
50 | @ifset GDBSERVER | |
51 | On certain remote targets, you can use an auxiliary program | |
52 | @code{gdbserver} instead of linking a stub into your program. | |
53 | @xref{Server,,Using the @code{gdbserver} program}, for details. | |
54 | @end ifset | |
55 | @end table | |
56 | ||
57 | The debugging stub is specific to the architecture of the remote | |
58 | machine; for example, use @file{sparc-stub.c} to debug programs on | |
59 | @sc{sparc} boards. | |
60 | ||
61 | @cindex remote serial stub list | |
62 | These working remote stubs are distributed with @value{GDBN}: | |
63 | ||
64 | @table @code | |
65 | @item sparc-stub.c | |
66 | @kindex sparc-stub.c | |
67 | For @sc{sparc} architectures. | |
68 | ||
69 | @item m68k-stub.c | |
70 | @kindex m68k-stub.c | |
6b51acad | 71 | @cindex Motorola 680x0 |
02f868b1 | 72 | @cindex m680x0 |
4af6d502 RP |
73 | For Motorola 680x0 architectures. |
74 | ||
75 | @item i386-stub.c | |
76 | @kindex i386-stub.c | |
6b51acad | 77 | @cindex Intel |
02f868b1 | 78 | @cindex i386 |
4af6d502 RP |
79 | For Intel 386 and compatible architectures. |
80 | @end table | |
81 | ||
82 | The @file{README} file in the @value{GDBN} distribution may list other | |
83 | recently added stubs. | |
84 | ||
85 | @menu | |
86 | * Stub Contents:: What the stub can do for you | |
87 | * Bootstrapping:: What you must do for the stub | |
88 | * Debug Session:: Putting it all together | |
89 | * Protocol:: Outline of the communication protocol | |
90 | @ifset GDBSERVER | |
91 | * Server:: Using the `gdbserver' program | |
92 | @end ifset | |
07dff010 C |
93 | @ifset GDBSERVE |
94 | * NetWare:: Using the `gdbserve.nlm' program | |
95 | @end ifset | |
4af6d502 RP |
96 | @end menu |
97 | ||
98 | @node Stub Contents | |
99 | @subsubsection What the stub can do for you | |
100 | ||
101 | @cindex remote serial stub | |
102 | The debugging stub for your architecture supplies these three | |
103 | subroutines: | |
104 | ||
105 | @table @code | |
106 | @item set_debug_traps | |
107 | @kindex set_debug_traps | |
108 | @cindex remote serial stub, initialization | |
109 | This routine arranges for @code{handle_exception} to run when your | |
110 | program stops. You must call this subroutine explicitly near the | |
111 | beginning of your program. | |
112 | ||
113 | @item handle_exception | |
114 | @kindex handle_exception | |
115 | @cindex remote serial stub, main routine | |
116 | This is the central workhorse, but your program never calls it | |
117 | explicitly---the setup code arranges for @code{handle_exception} to | |
118 | run when a trap is triggered. | |
119 | ||
120 | @code{handle_exception} takes control when your program stops during | |
121 | execution (for example, on a breakpoint), and mediates communications | |
122 | with @value{GDBN} on the host machine. This is where the communications | |
123 | protocol is implemented; @code{handle_exception} acts as the @value{GDBN} | |
124 | representative on the target machine; it begins by sending summary | |
125 | information on the state of your program, then continues to execute, | |
126 | retrieving and transmitting any information @value{GDBN} needs, until you | |
127 | execute a @value{GDBN} command that makes your program resume; at that point, | |
128 | @code{handle_exception} returns control to your own code on the target | |
129 | machine. | |
130 | ||
131 | @item breakpoint | |
132 | @cindex @code{breakpoint} subroutine, remote | |
133 | Use this auxiliary subroutine to make your program contain a | |
134 | breakpoint. Depending on the particular situation, this may be the only | |
135 | way for @value{GDBN} to get control. For instance, if your target | |
136 | machine has some sort of interrupt button, you won't need to call this; | |
9a27b06e | 137 | pressing the interrupt button transfers control to |
4af6d502 RP |
138 | @code{handle_exception}---in effect, to @value{GDBN}. On some machines, |
139 | simply receiving characters on the serial port may also trigger a trap; | |
140 | again, in that situation, you don't need to call @code{breakpoint} from | |
141 | your own program---simply running @samp{target remote} from the host | |
9a27b06e | 142 | @value{GDBN} session gets control. |
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143 | |
144 | Call @code{breakpoint} if none of these is true, or if you simply want | |
145 | to make certain your program stops at a predetermined point for the | |
146 | start of your debugging session. | |
147 | @end table | |
148 | ||
149 | @node Bootstrapping | |
150 | @subsubsection What you must do for the stub | |
151 | ||
152 | @cindex remote stub, support routines | |
153 | The debugging stubs that come with @value{GDBN} are set up for a particular | |
154 | chip architecture, but they have no information about the rest of your | |
e3b9a485 JK |
155 | debugging target machine. |
156 | ||
157 | First of all you need to tell the stub how to communicate with the | |
158 | serial port. | |
4af6d502 RP |
159 | |
160 | @table @code | |
161 | @item int getDebugChar() | |
162 | @kindex getDebugChar | |
163 | Write this subroutine to read a single character from the serial port. | |
164 | It may be identical to @code{getchar} for your target system; a | |
165 | different name is used to allow you to distinguish the two if you wish. | |
166 | ||
167 | @item void putDebugChar(int) | |
168 | @kindex putDebugChar | |
169 | Write this subroutine to write a single character to the serial port. | |
170 | It may be identical to @code{putchar} for your target system; a | |
171 | different name is used to allow you to distinguish the two if you wish. | |
e3b9a485 JK |
172 | @end table |
173 | ||
22b5dba5 RP |
174 | @cindex control C, and remote debugging |
175 | @cindex interrupting remote targets | |
e3b9a485 JK |
176 | If you want @value{GDBN} to be able to stop your program while it is |
177 | running, you need to use an interrupt-driven serial driver, and arrange | |
22b5dba5 RP |
178 | for it to stop when it receives a @code{^C} (@samp{\003}, the control-C |
179 | character). That is the character which @value{GDBN} uses to tell the | |
180 | remote system to stop. | |
181 | ||
182 | Getting the debugging target to return the proper status to @value{GDBN} | |
183 | probably requires changes to the standard stub; one quick and dirty way | |
184 | is to just execute a breakpoint instruction (the ``dirty'' part is that | |
185 | @value{GDBN} reports a @code{SIGTRAP} instead of a @code{SIGINT}). | |
4af6d502 | 186 | |
e3b9a485 JK |
187 | Other routines you need to supply are: |
188 | ||
189 | @table @code | |
4af6d502 | 190 | @item void exceptionHandler (int @var{exception_number}, void *@var{exception_address}) |
8d8c5f39 | 191 | @kindex exceptionHandler |
4af6d502 RP |
192 | Write this function to install @var{exception_address} in the exception |
193 | handling tables. You need to do this because the stub does not have any | |
194 | way of knowing what the exception handling tables on your target system | |
195 | are like (for example, the processor's table might be in @sc{rom}, | |
196 | containing entries which point to a table in @sc{ram}). | |
197 | @var{exception_number} is the exception number which should be changed; | |
198 | its meaning is architecture-dependent (for example, different numbers | |
199 | might represent divide by zero, misaligned access, etc). When this | |
200 | exception occurs, control should be transferred directly to | |
201 | @var{exception_address}, and the processor state (stack, registers, | |
b1955f0b | 202 | and so on) should be just as it is when a processor exception occurs. So if |
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203 | you want to use a jump instruction to reach @var{exception_address}, it |
204 | should be a simple jump, not a jump to subroutine. | |
205 | ||
4af6d502 | 206 | For the 386, @var{exception_address} should be installed as an interrupt |
8d8c5f39 JK |
207 | gate so that interrupts are masked while the handler runs. The gate |
208 | should be at privilege level 0 (the most privileged level). The | |
af215b1a | 209 | @sc{sparc} and 68k stubs are able to mask interrup themselves without |
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210 | help from @code{exceptionHandler}. |
211 | ||
212 | @item void flush_i_cache() | |
213 | @kindex flush_i_cache | |
0f6bb717 JK |
214 | (sparc and sparclite only) Write this subroutine to flush the |
215 | instruction cache, if any, on your target machine. If there is no | |
216 | instruction cache, this subroutine may be a no-op. | |
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217 | |
218 | On target machines that have instruction caches, @value{GDBN} requires this | |
219 | function to make certain that the state of your program is stable. | |
220 | @end table | |
221 | ||
222 | @noindent | |
