| 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 | |
| 5 | @node Remote Serial |
| 6 | @subsection The @value{GDBN} remote serial protocol |
| 7 | |
| 8 | @cindex remote serial debugging, overview |
| 9 | To debug a program running on another machine (the debugging |
| 10 | @dfn{target} machine), you must first arrange for all the usual |
| 11 | prerequisites for the program to run by itself. For example, for a C |
| 12 | program, you need: |
| 13 | |
| 14 | @enumerate |
| 15 | @item |
| 16 | A startup routine to set up the C runtime environment; these usually |
| 17 | have a name like @file{crt0}. The startup routine may be supplied by |
| 18 | your hardware supplier, or you may have to write your own. |
| 19 | |
| 20 | @item |
| 21 | You probably need a C subroutine library to support your program's |
| 22 | subroutine calls, notably managing input and output. |
| 23 | |
| 24 | @item |
| 25 | A way of getting your program to the other machine---for example, a |
| 26 | download program. These are often supplied by the hardware |
| 27 | manufacturer, but you may have to write your own from hardware |
| 28 | documentation. |
| 29 | @end enumerate |
| 30 | |
| 31 | The next step is to arrange for your program to use a serial port to |
| 32 | communicate with the machine where @value{GDBN} is running (the @dfn{host} |
| 33 | machine). In general terms, the scheme looks like this: |
| 34 | |
| 35 | @table @emph |
| 36 | @item On the host, |
| 37 | @value{GDBN} already understands how to use this protocol; when everything |
| 38 | else is set up, you can simply use the @samp{target remote} command |
| 39 | (@pxref{Targets,,Specifying a Debugging Target}). |
| 40 | |
| 41 | @item On the target, |
| 42 | you must link with your program a few special-purpose subroutines that |
| 43 | implement the @value{GDBN} remote serial protocol. The file containing these |
| 44 | subroutines is called a @dfn{debugging stub}. |
| 45 | |
| 46 | On certain remote targets, you can use an auxiliary program |
| 47 | @code{gdbserver} instead of linking a stub into your program. |
| 48 | @xref{Server,,Using the @code{gdbserver} program}, for details. |
| 49 | @end table |
| 50 | |
| 51 | The debugging stub is specific to the architecture of the remote |
| 52 | machine; for example, use @file{sparc-stub.c} to debug programs on |
| 53 | @sc{sparc} boards. |
| 54 | |
| 55 | @cindex remote serial stub list |
| 56 | These working remote stubs are distributed with @value{GDBN}: |
| 57 | |
| 58 | @table @code |
| 59 | |
| 60 | @item i386-stub.c |
| 61 | @kindex i386-stub.c |
| 62 | @cindex Intel |
| 63 | @cindex i386 |
| 64 | For Intel 386 and compatible architectures. |
| 65 | |
| 66 | @item m68k-stub.c |
| 67 | @kindex m68k-stub.c |
| 68 | @cindex Motorola 680x0 |
| 69 | @cindex m680x0 |
| 70 | For Motorola 680x0 architectures. |
| 71 | |
| 72 | @item sh-stub.c |
| 73 | @kindex sh-stub.c |
| 74 | @cindex Hitachi |
| 75 | @cindex SH |
| 76 | For Hitachi SH architectures. |
| 77 | |
| 78 | @item sparc-stub.c |
| 79 | @kindex sparc-stub.c |
| 80 | @cindex Sparc |
| 81 | For @sc{sparc} architectures. |
| 82 | |
| 83 | @item sparcl-stub.c |
| 84 | @kindex sparcl-stub.c |
| 85 | @cindex Fujitsu |
| 86 | @cindex SparcLite |
| 87 | For Fujitsu @sc{sparclite} architectures. |
| 88 | |
| 89 | @end table |
| 90 | |
| 91 | The @file{README} file in the @value{GDBN} distribution may list other |
| 92 | recently added stubs. |
| 93 | |
| 94 | @menu |
| 95 | * Stub Contents:: What the stub can do for you |
| 96 | * Bootstrapping:: What you must do for the stub |
| 97 | * Debug Session:: Putting it all together |
| 98 | * Protocol:: Outline of the communication protocol |
| 99 | * Server:: Using the `gdbserver' program |
| 100 | * NetWare:: Using the `gdbserve.nlm' program |
| 101 | @end menu |
| 102 | |
| 103 | @node Stub Contents |
| 104 | @subsubsection What the stub can do for you |
| 105 | |
| 106 | @cindex remote serial stub |
| 107 | The debugging stub for your architecture supplies these three |
| 108 | subroutines: |
| 109 | |
| 110 | @table @code |
| 111 | @item set_debug_traps |
| 112 | @kindex set_debug_traps |
| 113 | @cindex remote serial stub, initialization |
| 114 | This routine arranges for @code{handle_exception} to run when your |
| 115 | program stops. You must call this subroutine explicitly near the |
| 116 | beginning of your program. |
| 117 | |
| 118 | @item handle_exception |
| 119 | @kindex handle_exception |
| 120 | @cindex remote serial stub, main routine |
| 121 | This is the central workhorse, but your program never calls it |
| 122 | explicitly---the setup code arranges for @code{handle_exception} to |
| 123 | run when a trap is triggered. |
| 124 | |
| 125 | @code{handle_exception} takes control when your program stops during |
| 126 | execution (for example, on a breakpoint), and mediates communications |
| 127 | with @value{GDBN} on the host machine. This is where the communications |
| 128 | protocol is implemented; @code{handle_exception} acts as the @value{GDBN} |
| 129 | representative on the target machine; it begins by sending summary |
| 130 | information on the state of your program, then continues to execute, |
| 131 | retrieving and transmitting any information @value{GDBN} needs, until you |
| 132 | execute a @value{GDBN} command that makes your program resume; at that point, |
| 133 | @code{handle_exception} returns control to your own code on the target |
| 134 | machine. |
| 135 | |
| 136 | @item breakpoint |
| 137 | @cindex @code{breakpoint} subroutine, remote |
| 138 | Use this auxiliary subroutine to make your program contain a |
| 139 | breakpoint. Depending on the particular situation, this may be the only |
| 140 | way for @value{GDBN} to get control. For instance, if your target |
| 141 | machine has some sort of interrupt button, you won't need to call this; |
| 142 | pressing the interrupt button transfers control to |
| 143 | @code{handle_exception}---in effect, to @value{GDBN}. On some machines, |
| 144 | simply receiving characters on the serial port may also trigger a trap; |
| 145 | again, in that situation, you don't need to call @code{breakpoint} from |
| 146 | your own program---simply running @samp{target remote} from the host |
| 147 | @value{GDBN} session gets control. |
| 148 | |
| 149 | Call @code{breakpoint} if none of these is true, or if you simply want |
| 150 | to make certain your program stops at a predetermined point for the |
| 151 | start of your debugging session. |
| 152 | @end table |
| 153 | |
| 154 | @node Bootstrapping |
| 155 | @subsubsection What you must do for the stub |
| 156 | |
| 157 | @cindex remote stub, support routines |
| 158 | The debugging stubs that come with @value{GDBN} are set up for a particular |
| 159 | chip architecture, but they have no information about the rest of your |
| 160 | debugging target machine. |
| 161 | |
| 162 | First of all you need to tell the stub how to communicate with the |
| 163 | serial port. |
| 164 | |
| 165 | @table @code |
| 166 | @item int getDebugChar() |
| 167 | @kindex getDebugChar |
| 168 | Write this subroutine to read a single character from the serial port. |
| 169 | It may be identical to @code{getchar} for your target system; a |
| 170 | different name is used to allow you to distinguish the two if you wish. |
| 171 | |
| 172 | @item void putDebugChar(int) |
| 173 | @kindex putDebugChar |
| 174 | Write this subroutine to write a single character to the serial port. |
| 175 | It may be identical to @code{putchar} for your target system; a |
| 176 | different name is used to allow you to distinguish the two if you wish. |
| 177 | @end table |
| 178 | |
| 179 | @cindex control C, and remote debugging |
| 180 | @cindex interrupting remote targets |
| 181 | If you want @value{GDBN} to be able to stop your program while it is |
| 182 | running, you need to use an interrupt-driven serial driver, and arrange |
| 183 | for it to stop when it receives a @code{^C} (@samp{\003}, the control-C |
| 184 | character). That is the character which @value{GDBN} uses to tell the |
| 185 | remote system to stop. |
| 186 | |
| 187 | Getting the debugging target to return the proper status to @value{GDBN} |
| 188 | probably requires changes to the standard stub; one quick and dirty way |
| 189 | is to just execute a breakpoint instruction (the ``dirty'' part is that |
| 190 | @value{GDBN} reports a @code{SIGTRAP} instead of a @code{SIGINT}). |
| 191 | |
| 192 | Other routines you need to supply are: |
| 193 | |
| 194 | @table @code |
| 195 | @item void exceptionHandler (int @var{exception_number}, void *@var{exception_address}) |
| 196 | @kindex exceptionHandler |
| 197 | Write this function to install @var{exception_address} in the exception |
| 198 | handling tables. You need to do this because the stub does not have any |
| 199 | way of knowing what the exception handling tables on your target system |
| 200 | are like (for example, the processor's table might be in @sc{rom}, |
| 201 | containing entries which point to a table in @sc{ram}). |
| 202 | @var{exception_number} is the exception number which should be changed; |
| 203 | its meaning is architecture-dependent (for example, different numbers |
| 204 | might represent divide by zero, misaligned access, etc). When this |
| 205 | exception occurs, control should be transferred directly to |
| 206 | @var{exception_address}, and the processor state (stack, registers, |
| 207 | and so on) should be just as it is when a processor exception occurs. So if |