223 | You must also make sure this library routine is available: | |
224 | ||
225 | @table @code | |
226 | @item void *memset(void *, int, int) | |
227 | @kindex memset | |
228 | This is the standard library function @code{memset} that sets an area of | |
229 | memory to a known value. If you have one of the free versions of | |
230 | @code{libc.a}, @code{memset} can be found there; otherwise, you must | |
231 | either obtain it from your hardware manufacturer, or write your own. | |
232 | @end table | |
233 | ||
234 | If you do not use the GNU C compiler, you may need other standard | |
9a27b06e | 235 | library subroutines as well; this varies from one stub to another, |
4af6d502 RP |
236 | but in general the stubs are likely to use any of the common library |
237 | subroutines which @code{gcc} generates as inline code. | |
238 | ||
239 | ||
240 | @node Debug Session | |
241 | @subsubsection Putting it all together | |
242 | ||
243 | @cindex remote serial debugging summary | |
244 | In summary, when your program is ready to debug, you must follow these | |
245 | steps. | |
246 | ||
247 | @enumerate | |
248 | @item | |
249 | Make sure you have the supporting low-level routines | |
6b51acad | 250 | (@pxref{Bootstrapping,,What you must do for the stub}): |
4af6d502 RP |
251 | @display |
252 | @code{getDebugChar}, @code{putDebugChar}, | |
253 | @code{flush_i_cache}, @code{memset}, @code{exceptionHandler}. | |
254 | @end display | |
255 | ||
256 | @item | |
257 | Insert these lines near the top of your program: | |
258 | ||
259 | @example | |
260 | set_debug_traps(); | |
261 | breakpoint(); | |
262 | @end example | |
263 | ||
264 | @item | |
265 | For the 680x0 stub only, you need to provide a variable called | |
af215b1a | 266 | @code{exceptionHook}. Normally you just use: |
4af6d502 RP |
267 | |
268 | @example | |
269 | void (*exceptionHook)() = 0; | |
270 | @end example | |
271 | ||
272 | but if before calling @code{set_debug_traps}, you set it to point to a | |
273 | function in your program, that function is called when | |
274 | @code{@value{GDBN}} continues after stopping on a trap (for example, bus | |
275 | error). The function indicated by @code{exceptionHook} is called with | |
276 | one parameter: an @code{int} which is the exception number. | |
277 | ||
278 | @item | |
279 | Compile and link together: your program, the @value{GDBN} debugging stub for | |
280 | your target architecture, and the supporting subroutines. | |
281 | ||
282 | @item | |
283 | Make sure you have a serial connection between your target machine and | |
af215b1a | 284 | the @value{GDBN} host, and identify the serial port on the host. |
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285 | |
286 | @item | |
287 | @c The "remote" target now provides a `load' command, so we should | |
288 | @c document that. FIXME. | |
289 | Download your program to your target machine (or get it there by | |
290 | whatever means the manufacturer provides), and start it. | |
291 | ||
292 | @item | |
293 | To start remote debugging, run @value{GDBN} on the host machine, and specify | |
294 | as an executable file the program that is running in the remote machine. | |
295 | This tells @value{GDBN} how to find your program's symbols and the contents | |
296 | of its pure text. | |
297 | ||
298 | @cindex serial line, @code{target remote} | |
299 | Then establish communication using the @code{target remote} command. | |
300 | Its argument specifies how to communicate with the target | |
301 | machine---either via a devicename attached to a direct serial line, or a | |
302 | TCP port (usually to a terminal server which in turn has a serial line | |
303 | to the target). For example, to use a serial line connected to the | |
304 | device named @file{/dev/ttyb}: | |
305 | ||
306 | @example | |
307 | target remote /dev/ttyb | |
308 | @end example | |
309 | ||
310 | @cindex TCP port, @code{target remote} | |
311 | To use a TCP connection, use an argument of the form | |
312 | @code{@var{host}:port}. For example, to connect to port 2828 on a | |
313 | terminal server named @code{manyfarms}: | |
314 | ||
315 | @example | |
316 | target remote manyfarms:2828 | |
317 | @end example | |
318 | @end enumerate | |
319 | ||
320 | Now you can use all the usual commands to examine and change data and to | |
321 | step and continue the remote program. | |
322 | ||
323 | To resume the remote program and stop debugging it, use the @code{detach} | |
324 | command. | |
325 | ||
326 | @cindex interrupting remote programs | |
327 | @cindex remote programs, interrupting | |
328 | Whenever @value{GDBN} is waiting for the remote program, if you type the | |
329 | interrupt character (often @key{C-C}), @value{GDBN} attempts to stop the | |
330 | program. This may or may not succeed, depending in part on the hardware | |
331 | and the serial drivers the remote system uses. If you type the | |
332 | interrupt character once again, @value{GDBN} displays this prompt: | |
333 | ||
334 | @example | |
335 | Interrupted while waiting for the program. | |
336 | Give up (and stop debugging it)? (y or n) | |
337 | @end example | |
338 | ||
339 | If you type @kbd{y}, @value{GDBN} abandons the remote debugging session. | |
340 | (If you decide you want to try again later, you can use @samp{target | |
341 | remote} again to connect once more.) If you type @kbd{n}, @value{GDBN} | |
342 | goes back to waiting. | |
343 | ||
344 | @node Protocol | |
b1955f0b | 345 | @subsubsection Communication protocol |
4af6d502 RP |
346 | |
347 | @cindex debugging stub, example | |
348 | @cindex remote stub, example | |
349 | @cindex stub example, remote debugging | |
350 | The stub files provided with @value{GDBN} implement the target side of the | |
351 | communication protocol, and the @value{GDBN} side is implemented in the | |
352 | @value{GDBN} source file @file{remote.c}. Normally, you can simply allow | |
353 | these subroutines to communicate, and ignore the details. (If you're | |
354 | implementing your own stub file, you can still ignore the details: start | |
355 | with one of the existing stub files. @file{sparc-stub.c} is the best | |
356 | organized, and therefore the easiest to read.) | |
357 | ||
358 | However, there may be occasions when you need to know something about | |
359 | the protocol---for example, if there is only one serial port to your | |
360 | target machine, you might want your program to do something special if | |
361 | it recognizes a packet meant for @value{GDBN}. | |
362 | ||
363 | @cindex protocol, @value{GDBN} remote serial | |
364 | @cindex serial protocol, @value{GDBN} remote | |
365 | @cindex remote serial protocol | |
366 | All @value{GDBN} commands and responses (other than acknowledgements, which | |
367 | are single characters) are sent as a packet which includes a | |
368 | checksum. A packet is introduced with the character @samp{$}, and ends | |
369 | with the character @samp{#} followed by a two-digit checksum: | |
370 | ||
371 | @example | |
372 | $@var{packet info}#@var{checksum} | |
373 | @end example | |
374 | ||
375 | @cindex checksum, for @value{GDBN} remote | |
376 | @noindent | |
377 | @var{checksum} is computed as the modulo 256 sum of the @var{packet | |
378 | info} characters. | |
379 | ||
380 | When either the host or the target machine receives a packet, the first | |
381 | response expected is an acknowledgement: a single character, either | |
382 | @samp{+} (to indicate the package was received correctly) or @samp{-} | |
383 | (to request retransmission). | |
384 | ||
385 | The host (@value{GDBN}) sends commands, and the target (the debugging stub | |
386 | incorporated in your program) sends data in response. The target also | |
387 | sends data when your program stops. | |
388 | ||
389 | Command packets are distinguished by their first character, which | |
390 | identifies the kind of command. | |
391 | ||
af215b1a VM |
392 | These are some of the commands currently supported (for a complete list of |
393 | commands, look in @file{gdb/remote.c.}): | |
4af6d502 RP |
394 | |
395 | @table @code | |
396 | @item g | |
397 | Requests the values of CPU registers. | |
398 | ||
399 | @item G | |
400 | Sets the values of CPU registers. | |
401 | ||
402 | @item m@var{addr},@var{count} | |
403 | Read @var{count} bytes at location @var{addr}. | |
404 | ||
405 | @item M@var{addr},@var{count}:@dots{} | |
406 | Write @var{count} bytes at location @var{addr}. | |
407 | ||
b1955f0b | 408 | @need 500 |
4af6d502 RP |
409 | @item c |
410 | @itemx c@var{addr} | |
411 | Resume execution at the current address (or at @var{addr} if supplied). | |
412 | ||
b1955f0b | 413 | @need 500 |
4af6d502 RP |
414 | @item s |
415 | @itemx s@var{addr} | |
416 | Step the target program for one instruction, from either the current | |
417 | program counter or from @var{addr} if supplied. | |