| 208 | you want to use a jump instruction to reach @var{exception_address}, it |
| 209 | should be a simple jump, not a jump to subroutine. |
| 210 | |
| 211 | For the 386, @var{exception_address} should be installed as an interrupt |
| 212 | gate so that interrupts are masked while the handler runs. The gate |
| 213 | should be at privilege level 0 (the most privileged level). The |
| 214 | @sc{sparc} and 68k stubs are able to mask interrupts themselves without |
| 215 | help from @code{exceptionHandler}. |
| 216 | |
| 217 | @item void flush_i_cache() |
| 218 | @kindex flush_i_cache |
| 219 | (sparc and sparclite only) Write this subroutine to flush the |
| 220 | instruction cache, if any, on your target machine. If there is no |
| 221 | instruction cache, this subroutine may be a no-op. |
| 222 | |
| 223 | On target machines that have instruction caches, @value{GDBN} requires this |
| 224 | function to make certain that the state of your program is stable. |
| 225 | @end table |
| 226 | |
| 227 | @noindent |
| 228 | You must also make sure this library routine is available: |
| 229 | |
| 230 | @table @code |
| 231 | @item void *memset(void *, int, int) |
| 232 | @kindex memset |
| 233 | This is the standard library function @code{memset} that sets an area of |
| 234 | memory to a known value. If you have one of the free versions of |
| 235 | @code{libc.a}, @code{memset} can be found there; otherwise, you must |
| 236 | either obtain it from your hardware manufacturer, or write your own. |
| 237 | @end table |
| 238 | |
| 239 | If you do not use the GNU C compiler, you may need other standard |
| 240 | library subroutines as well; this varies from one stub to another, |
| 241 | but in general the stubs are likely to use any of the common library |
| 242 | subroutines which @code{gcc} generates as inline code. |
| 243 | |
| 244 | |
| 245 | @node Debug Session |
| 246 | @subsubsection Putting it all together |
| 247 | |
| 248 | @cindex remote serial debugging summary |
| 249 | In summary, when your program is ready to debug, you must follow these |
| 250 | steps. |
| 251 | |
| 252 | @enumerate |
| 253 | @item |
| 254 | Make sure you have the supporting low-level routines |
| 255 | (@pxref{Bootstrapping,,What you must do for the stub}): |
| 256 | @display |
| 257 | @code{getDebugChar}, @code{putDebugChar}, |
| 258 | @code{flush_i_cache}, @code{memset}, @code{exceptionHandler}. |
| 259 | @end display |
| 260 | |
| 261 | @item |
| 262 | Insert these lines near the top of your program: |
| 263 | |
| 264 | @example |
| 265 | set_debug_traps(); |
| 266 | breakpoint(); |
| 267 | @end example |
| 268 | |
| 269 | @item |
| 270 | For the 680x0 stub only, you need to provide a variable called |
| 271 | @code{exceptionHook}. Normally you just use: |
| 272 | |
| 273 | @example |
| 274 | void (*exceptionHook)() = 0; |
| 275 | @end example |
| 276 | |
| 277 | but if before calling @code{set_debug_traps}, you set it to point to a |
| 278 | function in your program, that function is called when |
| 279 | @code{@value{GDBN}} continues after stopping on a trap (for example, bus |
| 280 | error). The function indicated by @code{exceptionHook} is called with |
| 281 | one parameter: an @code{int} which is the exception number. |
| 282 | |
| 283 | @item |
| 284 | Compile and link together: your program, the @value{GDBN} debugging stub for |
| 285 | your target architecture, and the supporting subroutines. |
| 286 | |
| 287 | @item |
| 288 | Make sure you have a serial connection between your target machine and |
| 289 | the @value{GDBN} host, and identify the serial port on the host. |
| 290 | |
| 291 | @item |
| 292 | @c The "remote" target now provides a `load' command, so we should |
| 293 | @c document that. FIXME. |
| 294 | Download your program to your target machine (or get it there by |
| 295 | whatever means the manufacturer provides), and start it. |
| 296 | |
| 297 | @item |
| 298 | To start remote debugging, run @value{GDBN} on the host machine, and specify |
| 299 | as an executable file the program that is running in the remote machine. |
| 300 | This tells @value{GDBN} how to find your program's symbols and the contents |
| 301 | of its pure text. |
| 302 | |
| 303 | @cindex serial line, @code{target remote} |
| 304 | Then establish communication using the @code{target remote} command. |
| 305 | Its argument specifies how to communicate with the target |
| 306 | machine---either via a devicename attached to a direct serial line, or a |
| 307 | TCP port (usually to a terminal server which in turn has a serial line |
| 308 | to the target). For example, to use a serial line connected to the |
| 309 | device named @file{/dev/ttyb}: |
| 310 | |
| 311 | @example |
| 312 | target remote /dev/ttyb |
| 313 | @end example |
| 314 | |
| 315 | @cindex TCP port, @code{target remote} |
| 316 | To use a TCP connection, use an argument of the form |
| 317 | @code{@var{host}:port}. For example, to connect to port 2828 on a |
| 318 | terminal server named @code{manyfarms}: |
| 319 | |
| 320 | @example |
| 321 | target remote manyfarms:2828 |
| 322 | @end example |
| 323 | @end enumerate |
| 324 | |
| 325 | Now you can use all the usual commands to examine and change data and to |
| 326 | step and continue the remote program. |
| 327 | |
| 328 | To resume the remote program and stop debugging it, use the @code{detach} |
| 329 | command. |
| 330 | |
| 331 | @cindex interrupting remote programs |
| 332 | @cindex remote programs, interrupting |
| 333 | Whenever @value{GDBN} is waiting for the remote program, if you type the |
| 334 | interrupt character (often @key{C-C}), @value{GDBN} attempts to stop the |
| 335 | program. This may or may not succeed, depending in part on the hardware |
| 336 | and the serial drivers the remote system uses. If you type the |
| 337 | interrupt character once again, @value{GDBN} displays this prompt: |
| 338 | |
| 339 | @example |
| 340 | Interrupted while waiting for the program. |
| 341 | Give up (and stop debugging it)? (y or n) |
| 342 | @end example |
| 343 | |
| 344 | If you type @kbd{y}, @value{GDBN} abandons the remote debugging session. |
| 345 | (If you decide you want to try again later, you can use @samp{target |
| 346 | remote} again to connect once more.) If you type @kbd{n}, @value{GDBN} |
| 347 | goes back to waiting. |
| 348 | |
| 349 | @node Protocol |
| 350 | @subsubsection Communication protocol |
| 351 | |
| 352 | @cindex debugging stub, example |
| 353 | @cindex remote stub, example |
| 354 | @cindex stub example, remote debugging |
| 355 | The stub files provided with @value{GDBN} implement the target side of the |
| 356 | communication protocol, and the @value{GDBN} side is implemented in the |
| 357 | @value{GDBN} source file @file{remote.c}. Normally, you can simply allow |
| 358 | these subroutines to communicate, and ignore the details. (If you're |
| 359 | implementing your own stub file, you can still ignore the details: start |
| 360 | with one of the existing stub files. @file{sparc-stub.c} is the best |
| 361 | organized, and therefore the easiest to read.) |
| 362 | |
| 363 | However, there may be occasions when you need to know something about |
| 364 | the protocol---for example, if there is only one serial port to your |
| 365 | target machine, you might want your program to do something special if |
| 366 | it recognizes a packet meant for @value{GDBN}. |
| 367 | |
| 368 | @cindex protocol, @value{GDBN} remote serial |
| 369 | @cindex serial protocol, @value{GDBN} remote |
| 370 | @cindex remote serial protocol |
| 371 | All @value{GDBN} commands and responses (other than acknowledgements, which |
| 372 | are single characters) are sent as a packet which includes a |
| 373 | checksum. A packet is introduced with the character @samp{$}, and ends |
| 374 | with the character @samp{#} followed by a two-digit checksum: |
| 375 | |
| 376 | @example |
| 377 | $@var{packet info}#@var{checksum} |
| 378 | @end example |
| 379 | |
| 380 | @cindex checksum, for @value{GDBN} remote |
| 381 | @noindent |
| 382 | @var{checksum} is computed as the modulo 256 sum of the @var{packet |
| 383 | info} characters. |
| 384 | |
| 385 | When either the host or the target machine receives a packet, the first |
| 386 | response expected is an acknowledgement: a single character, either |
| 387 | @samp{+} (to indicate the package was received correctly) or @samp{-} |
| 388 | (to request retransmission). |
| 389 | |
| 390 | The host (@value{GDBN}) sends commands, and the target (the debugging stub |
| 391 | incorporated in your program) sends data in response. The target also |
| 392 | sends data when your program stops. |
| 393 | |
| 394 | Command packets are distinguished by their first character, which |
| 395 | identifies the kind of command. |
| 396 | |
| 397 | These are some of the commands currently supported (for a complete list of |
| 398 | commands, look in @file{gdb/remote.c.}): |
| 399 | |
| 400 | @table @code |
| 401 | @item g |
| 402 | Requests the values of CPU registers. |
| 403 | |
| 404 | @item G |
| 405 | Sets the values of CPU registers. |
| 406 | |
| 407 | @item m@var{addr},@var{count} |
| 408 | Read @var{count} bytes at location @var{addr}. |
| 409 | |
| 410 | @item M@var{addr},@var{count}:@dots{} |
| 411 | Write @var{count} bytes at location @var{addr}. |
| 412 | |
| 413 | @need 500 |
| 414 | @item c |
| 415 | @itemx c@var{addr} |
| 416 | Resume execution at the current address (or at @var{addr} if supplied). |
| 417 | |
| 418 | @need 500 |
| 419 | @item s |
| 420 | @itemx s@var{addr} |
| 421 | Step the target program for one instruction, from either the current |
| 422 | program counter or from @var{addr} if supplied. |
| 423 | |
| 424 | @item k |
| 425 | Kill the target program. |
| 426 | |
| 427 | @item ? |
| 428 | Report the most recent signal. To allow you to take advantage of the |
| 429 | @value{GDBN} signal handling commands, one of the functions of the debugging |
| 430 | stub is to report CPU traps as the corresponding POSIX signal values. |
| 431 | |
| 432 | @item T |
| 433 | Allows the remote stub to send only the registers that @value{GDBN} needs |
| 434 | to make a quick decision about single-stepping or conditional breakpoints. |
| 435 | This eliminates the need to fetch the entire register set for each instruction |
| 436 | being stepped through. |
| 437 | |
| 438 | @value{GDBN} now implements a write-through cache for registers and only |
| 439 | re-reads the registers if the target has run. |
| 440 | @end table |
| 441 | |
| 442 | @kindex set remotedebug |
| 443 | @kindex show remotedebug |
| 444 | @cindex packets, reporting on stdout |
| 445 | @cindex serial connections, debugging |
| 446 | If you have trouble with the serial connection, you can use the command |
| 447 | @code{set remotedebug}. This makes @value{GDBN} report on all packets sent |
| 448 | back and forth across the serial line to the remote machine. The |
| 449 | packet-debugging information is printed on the @value{GDBN} standard output |
| 450 | stream. @code{set remotedebug off} turns it off, and @code{show |
| 451 | remotedebug} shows you its current state. |
| 452 | |
| 453 | @node Server |
| 454 | @subsubsection Using the @code{gdbserver} program |
| 455 | |
| 456 | @kindex gdbserver |
| 457 | @cindex remote connection without stubs |
| 458 | @code{gdbserver} is a control program for Unix-like systems, which |
| 459 | allows you to connect your program with a remote @value{GDBN} via |
| 460 | @code{target remote}---but without linking in the usual debugging stub. |
| 461 | |
| 462 | @code{gdbserver} is not a complete replacement for the debugging stubs, |
| 463 | because it requires essentially the same operating-system facilities |
| 464 | that @value{GDBN} itself does. In fact, a system that can run |
| 465 | @code{gdbserver} to connect to a remote @value{GDBN} could also run |
| 466 | @value{GDBN} locally! @code{gdbserver} is sometimes useful nevertheless, |
| 467 | because it is a much smaller program than @value{GDBN} itself. It is |
| 468 | also easier to port than all of @value{GDBN}, so you may be able to get |
| 469 | started more quickly on a new system by using @code{gdbserver}. |
| 470 | Finally, if you develop code for real-time systems, you may find that |
| 471 | the tradeoffs involved in real-time operation make it more convenient to |
| 472 | do as much development work as possible on another system, for example |
| 473 | by cross-compiling. You can use @code{gdbserver} to make a similar |
| 474 | choice for debugging. |
| 475 | |
| 476 | @value{GDBN} and @code{gdbserver} communicate via either a serial line |
| 477 | or a TCP connection, using the standard @value{GDBN} remote serial |
| 478 | protocol. |
| 479 | |
| 480 | @table @emph |
| 481 | @item On the target machine, |
| 482 | you need to have a copy of the program you want to debug. |
| 483 | @code{gdbserver} does not need your program's symbol table, so you can |
| 484 | strip the program if necessary to save space. @value{GDBN} on the host |
| 485 | system does all the symbol handling. |
| 486 | |
| 487 | To use the server, you must tell it how to communicate with @value{GDBN}; |
| 488 | the name of your program; and the arguments for your program. The |
| 489 | syntax is: |
| 490 | |
| 491 | @smallexample |
| 492 | target> gdbserver @var{comm} @var{program} [ @var{args} @dots{} ] |
| 493 | @end smallexample |
| 494 | |
| 495 | @var{comm} is either a device name (to use a serial line) or a TCP |
| 496 | hostname and portnumber. For example, to debug Emacs with the argument |
| 497 | @samp{foo.txt} and communicate with @value{GDBN} over the serial port |
| 498 | @file{/dev/com1}: |
| 499 | |
| 500 | @smallexample |
| 501 | target> gdbserver /dev/com1 emacs foo.txt |
| 502 | @end smallexample |
| 503 | |
| 504 | @code{gdbserver} waits passively for the host @value{GDBN} to communicate |
| 505 | with it. |
| 506 | |
| 507 | To use a TCP connection instead of a serial line: |
| 508 | |
| 509 | @smallexample |
| 510 | target> gdbserver host:2345 emacs foo.txt |
| 511 | @end smallexample |
| 512 | |
| 513 | The only difference from the previous example is the first argument, |
| 514 | specifying that you are communicating with the host @value{GDBN} via |
| 515 | TCP. The @samp{host:2345} argument means that @code{gdbserver} is to |
| 516 | expect a TCP connection from machine @samp{host} to local TCP port 2345. |
| 517 | (Currently, the @samp{host} part is ignored.) You can choose any number |
| 518 | you want for the port number as long as it does not conflict with any |
| 519 | TCP ports already in use on the target system (for example, @code{23} is |
| 520 | reserved for @code{telnet}).@footnote{If you choose a port number that |
| 521 | conflicts with another service, @code{gdbserver} prints an error message |
| 522 | and exits.} You must use the same port number with the host @value{GDBN} |
| 523 | @code{target remote} command. |
| 524 | |
| 525 | @item On the @value{GDBN} host machine, |
| 526 | you need an unstripped copy of your program, since @value{GDBN} needs |
| 527 | symbols and debugging information. Start up @value{GDBN} as usual, |
| 528 | using the name of the local copy of your program as the first argument. |
| 529 | (You may also need the @w{@samp{--baud}} option if the serial line is |
| 530 | running at anything other than 9600 bps.) After that, use @code{target |
| 531 | remote} to establish communications with @code{gdbserver}. Its argument |
| 532 | is either a device name (usually a serial device, like |
| 533 | @file{/dev/ttyb}), or a TCP port descriptor in the form |
| 534 | @code{@var{host}:@var{PORT}}. For example: |
| 535 | |
| 536 | @smallexample |
| 537 | (@value{GDBP}) target remote /dev/ttyb |
| 538 | @end smallexample |
| 539 | |
| 540 | @noindent |
| 541 | communicates with the server via serial line @file{/dev/ttyb}, and |
| 542 | |
| 543 | @smallexample |
| 544 | (@value{GDBP}) target remote the-target:2345 |
| 545 | @end smallexample |
| 546 | |
| 547 | @noindent |
| 548 | communicates via a TCP connection to port 2345 on host @w{@file{the-target}}. |
| 549 | For TCP connections, you must start up @code{gdbserver} prior to using |
| 550 | the @code{target remote} command. Otherwise you may get an error whose |
| 551 | text depends on the host system, but which usually looks something like |
| 552 | @samp{Connection refused}. |
| 553 | @end table |
| 554 | |
| 555 | @node NetWare |
| 556 | @subsubsection Using the @code{gdbserve.nlm} program |
| 557 | |
| 558 | @kindex gdbserve.nlm |
| 559 | @code{gdbserve.nlm} is a control program for NetWare systems, which |
| 560 | allows you to connect your program with a remote @value{GDBN} via |
| 561 | @code{target remote}. |
| 562 | |
| 563 | @value{GDBN} and @code{gdbserve.nlm} communicate via a serial line, |
| 564 | using the standard @value{GDBN} remote serial protocol. |
| 565 | |
| 566 | @table @emph |
| 567 | @item On the target machine, |
| 568 | you need to have a copy of the program you want to debug. |
| 569 | @code{gdbserve.nlm} does not need your program's symbol table, so you |
| 570 | can strip the program if necessary to save space. @value{GDBN} on the |
| 571 | host system does all the symbol handling. |
| 572 | |
| 573 | To use the server, you must tell it how to communicate with |
| 574 | @value{GDBN}; the name of your program; and the arguments for your |
| 575 | program. The syntax is: |
| 576 | |
| 577 | @smallexample |
| 578 | load gdbserve [ BOARD=@var{board} ] [ PORT=@var{port} ] |
| 579 | [ BAUD=@var{baud} ] @var{program} [ @var{args} @dots{} ] |
| 580 | @end smallexample |
| 581 | |
| 582 | @var{board} and @var{port} specify the serial line; @var{baud} specifies |
| 583 | the baud rate used by the connection. @var{port} and @var{node} default |
| 584 | to 0, @var{baud} defaults to 9600 bps. |
| 585 | |
| 586 | For example, to debug Emacs with the argument @samp{foo.txt}and |
| 587 | communicate with @value{GDBN} over serial port number 2 or board 1 |
| 588 | using a 19200 bps connection: |
| 589 | |
| 590 | @smallexample |
| 591 | load gdbserve BOARD=1 PORT=2 BAUD=19200 emacs foo.txt |
| 592 | @end smallexample |
| 593 | |
| 594 | @item On the @value{GDBN} host machine, |
| 595 | you need an unstripped copy of your program, since @value{GDBN} needs |
| 596 | symbols and debugging information. Start up @value{GDBN} as usual, |
| 597 | using the name of the local copy of your program as the first argument. |
| 598 | (You may also need the @w{@samp{--baud}} option if the serial line is |
| 599 | running at anything other than 9600 bps. After that, use @code{target |
| 600 | remote} to establish communications with @code{gdbserve.nlm}. Its |
| 601 | argument is a device name (usually a serial device, like |
| 602 | @file{/dev/ttyb}). For example: |
| 603 | |
| 604 | @smallexample |
| 605 | (@value{GDBP}) target remote /dev/ttyb |
| 606 | @end smallexample |
| 607 | |
| 608 | @noindent |
| 609 | communications with the server via serial line @file{/dev/ttyb}. |