418 | ||
419 | @item k | |
420 | Kill the target program. | |
421 | ||
422 | @item ? | |
423 | Report the most recent signal. To allow you to take advantage of the | |
424 | @value{GDBN} signal handling commands, one of the functions of the debugging | |
425 | stub is to report CPU traps as the corresponding POSIX signal values. | |
af215b1a VM |
426 | |
427 | @item T | |
428 | Allows the remote stub to send only the registers that @value{GDBN} needs | |
429 | to make a quick decision about single-stepping or conditional breakpoints. | |
430 | This eliminates the need to fetch the entire register set for each instruction | |
431 | being stepped through. | |
432 | ||
433 | The @value{GDBN} remote serial protocol now implements a write-through | |
434 | cache for registers. @value{GDBN} only re-reads the registers if the | |
435 | target has run. | |
4af6d502 RP |
436 | @end table |
437 | ||
438 | @kindex set remotedebug | |
439 | @kindex show remotedebug | |
440 | @cindex packets, reporting on stdout | |
441 | @cindex serial connections, debugging | |
442 | If you have trouble with the serial connection, you can use the command | |
443 | @code{set remotedebug}. This makes @value{GDBN} report on all packets sent | |
444 | back and forth across the serial line to the remote machine. The | |
445 | packet-debugging information is printed on the @value{GDBN} standard output | |
446 | stream. @code{set remotedebug off} turns it off, and @code{show | |
9a27b06e | 447 | remotedebug} shows you its current state. |
4af6d502 RP |
448 | |
449 | @ifset GDBSERVER | |
450 | @node Server | |
451 | @subsubsection Using the @code{gdbserver} program | |
452 | ||
453 | @kindex gdbserver | |
454 | @cindex remote connection without stubs | |
455 | @code{gdbserver} is a control program for Unix-like systems, which | |
456 | allows you to connect your program with a remote @value{GDBN} via | |
457 | @code{target remote}---but without linking in the usual debugging stub. | |
458 | ||
459 | @code{gdbserver} is not a complete replacement for the debugging stubs, | |
460 | because it requires essentially the same operating-system facilities | |
461 | that @value{GDBN} itself does. In fact, a system that can run | |
462 | @code{gdbserver} to connect to a remote @value{GDBN} could also run | |
c79890ee | 463 | @value{GDBN} locally! @code{gdbserver} is sometimes useful nevertheless, |
4af6d502 | 464 | because it is a much smaller program than @value{GDBN} itself. It is |
c79890ee | 465 | also easier to port than all of @value{GDBN}, so you may be able to get |
4af6d502 | 466 | started more quickly on a new system by using @code{gdbserver}. |
22b5dba5 RP |
467 | Finally, if you develop code for real-time systems, you may find that |
468 | the tradeoffs involved in real-time operation make it more convenient to | |
469 | do as much development work as possible on another system, for example | |
470 | by cross-compiling. You can use @code{gdbserver} to make a similar | |
471 | choice for debugging. | |
4af6d502 RP |
472 | |
473 | @value{GDBN} and @code{gdbserver} communicate via either a serial line | |
474 | or a TCP connection, using the standard @value{GDBN} remote serial | |
475 | protocol. | |
476 | ||
477 | @table @emph | |
22b5dba5 | 478 | @item On the target machine, |
4af6d502 RP |
479 | you need to have a copy of the program you want to debug. |
480 | @code{gdbserver} does not need your program's symbol table, so you can | |
481 | strip the program if necessary to save space. @value{GDBN} on the host | |
482 | system does all the symbol handling. | |
483 | ||
22b5dba5 | 484 | To use the server, you must tell it how to communicate with @value{GDBN}; |
4af6d502 RP |
485 | the name of your program; and the arguments for your program. The |
486 | syntax is: | |
487 | ||
488 | @smallexample | |
489 | target> gdbserver @var{comm} @var{program} [ @var{args} @dots{} ] | |
490 | @end smallexample | |
491 | ||
492 | @var{comm} is either a device name (to use a serial line) or a TCP | |
22b5dba5 | 493 | hostname and portnumber. For example, to debug Emacs with the argument |
4af6d502 RP |
494 | @samp{foo.txt} and communicate with @value{GDBN} over the serial port |
495 | @file{/dev/com1}: | |
496 | ||
497 | @smallexample | |
498 | target> gdbserver /dev/com1 emacs foo.txt | |
499 | @end smallexample | |
500 | ||
501 | @code{gdbserver} waits passively for the host @value{GDBN} to communicate | |
502 | with it. | |
503 | ||
504 | To use a TCP connection instead of a serial line: | |
505 | ||
506 | @smallexample | |
507 | target> gdbserver host:2345 emacs foo.txt | |
508 | @end smallexample | |
509 | ||
510 | The only difference from the previous example is the first argument, | |
511 | specifying that you are communicating with the host @value{GDBN} via | |
512 | TCP. The @samp{host:2345} argument means that @code{gdbserver} is to | |
513 | expect a TCP connection from machine @samp{host} to local TCP port 2345. | |
514 | (Currently, the @samp{host} part is ignored.) You can choose any number | |
515 | you want for the port number as long as it does not conflict with any | |
22b5dba5 RP |
516 | TCP ports already in use on the target system (for example, @code{23} is |
517 | reserved for @code{telnet}).@footnote{If you choose a port number that | |
518 | conflicts with another service, @code{gdbserver} prints an error message | |
519 | and exits.} You must use the same port number with the host @value{GDBN} | |
520 | @code{target remote} command. | |
521 | ||
522 | @item On the @value{GDBN} host machine, | |
523 | you need an unstripped copy of your program, since @value{GDBN} needs | |
524 | symbols and debugging information. Start up @value{GDBN} as usual, | |
525 | using the name of the local copy of your program as the first argument. | |
526 | (You may also need the @w{@samp{--baud}} option if the serial line is | |
527 | running at anything other than 9600 bps.) After that, use @code{target | |
528 | remote} to establish communications with @code{gdbserver}. Its argument | |
529 | is either a device name (usually a serial device, like | |
530 | @file{/dev/ttyb}), or a TCP port descriptor in the form | |
531 | @code{@var{host}:@var{PORT}}. For example: | |
4af6d502 RP |
532 | |
533 | @smallexample | |
534 | (@value{GDBP}) target remote /dev/ttyb | |
535 | @end smallexample | |
536 | ||
537 | @noindent | |
538 | communicates with the server via serial line @file{/dev/ttyb}, and | |
539 | ||
540 | @smallexample | |
541 | (@value{GDBP}) target remote the-target:2345 | |
542 | @end smallexample | |
543 | ||
544 | @noindent | |
22b5dba5 | 545 | communicates via a TCP connection to port 2345 on host @w{@file{the-target}}. |
4af6d502 RP |
546 | For TCP connections, you must start up @code{gdbserver} prior to using |
547 | the @code{target remote} command. Otherwise you may get an error whose | |
548 | text depends on the host system, but which usually looks something like | |
549 | @samp{Connection refused}. | |
550 | @end table | |
551 | @end ifset | |
552 | ||
07dff010 C |
553 | @ifset GDBSERVE |
554 | @node NetWare | |
555 | @subsubsection Using the @code{gdbserve.nlm} program | |
556 | ||
557 | @kindex gdbserve.nlm | |
558 | @code{gdbserve.nlm} is a control program for NetWare systems, which | |
559 | allows you to connect your program with a remote @value{GDBN} via | |
560 | @code{target remote}. | |
561 | ||
562 | @value{GDBN} and @code{gdbserve.nlm} communicate via a serial line, | |
563 | using the standard @value{GDBN} remote serial protocol. | |
564 | ||
565 | @table @emph | |
566 | @item On the target machine, | |
567 | you need to have a copy of the program you want to debug. | |
568 | @code{gdbserve.nlm} does not need your program's symbol table, so you | |
569 | can strip the program if necessary to save space. @value{GDBN} on the | |
570 | host system does all the symbol handling. | |
571 | ||
572 | To use the server, you must tell it how to communicate with | |
573 | @value{GDBN}; the name of your program; and the arguments for your | |
574 | program. The syntax is: | |
575 | ||
576 | @smallexample | |
af215b1a VM |
577 | load gdbserve [ BOARD=@var{board} ] [ PORT=@var{port} ] |
578 | [ BAUD=@var{baud} ] @var{program} [ @var{args} @dots{} ] | |
07dff010 C |
579 | @end smallexample |
580 | ||
7d777b91 | 581 | @var{board} and @var{port} specify the serial line; @var{baud} specifies |
07dff010 C |
582 | the baud rate used by the connection. @var{port} and @var{node} default |
583 | to 0, @var{baud} defaults to 9600 bps. | |
584 | ||
585 | For example, to debug Emacs with the argument @samp{foo.txt}and | |
7d777b91 C |
586 | communicate with @value{GDBN} over serial port number 2 or board 1 |
587 | using a 19200 bps connection: | |
07dff010 C |
588 | |
589 | @smallexample | |
7d777b91 | 590 | load gdbserve BOARD=1 PORT=2 BAUD=19200 emacs foo.txt |