| 610 | @end table |
| 611 | |
| 612 | @node i960-Nindy Remote |
| 613 | @subsection @value{GDBN} with a remote i960 (Nindy) |
| 614 | |
| 615 | @cindex Nindy |
| 616 | @cindex i960 |
| 617 | @dfn{Nindy} is a ROM Monitor program for Intel 960 target systems. When |
| 618 | @value{GDBN} is configured to control a remote Intel 960 using Nindy, you can |
| 619 | tell @value{GDBN} how to connect to the 960 in several ways: |
| 620 | |
| 621 | @itemize @bullet |
| 622 | @item |
| 623 | Through command line options specifying serial port, version of the |
| 624 | Nindy protocol, and communications speed; |
| 625 | |
| 626 | @item |
| 627 | By responding to a prompt on startup; |
| 628 | |
| 629 | @item |
| 630 | By using the @code{target} command at any point during your @value{GDBN} |
| 631 | session. @xref{Target Commands, ,Commands for managing targets}. |
| 632 | |
| 633 | @end itemize |
| 634 | |
| 635 | @menu |
| 636 | * Nindy Startup:: Startup with Nindy |
| 637 | * Nindy Options:: Options for Nindy |
| 638 | * Nindy Reset:: Nindy reset command |
| 639 | @end menu |
| 640 | |
| 641 | @node Nindy Startup |
| 642 | @subsubsection Startup with Nindy |
| 643 | |
| 644 | If you simply start @code{@value{GDBP}} without using any command-line |
| 645 | options, you are prompted for what serial port to use, @emph{before} you |
| 646 | reach the ordinary @value{GDBN} prompt: |
| 647 | |
| 648 | @example |
| 649 | Attach /dev/ttyNN -- specify NN, or "quit" to quit: |
| 650 | @end example |
| 651 | |
| 652 | @noindent |
| 653 | Respond to the prompt with whatever suffix (after @samp{/dev/tty}) |
| 654 | identifies the serial port you want to use. You can, if you choose, |
| 655 | simply start up with no Nindy connection by responding to the prompt |
| 656 | with an empty line. If you do this and later wish to attach to Nindy, |
| 657 | use @code{target} (@pxref{Target Commands, ,Commands for managing targets}). |
| 658 | |
| 659 | @node Nindy Options |
| 660 | @subsubsection Options for Nindy |
| 661 | |
| 662 | These are the startup options for beginning your @value{GDBN} session with a |
| 663 | Nindy-960 board attached: |
| 664 | |
| 665 | @table @code |
| 666 | @item -r @var{port} |
| 667 | Specify the serial port name of a serial interface to be used to connect |
| 668 | to the target system. This option is only available when @value{GDBN} is |
| 669 | configured for the Intel 960 target architecture. You may specify |
| 670 | @var{port} as any of: a full pathname (e.g. @samp{-r /dev/ttya}), a |
| 671 | device name in @file{/dev} (e.g. @samp{-r ttya}), or simply the unique |
| 672 | suffix for a specific @code{tty} (e.g. @samp{-r a}). |
| 673 | |
| 674 | @item -O |
| 675 | (An uppercase letter ``O'', not a zero.) Specify that @value{GDBN} should use |
| 676 | the ``old'' Nindy monitor protocol to connect to the target system. |
| 677 | This option is only available when @value{GDBN} is configured for the Intel 960 |
| 678 | target architecture. |
| 679 | |
| 680 | @quotation |
| 681 | @emph{Warning:} if you specify @samp{-O}, but are actually trying to |
| 682 | connect to a target system that expects the newer protocol, the connection |
| 683 | fails, appearing to be a speed mismatch. @value{GDBN} repeatedly |
| 684 | attempts to reconnect at several different line speeds. You can abort |
| 685 | this process with an interrupt. |
| 686 | @end quotation |
| 687 | |
| 688 | @item -brk |
| 689 | Specify that @value{GDBN} should first send a @code{BREAK} signal to the target |
| 690 | system, in an attempt to reset it, before connecting to a Nindy target. |
| 691 | |
| 692 | @quotation |
| 693 | @emph{Warning:} Many target systems do not have the hardware that this |
| 694 | requires; it only works with a few boards. |
| 695 | @end quotation |
| 696 | @end table |
| 697 | |
| 698 | The standard @samp{-b} option controls the line speed used on the serial |
| 699 | port. |
| 700 | |
| 701 | @c @group |
| 702 | @node Nindy Reset |
| 703 | @subsubsection Nindy reset command |
| 704 | |
| 705 | @table @code |
| 706 | @item reset |
| 707 | @kindex reset |
| 708 | For a Nindy target, this command sends a ``break'' to the remote target |
| 709 | system; this is only useful if the target has been equipped with a |
| 710 | circuit to perform a hard reset (or some other interesting action) when |
| 711 | a break is detected. |
| 712 | @end table |
| 713 | @c @end group |
| 714 | |
| 715 | @node UDI29K Remote |
| 716 | @subsection The UDI protocol for AMD29K |
| 717 | |
| 718 | @cindex UDI |
| 719 | @cindex AMD29K via UDI |
| 720 | @value{GDBN} supports AMD's UDI (``Universal Debugger Interface'') |
| 721 | protocol for debugging the a29k processor family. To use this |
| 722 | configuration with AMD targets running the MiniMON monitor, you need the |
| 723 | program @code{MONTIP}, available from AMD at no charge. You can also |
| 724 | use @value{GDBN} with the UDI-conformant a29k simulator program |
| 725 | @code{ISSTIP}, also available from AMD. |
| 726 | |
| 727 | @table @code |
| 728 | @item target udi @var{keyword} |
| 729 | @kindex udi |
| 730 | Select the UDI interface to a remote a29k board or simulator, where |
| 731 | @var{keyword} is an entry in the AMD configuration file @file{udi_soc}. |
| 732 | This file contains keyword entries which specify parameters used to |
| 733 | connect to a29k targets. If the @file{udi_soc} file is not in your |
| 734 | working directory, you must set the environment variable @samp{UDICONF} |
| 735 | to its pathname. |
| 736 | @end table |
| 737 | |
| 738 | @node EB29K Remote |
| 739 | @subsection The EBMON protocol for AMD29K |
| 740 | |
| 741 | @cindex EB29K board |
| 742 | @cindex running 29K programs |
| 743 | |
| 744 | AMD distributes a 29K development board meant to fit in a PC, together |
| 745 | with a DOS-hosted monitor program called @code{EBMON}. As a shorthand |
| 746 | term, this development system is called the ``EB29K''. To use |
| 747 | @value{GDBN} from a Unix system to run programs on the EB29K board, you |
| 748 | must first connect a serial cable between the PC (which hosts the EB29K |
| 749 | board) and a serial port on the Unix system. In the following, we |
| 750 | assume you've hooked the cable between the PC's @file{COM1} port and |
| 751 | @file{/dev/ttya} on the Unix system. |
| 752 | |
| 753 | @menu |
| 754 | * Comms (EB29K):: Communications setup |
| 755 | * gdb-EB29K:: EB29K cross-debugging |
| 756 | * Remote Log:: Remote log |
| 757 | @end menu |
| 758 | |
| 759 | @node Comms (EB29K) |
| 760 | @subsubsection Communications setup |
| 761 | |
| 762 | The next step is to set up the PC's port, by doing something like this |
| 763 | in DOS on the PC: |
| 764 | |
| 765 | @example |
| 766 | C:\> MODE com1:9600,n,8,1,none |
| 767 | @end example |
| 768 | |
| 769 | @noindent |
| 770 | This example---run on an MS DOS 4.0 system---sets the PC port to 9600 |
| 771 | bps, no parity, eight data bits, one stop bit, and no ``retry'' action; |
| 772 | you must match the communications parameters when establishing the Unix |
| 773 | end of the connection as well. |
| 774 | @c FIXME: Who knows what this "no retry action" crud from the DOS manual may |
| 775 | @c mean? It's optional; leave it out? ---doc@cygnus.com, 25feb91 |
| 776 | |
| 777 | To give control of the PC to the Unix side of the serial line, type |
| 778 | the following at the DOS console: |
| 779 | |
| 780 | @example |
| 781 | C:\> CTTY com1 |
| 782 | @end example |
| 783 | |
| 784 | @noindent |
| 785 | (Later, if you wish to return control to the DOS console, you can use |
| 786 | the command @code{CTTY con}---but you must send it over the device that |
| 787 | had control, in our example over the @file{COM1} serial line). |
| 788 | |
| 789 | From the Unix host, use a communications program such as @code{tip} or |
| 790 | @code{cu} to communicate with the PC; for example, |
| 791 | |
| 792 | @example |
| 793 | cu -s 9600 -l /dev/ttya |
| 794 | @end example |
| 795 | |
| 796 | @noindent |
| 797 | The @code{cu} options shown specify, respectively, the linespeed and the |
| 798 | serial port to use. If you use @code{tip} instead, your command line |
| 799 | may look something like the following: |
| 800 | |
| 801 | @example |
| 802 | tip -9600 /dev/ttya |
| 803 | @end example |
| 804 | |
| 805 | @noindent |
| 806 | Your system may require a different name where we show |
| 807 | @file{/dev/ttya} as the argument to @code{tip}. The communications |
| 808 | parameters, including which port to use, are associated with the |
| 809 | @code{tip} argument in the ``remote'' descriptions file---normally the |
| 810 | system table @file{/etc/remote}. |
| 811 | @c FIXME: What if anything needs doing to match the "n,8,1,none" part of |
| 812 | @c the DOS side's comms setup? cu can support -o (odd |
| 813 | @c parity), -e (even parity)---apparently no settings for no parity or |
| 814 | @c for character size. Taken from stty maybe...? John points out tip |
| 815 | @c can set these as internal variables, eg ~s parity=none; man stty |
| 816 | @c suggests that it *might* work to stty these options with stdin or |
| 817 | @c stdout redirected... ---doc@cygnus.com, 25feb91 |
| 818 | |
| 819 | @kindex EBMON |
| 820 | Using the @code{tip} or @code{cu} connection, change the DOS working |
| 821 | directory to the directory containing a copy of your 29K program, then |
| 822 | start the PC program @code{EBMON} (an EB29K control program supplied |
| 823 | with your board by AMD). You should see an initial display from |
| 824 | @code{EBMON} similar to the one that follows, ending with the |
| 825 | @code{EBMON} prompt @samp{#}--- |
| 826 | |
| 827 | @example |
| 828 | C:\> G: |
| 829 | |
| 830 | G:\> CD \usr\joe\work29k |
| 831 | |
| 832 | G:\USR\JOE\WORK29K> EBMON |
| 833 | Am29000 PC Coprocessor Board Monitor, version 3.0-18 |
| 834 | Copyright 1990 Advanced Micro Devices, Inc. |
| 835 | Written by Gibbons and Associates, Inc. |
| 836 | |
| 837 | Enter '?' or 'H' for help |
| 838 | |
| 839 | PC Coprocessor Type = EB29K |
| 840 | I/O Base = 0x208 |
| 841 | Memory Base = 0xd0000 |
| 842 | |
| 843 | Data Memory Size = 2048KB |
| 844 | Available I-RAM Range = 0x8000 to 0x1fffff |
| 845 | Available D-RAM Range = 0x80002000 to 0x801fffff |
| 846 | |
| 847 | PageSize = 0x400 |
| 848 | Register Stack Size = 0x800 |
| 849 | Memory Stack Size = 0x1800 |
| 850 | |
| 851 | CPU PRL = 0x3 |
| 852 | Am29027 Available = No |
| 853 | Byte Write Available = Yes |
| 854 | |
| 855 | # ~. |
| 856 | @end example |
| 857 | |
| 858 | Then exit the @code{cu} or @code{tip} program (done in the example by |
| 859 | typing @code{~.} at the @code{EBMON} prompt). @code{EBMON} keeps |
| 860 | running, ready for @value{GDBN} to take over. |
| 861 | |
| 862 | For this example, we've assumed what is probably the most convenient |
| 863 | way to make sure the same 29K program is on both the PC and the Unix |
| 864 | system: a PC/NFS connection that establishes ``drive @code{G:}'' on the |
| 865 | PC as a file system on the Unix host. If you do not have PC/NFS or |
| 866 | something similar connecting the two systems, you must arrange some |
| 867 | other way---perhaps floppy-disk transfer---of getting the 29K program |
| 868 | from the Unix system to the PC; @value{GDBN} does @emph{not} download it over the |
| 869 | serial line. |
| 870 | |
| 871 | @node gdb-EB29K |
| 872 | @subsubsection EB29K cross-debugging |
| 873 | |
| 874 | Finally, @code{cd} to the directory containing an image of your 29K |
| 875 | program on the Unix system, and start @value{GDBN}---specifying as argument the |
| 876 | name of your 29K program: |
| 877 | |
| 878 | @example |
| 879 | cd /usr/joe/work29k |
| 880 | @value{GDBP} myfoo |
| 881 | @end example |
| 882 | |
| 883 | @need 500 |
| 884 | Now you can use the @code{target} command: |
| 885 | |
| 886 | @example |
| 887 | target amd-eb /dev/ttya 9600 MYFOO |
| 888 | @c FIXME: test above 'target amd-eb' as spelled, with caps! caps are meant to |
| 889 | @c emphasize that this is the name as seen by DOS (since I think DOS is |
| 890 | @c single-minded about case of letters). ---doc@cygnus.com, 25feb91 |
| 891 | @end example |
| 892 | |
| 893 | @noindent |
| 894 | In this example, we've assumed your program is in a file called |
| 895 | @file{myfoo}. Note that the filename given as the last argument to |
| 896 | @code{target amd-eb} should be the name of the program as it appears to DOS. |
| 897 | In our example this is simply @code{MYFOO}, but in general it can include |
| 898 | a DOS path, and depending on your transfer mechanism may not resemble |
| 899 | the name on the Unix side. |
| 900 | |
| 901 | At this point, you can set any breakpoints you wish; when you are ready |
| 902 | to see your program run on the 29K board, use the @value{GDBN} command |
| 903 | @code{run}. |
| 904 | |
| 905 | To stop debugging the remote program, use the @value{GDBN} @code{detach} |
| 906 | command. |
| 907 | |
| 908 | To return control of the PC to its console, use @code{tip} or @code{cu} |
| 909 | once again, after your @value{GDBN} session has concluded, to attach to |
| 910 | @code{EBMON}. You can then type the command @code{q} to shut down |
| 911 | @code{EBMON}, returning control to the DOS command-line interpreter. |
| 912 | Type @code{CTTY con} to return command input to the main DOS console, |
| 913 | and type @kbd{~.} to leave @code{tip} or @code{cu}. |
| 914 | |
| 915 | @node Remote Log |
| 916 | @subsubsection Remote log |
| 917 | @kindex eb.log |
| 918 | @cindex log file for EB29K |
| 919 | |
| 920 | The @code{target amd-eb} command creates a file @file{eb.log} in the |
| 921 | current working directory, to help debug problems with the connection. |
| 922 | @file{eb.log} records all the output from @code{EBMON}, including echoes |
| 923 | of the commands sent to it. Running @samp{tail -f} on this file in |
| 924 | another window often helps to understand trouble with @code{EBMON}, or |
| 925 | unexpected events on the PC side of the connection. |
| 926 | |
| 927 | @node ST2000 Remote |
| 928 | @subsection @value{GDBN} with a Tandem ST2000 |
| 929 | |
| 930 | To connect your ST2000 to the host system, see the manufacturer's |
| 931 | manual. Once the ST2000 is physically attached, you can run: |
| 932 | |
| 933 | @example |
| 934 | target st2000 @var{dev} @var{speed} |
| 935 | @end example |
| 936 | |
| 937 | @noindent |
| 938 | to establish it as your debugging environment. @var{dev} is normally |
| 939 | the name of a serial device, such as @file{/dev/ttya}, connected to the |
| 940 | ST2000 via a serial line. You can instead specify @var{dev} as a TCP |
| 941 | connection (for example, to a serial line attached via a terminal |
| 942 | concentrator) using the syntax @code{@var{hostname}:@var{portnumber}}. |
| 943 | |
| 944 | The @code{load} and @code{attach} commands are @emph{not} defined for |
| 945 | this target; you must load your program into the ST2000 as you normally |
| 946 | would for standalone operation. @value{GDBN} reads debugging information |
| 947 | (such as symbols) from a separate, debugging version of the program |
| 948 | available on your host computer. |
| 949 | @c FIXME!! This is terribly vague; what little content is here is |
| 950 | @c basically hearsay. |
| 951 | |
| 952 | @cindex ST2000 auxiliary commands |
| 953 | These auxiliary @value{GDBN} commands are available to help you with the ST2000 |
| 954 | environment: |
| 955 | |
| 956 | @table @code |
| 957 | @item st2000 @var{command} |
| 958 | @kindex st2000 @var{cmd} |
| 959 | @cindex STDBUG commands (ST2000) |
| 960 | @cindex commands to STDBUG (ST2000) |
| 961 | Send a @var{command} to the STDBUG monitor. See the manufacturer's |
| 962 | manual for available commands. |
| 963 | |
| 964 | @item connect |
| 965 | @cindex connect (to STDBUG) |
| 966 | Connect the controlling terminal to the STDBUG command monitor. When |
| 967 | you are done interacting with STDBUG, typing either of two character |
| 968 | sequences gets you back to the @value{GDBN} command prompt: |
| 969 | @kbd{@key{RET}~.} (Return, followed by tilde and period) or |
| 970 | @kbd{@key{RET}~@key{C-d}} (Return, followed by tilde and control-D). |
| 971 | @end table |
| 972 | |
| 973 | @node VxWorks Remote |
| 974 | @subsection @value{GDBN} and VxWorks |
| 975 | |
| 976 | @cindex VxWorks |
| 977 | |
| 978 | @value{GDBN} enables developers to spawn and debug tasks running on networked |
| 979 | VxWorks targets from a Unix host. Already-running tasks spawned from |
| 980 | the VxWorks shell can also be debugged. @value{GDBN} uses code that runs on |
| 981 | both the Unix host and on the VxWorks target. The program |
| 982 | @code{gdb} is installed and executed on the Unix host. (It may be |
| 983 | installed with the name @code{vxgdb}, to distinguish it from a |
| 984 | @value{GDBN} for debugging programs on the host itself.) |
| 985 | |
| 986 | @table @code |
| 987 | @item VxWorks-timeout @var{args} |
| 988 | @kindex vxworks-timeout |
| 989 | All VxWorks-based targets now support the option @code{vxworks-timeout}. |
| 990 | This option is set by the user, and @var{args} represents the number of |
| 991 | seconds @value{GDBN} waits for responses to rpc's. You might use this if |
| 992 | your VxWorks target is a slow software simulator or is on the far side |
| 993 | of a thin network line. |
| 994 | @end table |
| 995 | |
| 996 | The following information on connecting to VxWorks was current when |
| 997 | this manual was produced; newer releases of VxWorks may use revised |
| 998 | procedures. |
| 999 | |
| 1000 | @kindex INCLUDE_RDB |
| 1001 | To use @value{GDBN} with VxWorks, you must rebuild your VxWorks kernel |
| 1002 | to include the remote debugging interface routines in the VxWorks |
| 1003 | library @file{rdb.a}. To do this, define @code{INCLUDE_RDB} in the |
| 1004 | VxWorks configuration file @file{configAll.h} and rebuild your VxWorks |
| 1005 | kernel. The resulting kernel contains @file{rdb.a}, and spawns the |
| 1006 | source debugging task @code{tRdbTask} when VxWorks is booted. For more |
| 1007 | information on configuring and remaking VxWorks, see the manufacturer's |
| 1008 | manual. |
| 1009 | @c VxWorks, see the @cite{VxWorks Programmer's Guide}. |
| 1010 | |
| 1011 | Once you have included @file{rdb.a} in your VxWorks system image and set |
| 1012 | your Unix execution search path to find @value{GDBN}, you are ready to |
| 1013 | run @value{GDBN}. From your Unix host, run @code{gdb} (or @code{vxgdb}, |
| 1014 | depending on your installation). |
| 1015 | |
| 1016 | @value{GDBN} comes up showing the prompt: |
| 1017 | |
| 1018 | @example |
| 1019 | (vxgdb) |
| 1020 | @end example |
| 1021 | |
| 1022 | @menu |
| 1023 | * VxWorks Connection:: Connecting to VxWorks |
| 1024 | * VxWorks Download:: VxWorks download |
| 1025 | * VxWorks Attach:: Running tasks |
| 1026 | @end menu |
| 1027 | |
| 1028 | @node VxWorks Connection |
| 1029 | @subsubsection Connecting to VxWorks |
| 1030 | |
| 1031 | The @value{GDBN} command @code{target} lets you connect to a VxWorks target on the |