07dff010 C |
591 | @end smallexample |
592 | ||
593 | @item On the @value{GDBN} host machine, | |
594 | you need an unstripped copy of your program, since @value{GDBN} needs | |
595 | symbols and debugging information. Start up @value{GDBN} as usual, | |
596 | using the name of the local copy of your program as the first argument. | |
597 | (You may also need the @w{@samp{--baud}} option if the serial line is | |
598 | running at anything other than 9600 bps. After that, use @code{target | |
599 | remote} to establish communications with @code{gdbserve.nlm}. Its | |
600 | argument is a device name (usually a serial device, like | |
601 | @file{/dev/ttyb}). For example: | |
602 | ||
603 | @smallexample | |
604 | (@value{GDBP}) target remote /dev/ttyb | |
605 | @end smallexample | |
606 | ||
607 | @noindent | |
608 | communications with the server via serial line @file{/dev/ttyb}. | |
609 | @end table | |
610 | @end ifset | |
611 | ||
4af6d502 RP |
612 | @end ifset |
613 | ||
614 | @ifset I960 | |
615 | @node i960-Nindy Remote | |
616 | @subsection @value{GDBN} with a remote i960 (Nindy) | |
617 | ||
618 | @cindex Nindy | |
619 | @cindex i960 | |
620 | @dfn{Nindy} is a ROM Monitor program for Intel 960 target systems. When | |
621 | @value{GDBN} is configured to control a remote Intel 960 using Nindy, you can | |
622 | tell @value{GDBN} how to connect to the 960 in several ways: | |
623 | ||
624 | @itemize @bullet | |
625 | @item | |
626 | Through command line options specifying serial port, version of the | |
627 | Nindy protocol, and communications speed; | |
628 | ||
629 | @item | |
630 | By responding to a prompt on startup; | |
631 | ||
632 | @item | |
633 | By using the @code{target} command at any point during your @value{GDBN} | |
634 | session. @xref{Target Commands, ,Commands for managing targets}. | |
635 | ||
636 | @end itemize | |
637 | ||
638 | @menu | |
639 | * Nindy Startup:: Startup with Nindy | |
640 | * Nindy Options:: Options for Nindy | |
641 | * Nindy Reset:: Nindy reset command | |
642 | @end menu | |
643 | ||
644 | @node Nindy Startup | |
645 | @subsubsection Startup with Nindy | |
646 | ||
647 | If you simply start @code{@value{GDBP}} without using any command-line | |
648 | options, you are prompted for what serial port to use, @emph{before} you | |
649 | reach the ordinary @value{GDBN} prompt: | |
650 | ||
651 | @example | |
652 | Attach /dev/ttyNN -- specify NN, or "quit" to quit: | |
653 | @end example | |
654 | ||
655 | @noindent | |
656 | Respond to the prompt with whatever suffix (after @samp{/dev/tty}) | |
657 | identifies the serial port you want to use. You can, if you choose, | |
658 | simply start up with no Nindy connection by responding to the prompt | |
659 | with an empty line. If you do this and later wish to attach to Nindy, | |
660 | use @code{target} (@pxref{Target Commands, ,Commands for managing targets}). | |
661 | ||
662 | @node Nindy Options | |
663 | @subsubsection Options for Nindy | |
664 | ||
665 | These are the startup options for beginning your @value{GDBN} session with a | |
666 | Nindy-960 board attached: | |
667 | ||
668 | @table @code | |
669 | @item -r @var{port} | |
670 | Specify the serial port name of a serial interface to be used to connect | |
671 | to the target system. This option is only available when @value{GDBN} is | |
672 | configured for the Intel 960 target architecture. You may specify | |
673 | @var{port} as any of: a full pathname (e.g. @samp{-r /dev/ttya}), a | |
674 | device name in @file{/dev} (e.g. @samp{-r ttya}), or simply the unique | |
675 | suffix for a specific @code{tty} (e.g. @samp{-r a}). | |
676 | ||
677 | @item -O | |
678 | (An uppercase letter ``O'', not a zero.) Specify that @value{GDBN} should use | |
679 | the ``old'' Nindy monitor protocol to connect to the target system. | |
680 | This option is only available when @value{GDBN} is configured for the Intel 960 | |
681 | target architecture. | |
682 | ||
683 | @quotation | |
684 | @emph{Warning:} if you specify @samp{-O}, but are actually trying to | |
685 | connect to a target system that expects the newer protocol, the connection | |
686 | fails, appearing to be a speed mismatch. @value{GDBN} repeatedly | |
687 | attempts to reconnect at several different line speeds. You can abort | |
688 | this process with an interrupt. | |
689 | @end quotation | |
690 | ||
691 | @item -brk | |
692 | Specify that @value{GDBN} should first send a @code{BREAK} signal to the target | |
693 | system, in an attempt to reset it, before connecting to a Nindy target. | |
694 | ||
695 | @quotation | |
696 | @emph{Warning:} Many target systems do not have the hardware that this | |
697 | requires; it only works with a few boards. | |
698 | @end quotation | |
699 | @end table | |
700 | ||
701 | The standard @samp{-b} option controls the line speed used on the serial | |
702 | port. | |
703 | ||
704 | @c @group | |
705 | @node Nindy Reset | |
706 | @subsubsection Nindy reset command | |
707 | ||
708 | @table @code | |
709 | @item reset | |
710 | @kindex reset | |
711 | For a Nindy target, this command sends a ``break'' to the remote target | |
712 | system; this is only useful if the target has been equipped with a | |
713 | circuit to perform a hard reset (or some other interesting action) when | |
714 | a break is detected. | |
715 | @end table | |
716 | @c @end group | |
717 | @end ifset | |
718 | ||
719 | @ifset AMD29K | |
720 | @node UDI29K Remote | |
b1955f0b | 721 | @subsection The UDI protocol for AMD29K |
4af6d502 RP |
722 | |
723 | @cindex UDI | |
724 | @cindex AMD29K via UDI | |
725 | @value{GDBN} supports AMD's UDI (``Universal Debugger Interface'') | |
726 | protocol for debugging the a29k processor family. To use this | |
727 | configuration with AMD targets running the MiniMON monitor, you need the | |
728 | program @code{MONTIP}, available from AMD at no charge. You can also | |
af215b1a | 729 | use @value{GDBN} with the UDI-conformant a29k simulator program |
4af6d502 RP |
730 | @code{ISSTIP}, also available from AMD. |
731 | ||
732 | @table @code | |
733 | @item target udi @var{keyword} | |
734 | @kindex udi | |
735 | Select the UDI interface to a remote a29k board or simulator, where | |
736 | @var{keyword} is an entry in the AMD configuration file @file{udi_soc}. | |
737 | This file contains keyword entries which specify parameters used to | |
738 | connect to a29k targets. If the @file{udi_soc} file is not in your | |
739 | working directory, you must set the environment variable @samp{UDICONF} | |
740 | to its pathname. | |
741 | @end table | |
742 | ||
743 | @node EB29K Remote | |
b1955f0b | 744 | @subsection The EBMON protocol for AMD29K |
4af6d502 RP |
745 | |
746 | @cindex EB29K board | |
747 | @cindex running 29K programs | |
748 | ||
749 | AMD distributes a 29K development board meant to fit in a PC, together | |
750 | with a DOS-hosted monitor program called @code{EBMON}. As a shorthand | |
751 | term, this development system is called the ``EB29K''. To use | |
752 | @value{GDBN} from a Unix system to run programs on the EB29K board, you | |
753 | must first connect a serial cable between the PC (which hosts the EB29K | |
754 | board) and a serial port on the Unix system. In the following, we | |
755 | assume you've hooked the cable between the PC's @file{COM1} port and | |
756 | @file{/dev/ttya} on the Unix system. | |
757 | ||
758 | @menu | |
759 | * Comms (EB29K):: Communications setup | |
760 | * gdb-EB29K:: EB29K cross-debugging | |
761 | * Remote Log:: Remote log | |
762 | @end menu | |
763 | ||
764 | @node Comms (EB29K) | |
765 | @subsubsection Communications setup | |
766 | ||
767 | The next step is to set up the PC's port, by doing something like this | |
768 | in DOS on the PC: | |
769 | ||
770 | @example | |
771 | C:\> MODE com1:9600,n,8,1,none | |
772 | @end example | |
773 | ||
774 | @noindent | |
775 | This example---run on an MS DOS 4.0 system---sets the PC port to 9600 | |
776 | bps, no parity, eight data bits, one stop bit, and no ``retry'' action; | |
777 | you must match the communications parameters when establishing the Unix | |
778 | end of the connection as well. | |
779 | @c FIXME: Who knows what this "no retry action" crud from the DOS manual may | |
780 | @c mean? It's optional; leave it out? ---pesch@cygnus.com, 25feb91 | |
781 | ||
782 | To give control of the PC to the Unix side of the serial line, type | |
783 | the following at the DOS console: | |
784 | ||
785 | @example | |
786 | C:\> CTTY com1 | |
787 | @end example | |
788 | ||
789 | @noindent | |
790 | (Later, if you wish to return control to the DOS console, you can use | |
791 | the command @code{CTTY con}---but you must send it over the device that | |
792 | had control, in our example over the @file{COM1} serial line). | |
793 | ||
794 | From the Unix host, use a communications program such as @code{tip} or | |
795 | @code{cu} to communicate with the PC; for example, | |
796 | ||
797 | @example | |
798 | cu -s 9600 -l /dev/ttya | |
799 | @end example | |
800 | ||
801 | @noindent | |
802 | The @code{cu} options shown specify, respectively, the linespeed and the | |
803 | serial port to use. If you use @code{tip} instead, your command line | |
804 | may look something like the following: | |
805 | ||
806 | @example | |
807 | tip -9600 /dev/ttya | |
808 | @end example | |
809 | ||
810 | @noindent | |
811 | Your system may require a different name where we show | |
812 | @file{/dev/ttya} as the argument to @code{tip}. The communications | |
813 | parameters, including which port to use, are associated with the | |
814 | @code{tip} argument in the ``remote'' descriptions file---normally the | |
815 | system table @file{/etc/remote}. | |
816 | @c FIXME: What if anything needs doing to match the "n,8,1,none" part of | |
817 | @c the DOS side's comms setup? cu can support -o (odd | |
818 | @c parity), -e (even parity)---apparently no settings for no parity or | |
819 | @c for character size. Taken from stty maybe...? John points out tip | |
820 | @c can set these as internal variables, eg ~s parity=none; man stty | |
821 | @c suggests that it *might* work to stty these options with stdin or | |
822 | @c stdout redirected... ---pesch@cygnus.com, 25feb91 | |
823 | ||
824 | @kindex EBMON | |
825 | Using the @code{tip} or @code{cu} connection, change the DOS working | |
826 | directory to the directory containing a copy of your 29K program, then | |
827 | start the PC program @code{EBMON} (an EB29K control program supplied | |
828 | with your board by AMD). You should see an initial display from | |
829 | @code{EBMON} similar to the one that follows, ending with the | |
830 | @code{EBMON} prompt @samp{#}--- | |
831 | ||
832 | @example | |
833 | C:\> G: | |
834 | ||
835 | G:\> CD \usr\joe\work29k | |
836 | ||
837 | G:\USR\JOE\WORK29K> EBMON | |
838 | Am29000 PC Coprocessor Board Monitor, version 3.0-18 | |
839 | Copyright 1990 Advanced Micro Devices, Inc. | |
840 | Written by Gibbons and Associates, Inc. | |
841 | ||
842 | Enter '?' or 'H' for help | |
843 | ||
844 | PC Coprocessor Type = EB29K | |
845 | I/O Base = 0x208 | |
846 | Memory Base = 0xd0000 | |
847 | ||
848 | Data Memory Size = 2048KB | |
849 | Available I-RAM Range = 0x8000 to 0x1fffff | |
850 | Available D-RAM Range = 0x80002000 to 0x801fffff | |
851 | ||
852 | PageSize = 0x400 | |
853 | Register Stack Size = 0x800 | |
854 | Memory Stack Size = 0x1800 | |
855 | ||
856 | CPU PRL = 0x3 | |
857 | Am29027 Available = No | |
858 | Byte Write Available = Yes | |
859 | ||
860 | # ~. | |
861 | @end example | |
862 | ||
863 | Then exit the @code{cu} or @code{tip} program (done in the example by | |
9a27b06e | 864 | typing @code{~.} at the @code{EBMON} prompt). @code{EBMON} keeps |
4af6d502 RP |
865 | running, ready for @value{GDBN} to take over. |
866 | ||
867 | For this example, we've assumed what is probably the most convenient | |
868 | way to make sure the same 29K program is on both the PC and the Unix | |
869 | system: a PC/NFS connection that establishes ``drive @code{G:}'' on the | |
870 | PC as a file system on the Unix host. If you do not have PC/NFS or | |
871 | something similar connecting the two systems, you must arrange some | |
872 | other way---perhaps floppy-disk transfer---of getting the 29K program | |
9a27b06e | 873 | from the Unix system to the PC; @value{GDBN} does @emph{not} download it over the |
4af6d502 RP |
874 | serial line. |
875 | ||
876 | @node gdb-EB29K | |
877 | @subsubsection EB29K cross-debugging | |
878 | ||
879 | Finally, @code{cd} to the directory containing an image of your 29K | |
880 | program on the Unix system, and start @value{GDBN}---specifying as argument the | |
881 | name of your 29K program: | |
882 | ||
883 | @example | |
884 | cd /usr/joe/work29k | |
885 | @value{GDBP} myfoo | |
886 | @end example | |
887 | ||
b1955f0b | 888 | @need 500 |
4af6d502 RP |
889 | Now you can use the @code{target} command: |
890 | ||
891 | @example | |
892 | target amd-eb /dev/ttya 9600 MYFOO | |
893 | @c FIXME: test above 'target amd-eb' as spelled, with caps! caps are meant to | |
894 | @c emphasize that this is the name as seen by DOS (since I think DOS is | |
895 | @c single-minded about case of letters). ---pesch@cygnus.com, 25feb91 | |
896 | @end example | |
897 | ||
898 | @noindent | |
899 | In this example, we've assumed your program is in a file called | |
900 | @file{myfoo}. Note that the filename given as the last argument to | |
901 | @code{target amd-eb} should be the name of the program as it appears to DOS. | |
902 | In our example this is simply @code{MYFOO}, but in general it can include | |
903 | a DOS path, and depending on your transfer mechanism may not resemble | |
904 | the name on the Unix side. | |
905 | ||
906 | At this point, you can set any breakpoints you wish; when you are ready | |
907 | to see your program run on the 29K board, use the @value{GDBN} command | |
908 | @code{run}. | |
909 | ||
910 | To stop debugging the remote program, use the @value{GDBN} @code{detach} | |
911 | command. | |
912 | ||
913 | To return control of the PC to its console, use @code{tip} or @code{cu} | |
914 | once again, after your @value{GDBN} session has concluded, to attach to | |
915 | @code{EBMON}. You can then type the command @code{q} to shut down | |
916 | @code{EBMON}, returning control to the DOS command-line interpreter. | |
917 | Type @code{CTTY con} to return command input to the main DOS console, | |
918 | and type @kbd{~.} to leave @code{tip} or @code{cu}. | |
919 | ||
920 | @node Remote Log | |
921 | @subsubsection Remote log | |
922 | @kindex eb.log | |
923 | @cindex log file for EB29K | |
924 | ||
925 | The @code{target amd-eb} command creates a file @file{eb.log} in the | |
926 | current working directory, to help debug problems with the connection. | |
927 | @file{eb.log} records all the output from @code{EBMON}, including echoes | |
928 | of the commands sent to it. Running @samp{tail -f} on this file in | |
929 | another window often helps to understand trouble with @code{EBMON}, or | |
930 | unexpected events on the PC side of the connection. | |
931 | ||
932 | @end ifset | |
933 | ||
934 | @ifset ST2000 | |
935 | @node ST2000 Remote | |
936 | @subsection @value{GDBN} with a Tandem ST2000 | |
937 | ||
938 | To connect your ST2000 to the host system, see the manufacturer's | |
af215b1a | 939 | manual. Once the ST2000 is physically attached, you can run: |
4af6d502 RP |
940 | |
941 | @example | |
942 | target st2000 @var{dev} @var{speed} | |
943 | @end example | |
944 | ||
945 | @noindent | |
946 | to establish it as your debugging environment. @var{dev} is normally | |
947 | the name of a serial device, such as @file{/dev/ttya}, connected to the | |
948 | ST2000 via a serial line. You can instead specify @var{dev} as a TCP | |
949 | connection (for example, to a serial line attached via a terminal | |
950 | concentrator) using the syntax @code{@var{hostname}:@var{portnumber}}. | |
951 | ||
952 | The @code{load} and @code{attach} commands are @emph{not} defined for | |
953 | this target; you must load your program into the ST2000 as you normally | |
9a27b06e | 954 | would for standalone operation. @value{GDBN} reads debugging information |
4af6d502 RP |
955 | (such as symbols) from a separate, debugging version of the program |
956 | available on your host computer. | |
957 | @c FIXME!! This is terribly vague; what little content is here is | |
958 | @c basically hearsay. | |
959 | ||
960 | @cindex ST2000 auxiliary commands | |
961 | These auxiliary @value{GDBN} commands are available to help you with the ST2000 | |
962 | environment: | |
963 | ||
964 | @table @code | |
965 | @item st2000 @var{command} | |
966 | @kindex st2000 @var{cmd} | |
967 | @cindex STDBUG commands (ST2000) | |
968 | @cindex commands to STDBUG (ST2000) | |
969 | Send a @var{command} to the STDBUG monitor. See the manufacturer's | |
970 | manual for available commands. | |
971 | ||
972 | @item connect | |
973 | @cindex connect (to STDBUG) | |
974 | Connect the controlling terminal to the STDBUG command monitor. When | |
975 | you are done interacting with STDBUG, typing either of two character | |
9a27b06e | 976 | sequences gets you back to the @value{GDBN} command prompt: |
4af6d502 RP |
977 | @kbd{@key{RET}~.} (Return, followed by tilde and period) or |
978 | @kbd{@key{RET}~@key{C-d}} (Return, followed by tilde and control-D). | |
979 | @end table | |
980 | @end ifset | |
981 | ||
982 | @ifset VXWORKS | |
983 | @node VxWorks Remote | |
984 | @subsection @value{GDBN} and VxWorks | |
985 | @cindex VxWorks | |
986 | ||
987 | @value{GDBN} enables developers to spawn and debug tasks running on networked | |