| 1032 | network. To connect to a target whose host name is ``@code{tt}'', type: |
| 1033 | |
| 1034 | @example |
| 1035 | (vxgdb) target vxworks tt |
| 1036 | @end example |
| 1037 | |
| 1038 | @need 750 |
| 1039 | @value{GDBN} displays messages like these: |
| 1040 | |
| 1041 | @smallexample |
| 1042 | Attaching remote machine across net... |
| 1043 | Connected to tt. |
| 1044 | @end smallexample |
| 1045 | |
| 1046 | @need 1000 |
| 1047 | @value{GDBN} then attempts to read the symbol tables of any object modules |
| 1048 | loaded into the VxWorks target since it was last booted. @value{GDBN} locates |
| 1049 | these files by searching the directories listed in the command search |
| 1050 | path (@pxref{Environment, ,Your program's environment}); if it fails |
| 1051 | to find an object file, it displays a message such as: |
| 1052 | |
| 1053 | @example |
| 1054 | prog.o: No such file or directory. |
| 1055 | @end example |
| 1056 | |
| 1057 | When this happens, add the appropriate directory to the search path with |
| 1058 | the @value{GDBN} command @code{path}, and execute the @code{target} |
| 1059 | command again. |
| 1060 | |
| 1061 | @node VxWorks Download |
| 1062 | @subsubsection VxWorks download |
| 1063 | |
| 1064 | @cindex download to VxWorks |
| 1065 | If you have connected to the VxWorks target and you want to debug an |
| 1066 | object that has not yet been loaded, you can use the @value{GDBN} |
| 1067 | @code{load} command to download a file from Unix to VxWorks |
| 1068 | incrementally. The object file given as an argument to the @code{load} |
| 1069 | command is actually opened twice: first by the VxWorks target in order |
| 1070 | to download the code, then by @value{GDBN} in order to read the symbol |
| 1071 | table. This can lead to problems if the current working directories on |
| 1072 | the two systems differ. If both systems have NFS mounted the same |
| 1073 | filesystems, you can avoid these problems by using absolute paths. |
| 1074 | Otherwise, it is simplest to set the working directory on both systems |
| 1075 | to the directory in which the object file resides, and then to reference |
| 1076 | the file by its name, without any path. For instance, a program |
| 1077 | @file{prog.o} may reside in @file{@var{vxpath}/vw/demo/rdb} in VxWorks |
| 1078 | and in @file{@var{hostpath}/vw/demo/rdb} on the host. To load this |
| 1079 | program, type this on VxWorks: |
| 1080 | |
| 1081 | @example |
| 1082 | -> cd "@var{vxpath}/vw/demo/rdb" |
| 1083 | @end example |
| 1084 | v |
| 1085 | Then, in @value{GDBN}, type: |
| 1086 | |
| 1087 | @example |
| 1088 | (vxgdb) cd @var{hostpath}/vw/demo/rdb |
| 1089 | (vxgdb) load prog.o |
| 1090 | @end example |
| 1091 | |
| 1092 | @value{GDBN} displays a response similar to this: |
| 1093 | |
| 1094 | @smallexample |
| 1095 | Reading symbol data from wherever/vw/demo/rdb/prog.o... done. |
| 1096 | @end smallexample |
| 1097 | |
| 1098 | You can also use the @code{load} command to reload an object module |
| 1099 | after editing and recompiling the corresponding source file. Note that |
| 1100 | this makes @value{GDBN} delete all currently-defined breakpoints, |
| 1101 | auto-displays, and convenience variables, and to clear the value |
| 1102 | history. (This is necessary in order to preserve the integrity of |
| 1103 | debugger data structures that reference the target system's symbol |
| 1104 | table.) |
| 1105 | |
| 1106 | @node VxWorks Attach |
| 1107 | @subsubsection Running tasks |
| 1108 | |
| 1109 | @cindex running VxWorks tasks |
| 1110 | You can also attach to an existing task using the @code{attach} command as |
| 1111 | follows: |
| 1112 | |
| 1113 | @example |
| 1114 | (vxgdb) attach @var{task} |
| 1115 | @end example |
| 1116 | |
| 1117 | @noindent |
| 1118 | where @var{task} is the VxWorks hexadecimal task ID. The task can be running |
| 1119 | or suspended when you attach to it. Running tasks are suspended at |
| 1120 | the time of attachment. |
| 1121 | |
| 1122 | @node Sparclet Remote |
| 1123 | @subsection @value{GDBN} and Sparclet |
| 1124 | @cindex Sparclet |
| 1125 | |
| 1126 | @value{GDBN} enables developers to debug tasks running on |
| 1127 | Sparclet targets from a Unix host. |
| 1128 | @value{GDBN} uses code that runs on |
| 1129 | both the Unix host and on the Sparclet target. The program |
| 1130 | @code{gdb} is installed and executed on the Unix host. |
| 1131 | |
| 1132 | @table @code |
| 1133 | @item timeout @var{args} |
| 1134 | @kindex remotetimeout |
| 1135 | @value{GDBN} now supports the option @code{remotetimeout}. |
| 1136 | This option is set by the user, and @var{args} represents the number of |
| 1137 | seconds @value{GDBN} waits for responses. |
| 1138 | @end table |
| 1139 | |
| 1140 | @kindex Compiling |
| 1141 | When compiling for debugging, include the options "-g" to get debug |
| 1142 | information and "-Ttext" to relocate the program to where you wish to |
| 1143 | load it on the target. You may also want to add the options "-n" or |
| 1144 | "-N" in order to reduce the size of the sections. |
| 1145 | |
| 1146 | @example |
| 1147 | sparclet-aout-gcc prog.c -Ttext 0x12010000 -g -o prog -N |
| 1148 | @end example |
| 1149 | |
| 1150 | You can use objdump to verify that the addresses are what you intended. |
| 1151 | |
| 1152 | @example |
| 1153 | sparclet-aout-objdump --headers --syms prog |
| 1154 | @end example |
| 1155 | |
| 1156 | @kindex Running |
| 1157 | Once you have set |
| 1158 | your Unix execution search path to find @value{GDBN}, you are ready to |
| 1159 | run @value{GDBN}. From your Unix host, run @code{gdb} |
| 1160 | (or @code{sparclet-aout-gdb}, depending on your installation). |
| 1161 | |
| 1162 | @value{GDBN} comes up showing the prompt: |
| 1163 | |
| 1164 | @example |
| 1165 | (gdbslet) |
| 1166 | @end example |
| 1167 | |
| 1168 | @menu |
| 1169 | * Sparclet File:: Setting the file to debug |
| 1170 | * Sparclet Connection:: Connecting to Sparclet |
| 1171 | * Sparclet Download:: Sparclet download |
| 1172 | * Sparclet Execution:: Running and debugging |
| 1173 | @end menu |
| 1174 | |
| 1175 | @node Sparclet File |
| 1176 | @subsubsection Setting file to debug |
| 1177 | |
| 1178 | The @value{GDBN} command @code{file} lets you choose with program to debug. |
| 1179 | |
| 1180 | @example |
| 1181 | (gdbslet) file prog |
| 1182 | @end example |
| 1183 | |
| 1184 | @need 1000 |
| 1185 | @value{GDBN} then attempts to read the symbol table of @file{prog}. |
| 1186 | @value{GDBN} locates |
| 1187 | the file by searching the directories listed in the command search |
| 1188 | path. |
| 1189 | If the file was compiled with debug information (option "-g"), source |
| 1190 | files will be searched as well. |
| 1191 | @value{GDBN} locates |
| 1192 | the source files by searching the directories listed in the directory search |
| 1193 | path (@pxref{Environment, ,Your program's environment}). |
| 1194 | If it fails |
| 1195 | to find a file, it displays a message such as: |
| 1196 | |
| 1197 | @example |
| 1198 | prog: No such file or directory. |
| 1199 | @end example |
| 1200 | |
| 1201 | When this happens, add the appropriate directories to the search paths with |
| 1202 | the @value{GDBN} commands @code{path} and @code{dir}, and execute the |
| 1203 | @code{target} command again. |
| 1204 | |
| 1205 | @node Sparclet Connection |
| 1206 | @subsubsection Connecting to Sparclet |
| 1207 | |
| 1208 | The @value{GDBN} command @code{target} lets you connect to a Sparclet target. |
| 1209 | To connect to a target on serial port ``@code{ttya}'', type: |
| 1210 | |
| 1211 | @example |
| 1212 | (gdbslet) target sparclet /dev/ttya |
| 1213 | Remote target sparclet connected to /dev/ttya |
| 1214 | main () at ../prog.c:3 |
| 1215 | @end example |
| 1216 | |
| 1217 | @need 750 |
| 1218 | @value{GDBN} displays messages like these: |
| 1219 | |
| 1220 | @smallexample |
| 1221 | Connected to ttya. |
| 1222 | @end smallexample |
| 1223 | |
| 1224 | @node Sparclet Download |
| 1225 | @subsubsection Sparclet download |
| 1226 | |
| 1227 | @cindex download to Sparclet |
| 1228 | Once connected to the Sparclet target, |
| 1229 | you can use the @value{GDBN} |
| 1230 | @code{load} command to download the file from the host to the target. |
| 1231 | The file name and load offset should be given as arguments to the @code{load} |
| 1232 | command. |
| 1233 | Since the file format is aout, the program must be loaded to the starting |
| 1234 | address. You can use objdump to find out what this value is. The load |
| 1235 | offset is an offset which is added to the VMA (virtual memory address) |
| 1236 | of each of the file's sections. |
| 1237 | For instance, if the program |
| 1238 | @file{prog} was linked to text address 0x1201000, with data at 0x12010160 |
| 1239 | and bss at 0x12010170, in @value{GDBN}, type: |
| 1240 | |
| 1241 | @example |
| 1242 | (gdbslet) load prog 0x12010000 |
| 1243 | Loading section .text, size 0xdb0 vma 0x12010000 |
| 1244 | @end example |
| 1245 | |
| 1246 | If the code is loaded at a different address then what the program was linked |
| 1247 | to, you may need to use the @code{section} and @code{add-symbol-file} commands |
| 1248 | to tell @value{GDBN} where to map the symbol table. |
| 1249 | |
| 1250 | @node Sparclet Execution |
| 1251 | @subsubsection Running and debugging |
| 1252 | |
| 1253 | @cindex running and debugging Sparclet programs |
| 1254 | You can now begin debugging the task using @value{GDBN}'s execution control |