988 | VxWorks targets from a Unix host. Already-running tasks spawned from | |
989 | the VxWorks shell can also be debugged. @value{GDBN} uses code that runs on | |
6b51acad RP |
990 | both the Unix host and on the VxWorks target. The program |
991 | @code{gdb} is installed and executed on the Unix host. (It may be | |
4af6d502 RP |
992 | installed with the name @code{vxgdb}, to distinguish it from a |
993 | @value{GDBN} for debugging programs on the host itself.) | |
994 | ||
af215b1a VM |
995 | @table @code |
996 | @item VxWorks-timeout @var{args} | |
997 | @kindex vxworks-timeout | |
998 | All VxWorks-based targets now support the option @code{vxworks-timeout}. | |
999 | This option is set by the user, and @var{args} represents the number of | |
1000 | seconds @value{GDBN} waits for responses to rpc's. You might use this if | |
1001 | your VxWorks target is a slow software simulator or is on the far side | |
1002 | of a thin network line. | |
1003 | @end table | |
1004 | ||
4af6d502 RP |
1005 | The following information on connecting to VxWorks was current when |
1006 | this manual was produced; newer releases of VxWorks may use revised | |
1007 | procedures. | |
1008 | ||
4af6d502 | 1009 | @kindex INCLUDE_RDB |
ffbfe250 JK |
1010 | To use @value{GDBN} with VxWorks, you must rebuild your VxWorks kernel |
1011 | to include the remote debugging interface routines in the VxWorks | |
1012 | library @file{rdb.a}. To do this, define @code{INCLUDE_RDB} in the | |
1013 | VxWorks configuration file @file{configAll.h} and rebuild your VxWorks | |
9a27b06e | 1014 | kernel. The resulting kernel contains @file{rdb.a}, and spawns the |
ffbfe250 JK |
1015 | source debugging task @code{tRdbTask} when VxWorks is booted. For more |
1016 | information on configuring and remaking VxWorks, see the manufacturer's | |
1017 | manual. | |
4af6d502 RP |
1018 | @c VxWorks, see the @cite{VxWorks Programmer's Guide}. |
1019 | ||
ffbfe250 JK |
1020 | Once you have included @file{rdb.a} in your VxWorks system image and set |
1021 | your Unix execution search path to find @value{GDBN}, you are ready to | |
1022 | run @value{GDBN}. From your Unix host, run @code{gdb} (or @code{vxgdb}, | |
1023 | depending on your installation). | |
4af6d502 RP |
1024 | |
1025 | @value{GDBN} comes up showing the prompt: | |
1026 | ||
1027 | @example | |
1028 | (vxgdb) | |
1029 | @end example | |
1030 | ||
1031 | @menu | |
1032 | * VxWorks Connection:: Connecting to VxWorks | |
1033 | * VxWorks Download:: VxWorks download | |
1034 | * VxWorks Attach:: Running tasks | |
1035 | @end menu | |
1036 | ||
1037 | @node VxWorks Connection | |
1038 | @subsubsection Connecting to VxWorks | |
1039 | ||
1040 | The @value{GDBN} command @code{target} lets you connect to a VxWorks target on the | |
1041 | network. To connect to a target whose host name is ``@code{tt}'', type: | |
1042 | ||
1043 | @example | |
1044 | (vxgdb) target vxworks tt | |
1045 | @end example | |
1046 | ||
b1955f0b | 1047 | @need 750 |
4af6d502 RP |
1048 | @value{GDBN} displays messages like these: |
1049 | ||
1050 | @smallexample | |
1051 | Attaching remote machine across net... | |
1052 | Connected to tt. | |
1053 | @end smallexample | |
1054 | ||
b1955f0b | 1055 | @need 1000 |
4af6d502 RP |
1056 | @value{GDBN} then attempts to read the symbol tables of any object modules |
1057 | loaded into the VxWorks target since it was last booted. @value{GDBN} locates | |
1058 | these files by searching the directories listed in the command search | |
1059 | path (@pxref{Environment, ,Your program's environment}); if it fails | |
1060 | to find an object file, it displays a message such as: | |
1061 | ||
1062 | @example | |
1063 | prog.o: No such file or directory. | |
1064 | @end example | |
1065 | ||
1066 | When this happens, add the appropriate directory to the search path with | |
1067 | the @value{GDBN} command @code{path}, and execute the @code{target} | |
1068 | command again. | |
1069 | ||
1070 | @node VxWorks Download | |
1071 | @subsubsection VxWorks download | |
1072 | ||
1073 | @cindex download to VxWorks | |
1074 | If you have connected to the VxWorks target and you want to debug an | |
1075 | object that has not yet been loaded, you can use the @value{GDBN} | |
6b51acad | 1076 | @code{load} command to download a file from Unix to VxWorks |
4af6d502 RP |
1077 | incrementally. The object file given as an argument to the @code{load} |
1078 | command is actually opened twice: first by the VxWorks target in order | |
1079 | to download the code, then by @value{GDBN} in order to read the symbol | |
1080 | table. This can lead to problems if the current working directories on | |
1081 | the two systems differ. If both systems have NFS mounted the same | |
1082 | filesystems, you can avoid these problems by using absolute paths. | |
1083 | Otherwise, it is simplest to set the working directory on both systems | |
1084 | to the directory in which the object file resides, and then to reference | |
1085 | the file by its name, without any path. For instance, a program | |
1086 | @file{prog.o} may reside in @file{@var{vxpath}/vw/demo/rdb} in VxWorks | |
1087 | and in @file{@var{hostpath}/vw/demo/rdb} on the host. To load this | |
1088 | program, type this on VxWorks: | |
1089 | ||
1090 | @example | |
1091 | -> cd "@var{vxpath}/vw/demo/rdb" | |
1092 | @end example | |
af215b1a | 1093 | v |
4af6d502 RP |
1094 | Then, in @value{GDBN}, type: |
1095 | ||
1096 | @example | |
1097 | (vxgdb) cd @var{hostpath}/vw/demo/rdb | |
1098 | (vxgdb) load prog.o | |
1099 | @end example | |
1100 | ||
1101 | @value{GDBN} displays a response similar to this: | |
1102 | ||
1103 | @smallexample | |
1104 | Reading symbol data from wherever/vw/demo/rdb/prog.o... done. | |
1105 | @end smallexample | |
1106 | ||
1107 | You can also use the @code{load} command to reload an object module | |
1108 | after editing and recompiling the corresponding source file. Note that | |
9a27b06e | 1109 | this makes @value{GDBN} delete all currently-defined breakpoints, |
4af6d502 RP |
1110 | auto-displays, and convenience variables, and to clear the value |
1111 | history. (This is necessary in order to preserve the integrity of | |
1112 | debugger data structures that reference the target system's symbol | |
1113 | table.) | |
1114 | ||
1115 | @node VxWorks Attach | |
1116 | @subsubsection Running tasks | |
1117 | ||
1118 | @cindex running VxWorks tasks | |
1119 | You can also attach to an existing task using the @code{attach} command as | |
1120 | follows: | |
1121 | ||
1122 | @example | |
1123 | (vxgdb) attach @var{task} | |
1124 | @end example | |
1125 | ||
1126 | @noindent | |
1127 | where @var{task} is the VxWorks hexadecimal task ID. The task can be running | |
9a27b06e | 1128 | or suspended when you attach to it. Running tasks are suspended at |
4af6d502 RP |
1129 | the time of attachment. |
1130 | @end ifset | |
1131 | ||
1132 | @ifset H8 | |
1133 | @node Hitachi Remote | |
2ded09f5 | 1134 | @subsection @value{GDBN} and Hitachi microprocessors |
4af6d502 RP |
1135 | @value{GDBN} needs to know these things to talk to your |
1136 | Hitachi SH, H8/300, or H8/500: | |
1137 | ||
1138 | @enumerate | |
1139 | @item | |
1140 | that you want to use @samp{target hms}, the remote debugging interface | |
2ded09f5 RP |
1141 | for Hitachi microprocessors, or @samp{target e7000}, the in-circuit |
1142 | emulator for the Hitachi SH and the Hitachi 300H. (@samp{target hms} is | |
1143 | the default when GDB is configured specifically for the Hitachi SH, | |
1144 | H8/300, or H8/500.) | |
4af6d502 RP |
1145 | |
1146 | @item | |
1147 | what serial device connects your host to your Hitachi board (the first | |
2ded09f5 | 1148 | serial device available on your host is the default). |
4af6d502 | 1149 | |
2ded09f5 RP |
1150 | @ifclear H8EXCLUSIVE |
1151 | @c this is only for Unix hosts, not of interest to Hitachi | |
4af6d502 RP |
1152 | @item |
1153 | what speed to use over the serial device. | |
2ded09f5 | 1154 | @end ifclear |
4af6d502 RP |
1155 | @end enumerate |
1156 | ||
2ded09f5 | 1157 | @menu |
009ed681 RP |
1158 | * Hitachi Boards:: Connecting to Hitachi boards. |
1159 | * Hitachi ICE:: Using the E7000 In-Circuit Emulator. | |
1160 | * Hitachi Special:: Special @value{GDBN} commands for Hitachi micros. | |
2ded09f5 RP |
1161 | @end menu |
1162 | ||
1163 | @node Hitachi Boards | |
1164 | @subsubsection Connecting to Hitachi boards | |
1165 | ||
4af6d502 RP |
1166 | @ifclear H8EXCLUSIVE |
1167 | @c only for Unix hosts | |
1168 | @kindex device | |
1169 | @cindex serial device, Hitachi micros | |
1170 | Use the special @code{@value{GDBP}} command @samp{device @var{port}} if you | |
1171 | need to explicitly set the serial device. The default @var{port} is the | |
1172 | first available port on your host. This is only necessary on Unix | |
1173 | hosts, where it is typically something like @file{/dev/ttya}. | |
1174 | ||
1175 | @kindex speed | |
1176 | @cindex serial line speed, Hitachi micros | |
1177 | @code{@value{GDBP}} has another special command to set the communications | |
1178 | speed: @samp{speed @var{bps}}. This command also is only used from Unix | |
1179 | hosts; on DOS hosts, set the line speed as usual from outside GDB with | |
1180 | the DOS @kbd{mode} command (for instance, @w{@samp{mode | |
1181 | com2:9600,n,8,1,p}} for a 9600 bps connection). | |
1182 | ||
1183 | The @samp{device} and @samp{speed} commands are available only when you | |
1184 | use a Unix host to debug your Hitachi microprocessor programs. If you | |
1185 | use a DOS host, | |
1186 | @end ifclear | |
1187 | @value{GDBN} depends on an auxiliary terminate-and-stay-resident program | |
1188 | called @code{asynctsr} to communicate with the development board | |
1189 | through a PC serial port. You must also use the DOS @code{mode} command | |
1190 | to set up the serial port on the DOS side. | |
1191 | ||
1192 | @ifset DOSHOST | |
1193 | The following sample session illustrates the steps needed to start a | |
1194 | program under @value{GDBN} control on an H8/300. The example uses a | |
1195 | sample H8/300 program called @file{t.x}. The procedure is the same for | |
1196 | the Hitachi SH and the H8/500. | |
1197 | ||
1198 | First hook up your development board. In this example, we use a | |
1199 | board attached to serial port @code{COM2}; if you use a different serial | |
1200 | port, substitute its name in the argument of the @code{mode} command. | |
1201 | When you call @code{asynctsr}, the auxiliary comms program used by the | |
1202 | degugger, you give it just the numeric part of the serial port's name; | |
1203 | for example, @samp{asyncstr 2} below runs @code{asyncstr} on | |
1204 | @code{COM2}. | |
1205 | ||
1206 | @example | |
e3a58c92 JO |
1207 | C:\H8300\TEST> asynctsr 2 |
1208 | C:\H8300\TEST> mode com2:9600,n,8,1,p | |
4af6d502 RP |
1209 | |
1210 | Resident portion of MODE loaded | |
1211 | ||
1212 | COM2: 9600, n, 8, 1, p | |
1213 | ||
4af6d502 RP |
1214 | @end example |
1215 | ||
1216 | @quotation | |
1217 | @emph{Warning:} We have noticed a bug in PC-NFS that conflicts with | |
1218 | @code{asynctsr}. If you also run PC-NFS on your DOS host, you may need to | |
1219 | disable it, or even boot without it, to use @code{asynctsr} to control | |
1220 | your development board. | |
1221 | @end quotation | |
1222 | ||
1223 | @kindex target hms | |
1224 | Now that serial communications are set up, and the development board is | |
1225 | connected, you can start up @value{GDBN}. Call @code{@value{GDBP}} with | |
1226 | the name of your program as the argument. @code{@value{GDBP}} prompts | |
1227 | you, as usual, with the prompt @samp{(@value{GDBP})}. Use two special | |
1228 | commands to begin your debugging session: @samp{target hms} to specify | |
1229 | cross-debugging to the Hitachi board, and the @code{load} command to | |
1230 | download your program to the board. @code{load} displays the names of | |
1231 | the program's sections, and a @samp{*} for each 2K of data downloaded. | |
1232 | (If you want to refresh @value{GDBN} data on symbols or on the | |
1233 | executable file without downloading, use the @value{GDBN} commands | |
1234 | @code{file} or @code{symbol-file}. These commands, and @code{load} | |
1235 | itself, are described in @ref{Files,,Commands to specify files}.) | |
1236 | ||
1237 | @smallexample | |
1238 | (eg-C:\H8300\TEST) @value{GDBP} t.x | |
1239 | GDB is free software and you are welcome to distribute copies | |
1240 | of it under certain conditions; type "show copying" to see | |
1241 | the conditions. | |
1242 | There is absolutely no warranty for GDB; type "show warranty" | |
1243 | for details. | |
1244 | GDB @value{GDBVN}, Copyright 1992 Free Software Foundation, Inc... | |
1245 | (gdb) target hms | |
1246 | Connected to remote H8/300 HMS system. | |
1247 | (gdb) load t.x | |
1248 | .text : 0x8000 .. 0xabde *********** | |
1249 | .data : 0xabde .. 0xad30 * | |
1250 | .stack : 0xf000 .. 0xf014 * | |
1251 | @end smallexample | |
1252 | ||
1253 | At this point, you're ready to run or debug your program. From here on, | |
1254 | you can use all the usual @value{GDBN} commands. The @code{break} command | |
1255 | sets breakpoints; the @code{run} command starts your program; | |
1256 | @code{print} or @code{x} display data; the @code{continue} command | |
1257 | resumes execution after stopping at a breakpoint. You can use the | |
1258 | @code{help} command at any time to find out more about @value{GDBN} commands. | |
1259 | ||
1260 | Remember, however, that @emph{operating system} facilities aren't | |
1261 | available on your development board; for example, if your program hangs, | |
1262 | you can't send an interrupt---but you can press the @sc{reset} switch! | |
1263 | ||
1264 | Use the @sc{reset} button on the development board | |
1265 | @itemize @bullet | |
1266 | @item | |
1267 | to interrupt your program (don't use @kbd{ctl-C} on the DOS host---it has | |
1268 | no way to pass an interrupt signal to the development board); and | |
1269 | ||
1270 | @item | |
1271 | to return to the @value{GDBN} command prompt after your program finishes | |
1272 | normally. The communications protocol provides no other way for @value{GDBN} | |
1273 | to detect program completion. | |
1274 | @end itemize | |
1275 | ||
9a27b06e | 1276 | In either case, @value{GDBN} sees the effect of a @sc{reset} on the |
4af6d502 | 1277 | development board as a ``normal exit'' of your program. |
009ed681 | 1278 | @end ifset |
2ded09f5 RP |
1279 | |
1280 | @node Hitachi ICE | |
1281 | @subsubsection Using the E7000 in-circuit emulator | |
1282 | ||
1283 | @kindex target e7000 | |
1284 | You can use the E7000 in-circuit emulator to develop code for either the | |
1285 | Hitachi SH or the H8/300H. Use one of these forms of the @samp{target | |
1286 | e7000} command to connect @value{GDBN} to your E7000: | |
1287 | ||
1288 | @table @code | |
1289 | @item target e7000 @var{port} @var{speed} | |
1290 | Use this form if your E7000 is connected to a serial port. The | |
1291 | @var{port} argument identifies what serial port to use (for example, | |
1292 | @samp{com2}). The third argument is the line speed in bits per second | |
1293 | (for example, @samp{9600}). | |
1294 | ||
1295 | @item target e7000 @var{hostname} | |
1296 | If your E7000 is installed as a host on a TCP/IP network, you can just | |
1297 | specify its hostname; @value{GDBN} uses @code{telnet} to connect. | |
1298 | @end table | |
1299 | ||
1300 | @node Hitachi Special | |
1301 | @subsubsection Special @value{GDBN} commands for Hitachi micros | |
1302 | ||
1303 | Some @value{GDBN} commands are available only on the H8/300 or the | |
1304 | H8/500 configurations: | |
1305 | ||
1306 | @table @code | |
1307 | @kindex set machine | |
1308 | @kindex show machine | |
1309 | @item set machine h8300 | |
1310 | @itemx set machine h8300h | |
1311 | Condition @value{GDBN} for one of the two variants of the H8/300 | |
1312 | architecture with @samp{set machine}. You can use @samp{show machine} | |
1313 | to check which variant is currently in effect. | |
1314 | ||
1315 | @kindex set memory @var{mod} | |
1316 | @cindex memory models, H8/500 | |
1317 | @item set memory @var{mod} | |
1318 | @itemx show memory | |
1319 | Specify which H8/500 memory model (@var{mod}) you are using with | |
1320 | @samp{set memory}; check which memory model is in effect with @samp{show | |
1321 | memory}. The accepted values for @var{mod} are @code{small}, | |
1322 | @code{big}, @code{medium}, and @code{compact}. | |
1323 | @end table | |
1324 | ||
4af6d502 RP |
1325 | @end ifset |
1326 | ||
1327 | @ifset MIPS | |
1328 | @node MIPS Remote | |
1329 | @subsection @value{GDBN} and remote MIPS boards | |
1330 | ||
1331 | @cindex MIPS boards | |
1332 | @value{GDBN} can use the MIPS remote debugging protocol to talk to a | |
1333 | MIPS board attached to a serial line. This is available when | |
1334 | you configure @value{GDBN} with @samp{--target=mips-idt-ecoff}. | |
1335 | ||
b1955f0b | 1336 | @need 1000 |
22b5dba5 RP |
1337 | Use these @value{GDBN} commands to specify the connection to your target board: |
1338 | ||
1339 | @table @code | |
1340 | @item target mips @var{port} | |
4af6d502 RP |
1341 | @kindex target mips @var{port} |
1342 | To run a program on the board, start up @code{@value{GDBP}} with the | |
1343 | name of your program as the argument. To connect to the board, use the | |
1344 | command @samp{target mips @var{port}}, where @var{port} is the name of | |
1345 | the serial port connected to the board. If the program has not already | |
1346 | been downloaded to the board, you may use the @code{load} command to | |