| 1255 | commands, @code{b}, @code{step}, @code{run}, etc. See the @value{GDBN} |
| 1256 | manual for the list of commands. |
| 1257 | |
| 1258 | @example |
| 1259 | (gdbslet) b main |
| 1260 | Breakpoint 1 at 0x12010000: file prog.c, line 3. |
| 1261 | (gdbslet) run |
| 1262 | Starting program: prog |
| 1263 | Breakpoint 1, main (argc=1, argv=0xeffff21c) at prog.c:3 |
| 1264 | 3 char *symarg = 0; |
| 1265 | (gdbslet) step |
| 1266 | 4 char *execarg = "hello!"; |
| 1267 | (gdbslet) |
| 1268 | @end example |
| 1269 | |
| 1270 | @node Hitachi Remote |
| 1271 | @subsection @value{GDBN} and Hitachi microprocessors |
| 1272 | @value{GDBN} needs to know these things to talk to your |
| 1273 | Hitachi SH, H8/300, or H8/500: |
| 1274 | |
| 1275 | @enumerate |
| 1276 | @item |
| 1277 | that you want to use @samp{target hms}, the remote debugging interface |
| 1278 | for Hitachi microprocessors, or @samp{target e7000}, the in-circuit |
| 1279 | emulator for the Hitachi SH and the Hitachi 300H. (@samp{target hms} is |
| 1280 | the default when GDB is configured specifically for the Hitachi SH, |
| 1281 | H8/300, or H8/500.) |
| 1282 | |
| 1283 | @item |
| 1284 | what serial device connects your host to your Hitachi board (the first |
| 1285 | serial device available on your host is the default). |
| 1286 | |
| 1287 | @item |
| 1288 | what speed to use over the serial device. |
| 1289 | @end enumerate |
| 1290 | |
| 1291 | @menu |
| 1292 | * Hitachi Boards:: Connecting to Hitachi boards. |
| 1293 | * Hitachi ICE:: Using the E7000 In-Circuit Emulator. |
| 1294 | * Hitachi Special:: Special @value{GDBN} commands for Hitachi micros. |
| 1295 | @end menu |
| 1296 | |
| 1297 | @node Hitachi Boards |
| 1298 | @subsubsection Connecting to Hitachi boards |
| 1299 | |
| 1300 | @c only for Unix hosts |
| 1301 | @kindex device |
| 1302 | @cindex serial device, Hitachi micros |
| 1303 | Use the special @code{@value{GDBP}} command @samp{device @var{port}} if you |
| 1304 | need to explicitly set the serial device. The default @var{port} is the |
| 1305 | first available port on your host. This is only necessary on Unix |
| 1306 | hosts, where it is typically something like @file{/dev/ttya}. |
| 1307 | |
| 1308 | @kindex speed |
| 1309 | @cindex serial line speed, Hitachi micros |
| 1310 | @code{@value{GDBP}} has another special command to set the communications |
| 1311 | speed: @samp{speed @var{bps}}. This command also is only used from Unix |
| 1312 | hosts; on DOS hosts, set the line speed as usual from outside GDB with |
| 1313 | the DOS @kbd{mode} command (for instance, @w{@samp{mode |
| 1314 | com2:9600,n,8,1,p}} for a 9600 bps connection). |
| 1315 | |
| 1316 | The @samp{device} and @samp{speed} commands are available only when you |
| 1317 | use a Unix host to debug your Hitachi microprocessor programs. If you |
| 1318 | use a DOS host, |
| 1319 | @value{GDBN} depends on an auxiliary terminate-and-stay-resident program |
| 1320 | called @code{asynctsr} to communicate with the development board |
| 1321 | through a PC serial port. You must also use the DOS @code{mode} command |
| 1322 | to set up the serial port on the DOS side. |
| 1323 | |
| 1324 | The following sample session illustrates the steps needed to start a |
| 1325 | program under @value{GDBN} control on an H8/300. The example uses a |
| 1326 | sample H8/300 program called @file{t.x}. The procedure is the same for |
| 1327 | the Hitachi SH and the H8/500. |
| 1328 | |
| 1329 | First hook up your development board. In this example, we use a |
| 1330 | board attached to serial port @code{COM2}; if you use a different serial |
| 1331 | port, substitute its name in the argument of the @code{mode} command. |
| 1332 | When you call @code{asynctsr}, the auxiliary comms program used by the |
| 1333 | degugger, you give it just the numeric part of the serial port's name; |
| 1334 | for example, @samp{asyncstr 2} below runs @code{asyncstr} on |
| 1335 | @code{COM2}. |
| 1336 | |
| 1337 | @example |
| 1338 | C:\H8300\TEST> asynctsr 2 |
| 1339 | C:\H8300\TEST> mode com2:9600,n,8,1,p |
| 1340 | |
| 1341 | Resident portion of MODE loaded |
| 1342 | |
| 1343 | COM2: 9600, n, 8, 1, p |
| 1344 | |
| 1345 | @end example |
| 1346 | |
| 1347 | @quotation |
| 1348 | @emph{Warning:} We have noticed a bug in PC-NFS that conflicts with |
| 1349 | @code{asynctsr}. If you also run PC-NFS on your DOS host, you may need to |
| 1350 | disable it, or even boot without it, to use @code{asynctsr} to control |
| 1351 | your development board. |
| 1352 | @end quotation |
| 1353 | |
| 1354 | @kindex target hms |
| 1355 | Now that serial communications are set up, and the development board is |
| 1356 | connected, you can start up @value{GDBN}. Call @code{@value{GDBP}} with |
| 1357 | the name of your program as the argument. @code{@value{GDBP}} prompts |
| 1358 | you, as usual, with the prompt @samp{(@value{GDBP})}. Use two special |
| 1359 | commands to begin your debugging session: @samp{target hms} to specify |
| 1360 | cross-debugging to the Hitachi board, and the @code{load} command to |
| 1361 | download your program to the board. @code{load} displays the names of |
| 1362 | the program's sections, and a @samp{*} for each 2K of data downloaded. |
| 1363 | (If you want to refresh @value{GDBN} data on symbols or on the |
| 1364 | executable file without downloading, use the @value{GDBN} commands |
| 1365 | @code{file} or @code{symbol-file}. These commands, and @code{load} |
| 1366 | itself, are described in @ref{Files,,Commands to specify files}.) |
| 1367 | |
| 1368 | @smallexample |
| 1369 | (eg-C:\H8300\TEST) @value{GDBP} t.x |
| 1370 | GDB is free software and you are welcome to distribute copies |
| 1371 | of it under certain conditions; type "show copying" to see |
| 1372 | the conditions. |
| 1373 | There is absolutely no warranty for GDB; type "show warranty" |
| 1374 | for details. |
| 1375 | GDB @value{GDBVN}, Copyright 1992 Free Software Foundation, Inc... |
| 1376 | (gdb) target hms |
| 1377 | Connected to remote H8/300 HMS system. |
| 1378 | (gdb) load t.x |
| 1379 | .text : 0x8000 .. 0xabde *********** |
| 1380 | .data : 0xabde .. 0xad30 * |
| 1381 | .stack : 0xf000 .. 0xf014 * |
| 1382 | @end smallexample |
| 1383 | |
| 1384 | At this point, you're ready to run or debug your program. From here on, |
| 1385 | you can use all the usual @value{GDBN} commands. The @code{break} command |
| 1386 | sets breakpoints; the @code{run} command starts your program; |
| 1387 | @code{print} or @code{x} display data; the @code{continue} command |
| 1388 | resumes execution after stopping at a breakpoint. You can use the |
| 1389 | @code{help} command at any time to find out more about @value{GDBN} commands. |
| 1390 | |
| 1391 | Remember, however, that @emph{operating system} facilities aren't |
| 1392 | available on your development board; for example, if your program hangs, |
| 1393 | you can't send an interrupt---but you can press the @sc{reset} switch! |
| 1394 | |
| 1395 | Use the @sc{reset} button on the development board |
| 1396 | @itemize @bullet |
| 1397 | @item |
| 1398 | to interrupt your program (don't use @kbd{ctl-C} on the DOS host---it has |
| 1399 | no way to pass an interrupt signal to the development board); and |
| 1400 | |
| 1401 | @item |
| 1402 | to return to the @value{GDBN} command prompt after your program finishes |
| 1403 | normally. The communications protocol provides no other way for @value{GDBN} |
| 1404 | to detect program completion. |
| 1405 | @end itemize |
| 1406 | |
| 1407 | In either case, @value{GDBN} sees the effect of a @sc{reset} on the |
| 1408 | development board as a ``normal exit'' of your program. |
| 1409 | |
| 1410 | @node Hitachi ICE |
| 1411 | @subsubsection Using the E7000 in-circuit emulator |
| 1412 | |
| 1413 | @kindex target e7000 |
| 1414 | You can use the E7000 in-circuit emulator to develop code for either the |
| 1415 | Hitachi SH or the H8/300H. Use one of these forms of the @samp{target |
| 1416 | e7000} command to connect @value{GDBN} to your E7000: |
| 1417 | |
| 1418 | @table @code |
| 1419 | @item target e7000 @var{port} @var{speed} |
| 1420 | Use this form if your E7000 is connected to a serial port. The |
| 1421 | @var{port} argument identifies what serial port to use (for example, |
| 1422 | @samp{com2}). The third argument is the line speed in bits per second |
| 1423 | (for example, @samp{9600}). |
| 1424 | |
| 1425 | @item target e7000 @var{hostname} |
| 1426 | If your E7000 is installed as a host on a TCP/IP network, you can just |
| 1427 | specify its hostname; @value{GDBN} uses @code{telnet} to connect. |
| 1428 | @end table |
| 1429 | |
| 1430 | @node Hitachi Special |
| 1431 | @subsubsection Special @value{GDBN} commands for Hitachi micros |
| 1432 | |
| 1433 | Some @value{GDBN} commands are available only on the H8/300 or the |
| 1434 | H8/500 configurations: |
| 1435 | |
| 1436 | @table @code |
| 1437 | @kindex set machine |
| 1438 | @kindex show machine |
| 1439 | @item set machine h8300 |
| 1440 | @itemx set machine h8300h |
| 1441 | Condition @value{GDBN} for one of the two variants of the H8/300 |
| 1442 | architecture with @samp{set machine}. You can use @samp{show machine} |
| 1443 | to check which variant is currently in effect. |
| 1444 | |
| 1445 | @kindex set memory @var{mod} |
| 1446 | @cindex memory models, H8/500 |
| 1447 | @item set memory @var{mod} |
| 1448 | @itemx show memory |
| 1449 | Specify which H8/500 memory model (@var{mod}) you are using with |