1347 | download it. You can then use all the usual @value{GDBN} commands. | |
1348 | ||
22b5dba5 RP |
1349 | For example, this sequence connects to the target board through a serial |
1350 | port, and loads and runs a program called @var{prog} through the | |
1351 | debugger: | |
1352 | ||
1353 | @example | |
1354 | host$ @value{GDBP} @var{prog} | |
1355 | GDB is free software and @dots{} | |
1356 | (gdb) target mips /dev/ttyb | |
1357 | (gdb) load @var{prog} | |
1358 | (gdb) run | |
1359 | @end example | |
1360 | ||
1361 | @item target mips @var{hostname}:@var{portnumber} | |
1362 | On some @value{GDBN} host configurations, you can specify a TCP | |
1363 | connection (for instance, to a serial line managed by a terminal | |
1364 | concentrator) instead of a serial port, using the syntax | |
1365 | @samp{@var{hostname}:@var{portnumber}}. | |
1366 | @end table | |
1367 | ||
1368 | @noindent | |
1369 | @value{GDBN} also supports these special commands for MIPS targets: | |
4af6d502 | 1370 | |
22b5dba5 | 1371 | @table @code |
af215b1a VM |
1372 | @item set processor @var{args} |
1373 | @itemx show processor | |
1374 | @kindex set processor @var{args} | |
1375 | @kindex show processor | |
1376 | Use the @code{set processor} command to set the type of MIPS | |
1377 | processor when you want to access processor-type-specific registers. | |
1378 | For example, @code{set processor @var{r3041}} tells @value{GDBN} | |
1379 | to use the CPO registers appropriate for the 3041 chip. | |
1380 | Use the @code{show processor} command to see what MIPS processor @value{GDBN} | |
1381 | is using. Use the @code{info reg} command to see what registers | |
1382 | @value{GDBN} is using. | |
1383 | ||
89dd4786 ILT |
1384 | @item set mipsfpu double |
1385 | @itemx set mipsfpu single | |
1386 | @itemx set mipsfpu none | |
22b5dba5 | 1387 | @itemx show mipsfpu |
89dd4786 | 1388 | @kindex set mipsfpu |
22b5dba5 RP |
1389 | @kindex show mipsfpu |
1390 | @cindex MIPS remote floating point | |
1391 | @cindex floating point, MIPS remote | |
1392 | If your target board does not support the MIPS floating point | |
89dd4786 | 1393 | coprocessor, you should use the command @samp{set mipsfpu none} (if you |
22b5dba5 RP |
1394 | need this, you may wish to put the command in your @value{GDBINIT} |
1395 | file). This tells @value{GDBN} how to find the return value of | |
1396 | functions which return floating point values. It also allows | |
1397 | @value{GDBN} to avoid saving the floating point registers when calling | |
89dd4786 ILT |
1398 | functions on the board. If you are using a floating point coprocessor |
1399 | with only single precision floating point support, as on the @sc{r4650} | |
1400 | processor, use the command @samp{set mipsfpu single}. The default | |
1401 | double precision floating point coprocessor may be selected using | |
1402 | @samp{set mipsfpu double}. | |
1403 | ||
1404 | In previous versions the only choices were double precision or no | |
1405 | floating point, so @samp{set mipsfpu on} will select double precision | |
1406 | and @samp{set mipsfpu off} will select no floating point. | |
1407 | ||
1408 | As usual, you can inquire about the @code{mipsfpu} variable with | |
1409 | @samp{show mipsfpu}. | |
22b5dba5 RP |
1410 | |
1411 | @item set remotedebug @var{n} | |
1412 | @itemx show remotedebug | |
1413 | @kindex set remotedebug | |
1414 | @kindex show remotedebug | |
4af6d502 | 1415 | @cindex @code{remotedebug}, MIPS protocol |
22b5dba5 | 1416 | @cindex MIPS @code{remotedebug} protocol |
4af6d502 RP |
1417 | @c FIXME! For this to be useful, you must know something about the MIPS |
1418 | @c FIXME...protocol. Where is it described? | |
1419 | You can see some debugging information about communications with the board | |
22b5dba5 RP |
1420 | by setting the @code{remotedebug} variable. If you set it to @code{1} using |
1421 | @samp{set remotedebug 1}, every packet is displayed. If you set it | |
1422 | to @code{2}, every character is displayed. You can check the current value | |
4af6d502 RP |
1423 | at any time with the command @samp{show remotedebug}. |
1424 | ||
22b5dba5 RP |
1425 | @item set timeout @var{seconds} |
1426 | @itemx set retransmit-timeout @var{seconds} | |
1427 | @itemx show timeout | |
1428 | @itemx show retransmit-timeout | |
4af6d502 RP |
1429 | @cindex @code{timeout}, MIPS protocol |
1430 | @cindex @code{retransmit-timeout}, MIPS protocol | |
f21c5362 RP |
1431 | @kindex set timeout |
1432 | @kindex show timeout | |
1433 | @kindex set retransmit-timeout | |
1434 | @kindex show retransmit-timeout | |
1435 | You can control the timeout used while waiting for a packet, in the MIPS | |
1436 | remote protocol, with the @code{set timeout @var{seconds}} command. The | |
1437 | default is 5 seconds. Similarly, you can control the timeout used while | |
1438 | waiting for an acknowledgement of a packet with the @code{set | |
1439 | retransmit-timeout @var{seconds}} command. The default is 3 seconds. | |
1440 | You can inspect both values with @code{show timeout} and @code{show | |
1441 | retransmit-timeout}. (These commands are @emph{only} available when | |
1442 | @value{GDBN} is configured for @samp{--target=mips-idt-ecoff}.) | |
5940bfd9 JK |
1443 | |
1444 | The timeout set by @code{set timeout} does not apply when @value{GDBN} | |
1445 | is waiting for your program to stop. In that case, @value{GDBN} waits | |
1446 | forever because it has no way of knowing how long the program is going | |
1447 | to run before stopping. | |
22b5dba5 | 1448 | @end table |
4af6d502 RP |
1449 | @end ifset |
1450 | ||
1451 | @ifset SIMS | |
1452 | @node Simulator | |
1453 | @subsection Simulated CPU target | |
1454 | ||
1455 | @ifset GENERIC | |
1456 | @cindex simulator | |
1457 | @cindex simulator, Z8000 | |
1458 | @cindex Z8000 simulator | |
1459 | @cindex simulator, H8/300 or H8/500 | |
1460 | @cindex H8/300 or H8/500 simulator | |
1461 | @cindex simulator, Hitachi SH | |
1462 | @cindex Hitachi SH simulator | |
1463 | @cindex CPU simulator | |
1464 | For some configurations, @value{GDBN} includes a CPU simulator that you | |
1465 | can use instead of a hardware CPU to debug your programs. Currently, | |
1466 | a simulator is available when @value{GDBN} is configured to debug Zilog | |
1467 | Z8000 or Hitachi microprocessor targets. | |
1468 | @end ifset | |
1469 | ||
1470 | @ifclear GENERIC | |
1471 | @ifset H8 | |
1472 | @cindex simulator, H8/300 or H8/500 | |
1473 | @cindex Hitachi H8/300 or H8/500 simulator | |
1474 | @cindex simulator, Hitachi SH | |
1475 | @cindex Hitachi SH simulator | |
1476 | When configured for debugging Hitachi microprocessor targets, | |
1477 | @value{GDBN} includes a CPU simulator for the target chip (a Hitachi SH, | |
1478 | H8/300, or H8/500). | |
1479 | @end ifset | |
1480 | ||
1481 | @ifset Z8K | |
1482 | @cindex simulator, Z8000 | |
1483 | @cindex Zilog Z8000 simulator | |
1484 | When configured for debugging Zilog Z8000 targets, @value{GDBN} includes | |
1485 | a Z8000 simulator. | |
1486 | @end ifset | |
1487 | @end ifclear | |
1488 | ||
1489 | @ifset Z8K | |
1490 | For the Z8000 family, @samp{target sim} simulates either the Z8002 (the | |
1491 | unsegmented variant of the Z8000 architecture) or the Z8001 (the | |
1492 | segmented variant). The simulator recognizes which architecture is | |
1493 | appropriate by inspecting the object code. | |
1494 | @end ifset | |
1495 | ||
1496 | @table @code | |
1497 | @item target sim | |
1498 | @kindex sim | |
1499 | @kindex target sim | |
1500 | Debug programs on a simulated CPU | |
1501 | @ifset GENERIC | |
1502 | (which CPU depends on the @value{GDBN} configuration) | |
1503 | @end ifset | |
1504 | @end table | |
1505 | ||
1506 | @noindent | |
1507 | After specifying this target, you can debug programs for the simulated | |
1508 | CPU in the same style as programs for your host computer; use the | |
1509 | @code{file} command to load a new program image, the @code{run} command | |
1510 | to run your program, and so on. | |
1511 | ||
1512 | As well as making available all the usual machine registers (see | |
1513 | @code{info reg}), this debugging target provides three additional items | |
1514 | of information as specially named registers: | |
1515 | ||
1516 | @table @code | |
1517 | @item cycles | |
1518 | Counts clock-ticks in the simulator. | |
1519 | ||
1520 | @item insts | |
1521 | Counts instructions run in the simulator. | |
1522 | ||
1523 | @item time | |
1524 | Execution time in 60ths of a second. | |
1525 | @end table | |
1526 | ||
1527 | You can refer to these values in @value{GDBN} expressions with the usual | |
1528 | conventions; for example, @w{@samp{b fputc if $cycles>5000}} sets a | |
9a27b06e | 1529 | conditional breakpoint that suspends only after at least 5000 |
4af6d502 RP |
1530 | simulated clock ticks. |
1531 | @end ifset |