| 1450 | @samp{set memory}; check which memory model is in effect with @samp{show |
| 1451 | memory}. The accepted values for @var{mod} are @code{small}, |
| 1452 | @code{big}, @code{medium}, and @code{compact}. |
| 1453 | @end table |
| 1454 | |
| 1455 | @node MIPS Remote |
| 1456 | @subsection @value{GDBN} and remote MIPS boards |
| 1457 | |
| 1458 | @cindex MIPS boards |
| 1459 | @value{GDBN} can use the MIPS remote debugging protocol to talk to a |
| 1460 | MIPS board attached to a serial line. This is available when |
| 1461 | you configure @value{GDBN} with @samp{--target=mips-idt-ecoff}. |
| 1462 | |
| 1463 | @need 1000 |
| 1464 | Use these @value{GDBN} commands to specify the connection to your target board: |
| 1465 | |
| 1466 | @table @code |
| 1467 | @item target mips @var{port} |
| 1468 | @kindex target mips @var{port} |
| 1469 | To run a program on the board, start up @code{@value{GDBP}} with the |
| 1470 | name of your program as the argument. To connect to the board, use the |
| 1471 | command @samp{target mips @var{port}}, where @var{port} is the name of |
| 1472 | the serial port connected to the board. If the program has not already |
| 1473 | been downloaded to the board, you may use the @code{load} command to |
| 1474 | download it. You can then use all the usual @value{GDBN} commands. |
| 1475 | |
| 1476 | For example, this sequence connects to the target board through a serial |
| 1477 | port, and loads and runs a program called @var{prog} through the |
| 1478 | debugger: |
| 1479 | |
| 1480 | @example |
| 1481 | host$ @value{GDBP} @var{prog} |
| 1482 | GDB is free software and @dots{} |
| 1483 | (gdb) target mips /dev/ttyb |
| 1484 | (gdb) load @var{prog} |
| 1485 | (gdb) run |
| 1486 | @end example |
| 1487 | |
| 1488 | @item target mips @var{hostname}:@var{portnumber} |
| 1489 | On some @value{GDBN} host configurations, you can specify a TCP |
| 1490 | connection (for instance, to a serial line managed by a terminal |
| 1491 | concentrator) instead of a serial port, using the syntax |
| 1492 | @samp{@var{hostname}:@var{portnumber}}. |
| 1493 | |
| 1494 | @item target pmon @var{port} |
| 1495 | @kindex target pmon @var{port} |
| 1496 | |
| 1497 | @item target ddb @var{port} |
| 1498 | @kindex target ddb @var{port} |
| 1499 | |
| 1500 | @item target lsi @var{port} |
| 1501 | @kindex target lsi @var{port} |
| 1502 | |
| 1503 | @end table |
| 1504 | |
| 1505 | |
| 1506 | @noindent |
| 1507 | @value{GDBN} also supports these special commands for MIPS targets: |
| 1508 | |
| 1509 | @table @code |
| 1510 | @item set processor @var{args} |
| 1511 | @itemx show processor |
| 1512 | @kindex set processor @var{args} |
| 1513 | @kindex show processor |
| 1514 | Use the @code{set processor} command to set the type of MIPS |
| 1515 | processor when you want to access processor-type-specific registers. |
| 1516 | For example, @code{set processor @var{r3041}} tells @value{GDBN} |
| 1517 | to use the CPO registers appropriate for the 3041 chip. |
| 1518 | Use the @code{show processor} command to see what MIPS processor @value{GDBN} |
| 1519 | is using. Use the @code{info reg} command to see what registers |
| 1520 | @value{GDBN} is using. |
| 1521 | |
| 1522 | @item set mipsfpu double |
| 1523 | @itemx set mipsfpu single |
| 1524 | @itemx set mipsfpu none |
| 1525 | @itemx show mipsfpu |
| 1526 | @kindex set mipsfpu |
| 1527 | @kindex show mipsfpu |
| 1528 | @cindex MIPS remote floating point |
| 1529 | @cindex floating point, MIPS remote |
| 1530 | If your target board does not support the MIPS floating point |
| 1531 | coprocessor, you should use the command @samp{set mipsfpu none} (if you |
| 1532 | need this, you may wish to put the command in your @value{GDBINIT} |
| 1533 | file). This tells @value{GDBN} how to find the return value of |
| 1534 | functions which return floating point values. It also allows |
| 1535 | @value{GDBN} to avoid saving the floating point registers when calling |
| 1536 | functions on the board. If you are using a floating point coprocessor |
| 1537 | with only single precision floating point support, as on the @sc{r4650} |
| 1538 | processor, use the command @samp{set mipsfpu single}. The default |
| 1539 | double precision floating point coprocessor may be selected using |
| 1540 | @samp{set mipsfpu double}. |
| 1541 | |
| 1542 | In previous versions the only choices were double precision or no |
| 1543 | floating point, so @samp{set mipsfpu on} will select double precision |
| 1544 | and @samp{set mipsfpu off} will select no floating point. |
| 1545 | |
| 1546 | As usual, you can inquire about the @code{mipsfpu} variable with |
| 1547 | @samp{show mipsfpu}. |
| 1548 | |
| 1549 | @item set remotedebug @var{n} |
| 1550 | @itemx show remotedebug |
| 1551 | @kindex set remotedebug |
| 1552 | @kindex show remotedebug |
| 1553 | @cindex @code{remotedebug}, MIPS protocol |
| 1554 | @cindex MIPS @code{remotedebug} protocol |
| 1555 | @c FIXME! For this to be useful, you must know something about the MIPS |
| 1556 | @c FIXME...protocol. Where is it described? |
| 1557 | You can see some debugging information about communications with the board |
| 1558 | by setting the @code{remotedebug} variable. If you set it to @code{1} using |
| 1559 | @samp{set remotedebug 1}, every packet is displayed. If you set it |
| 1560 | to @code{2}, every character is displayed. You can check the current value |
| 1561 | at any time with the command @samp{show remotedebug}. |
| 1562 | |
| 1563 | @item set timeout @var{seconds} |
| 1564 | @itemx set retransmit-timeout @var{seconds} |
| 1565 | @itemx show timeout |
| 1566 | @itemx show retransmit-timeout |
| 1567 | @cindex @code{timeout}, MIPS protocol |
| 1568 | @cindex @code{retransmit-timeout}, MIPS protocol |
| 1569 | @kindex set timeout |
| 1570 | @kindex show timeout |
| 1571 | @kindex set retransmit-timeout |
| 1572 | @kindex show retransmit-timeout |
| 1573 | You can control the timeout used while waiting for a packet, in the MIPS |
| 1574 | remote protocol, with the @code{set timeout @var{seconds}} command. The |
| 1575 | default is 5 seconds. Similarly, you can control the timeout used while |
| 1576 | waiting for an acknowledgement of a packet with the @code{set |
| 1577 | retransmit-timeout @var{seconds}} command. The default is 3 seconds. |
| 1578 | You can inspect both values with @code{show timeout} and @code{show |
| 1579 | retransmit-timeout}. (These commands are @emph{only} available when |
| 1580 | @value{GDBN} is configured for @samp{--target=mips-idt-ecoff}.) |
| 1581 | |
| 1582 | The timeout set by @code{set timeout} does not apply when @value{GDBN} |
| 1583 | is waiting for your program to stop. In that case, @value{GDBN} waits |
| 1584 | forever because it has no way of knowing how long the program is going |
| 1585 | to run before stopping. |
| 1586 | @end table |
| 1587 | |
| 1588 | @node Simulator |
| 1589 | @subsection Simulated CPU target |
| 1590 | |
| 1591 | @cindex simulator |
| 1592 | @cindex simulator, Z8000 |
| 1593 | @cindex Z8000 simulator |
| 1594 | @cindex simulator, H8/300 or H8/500 |
| 1595 | @cindex H8/300 or H8/500 simulator |
| 1596 | @cindex simulator, Hitachi SH |
| 1597 | @cindex Hitachi SH simulator |
| 1598 | @cindex CPU simulator |
| 1599 | For some configurations, @value{GDBN} includes a CPU simulator that you |
| 1600 | can use instead of a hardware CPU to debug your programs. |
| 1601 | Currently, simulators are available for ARM, D10V, D30V, FR30, H8/300, |
| 1602 | H8/500, i960, M32R, MIPS, MN10200, MN10300, PowerPC, SH, Sparc, V850, |
| 1603 | W65, and Z8000. |
| 1604 | |
| 1605 | @cindex simulator, Z8000 |
| 1606 | @cindex Zilog Z8000 simulator |
| 1607 | When configured for debugging Zilog Z8000 targets, @value{GDBN} includes |
| 1608 | a Z8000 simulator. |
| 1609 | |
| 1610 | For the Z8000 family, @samp{target sim} simulates either the Z8002 (the |
| 1611 | unsegmented variant of the Z8000 architecture) or the Z8001 (the |
| 1612 | segmented variant). The simulator recognizes which architecture is |
| 1613 | appropriate by inspecting the object code. |
| 1614 | |
| 1615 | @table @code |
| 1616 | @item target sim @var{args} |
| 1617 | @kindex sim |
| 1618 | @kindex target sim |
| 1619 | Debug programs on a simulated CPU. If the simulator supports setup |
| 1620 | options, specify them via @var{args}. |
| 1621 | @end table |
| 1622 | |
| 1623 | @noindent |
| 1624 | After specifying this target, you can debug programs for the simulated |
| 1625 | CPU in the same style as programs for your host computer; use the |
| 1626 | @code{file} command to load a new program image, the @code{run} command |
| 1627 | to run your program, and so on. |
| 1628 | |
| 1629 | As well as making available all the usual machine registers (see |
| 1630 | @code{info reg}), the Z8000 simulator provides three additional items |
| 1631 | of information as specially named registers: |
| 1632 | |
| 1633 | @table @code |
| 1634 | @item cycles |
| 1635 | Counts clock-ticks in the simulator. |
| 1636 | |
| 1637 | @item insts |
| 1638 | Counts instructions run in the simulator. |
| 1639 | |
| 1640 | @item time |
| 1641 | Execution time in 60ths of a second. |
| 1642 | @end table |
| 1643 | |
| 1644 | You can refer to these values in @value{GDBN} expressions with the usual |
| 1645 | conventions; for example, @w{@samp{b fputc if $cycles>5000}} sets a |
| 1646 | conditional breakpoint that suspends only after at least 5000 |
| 1647 | simulated clock ticks. |
| 1648 | |
| 1649 | @c need to add much more detail about sims! |