@menu
* About:: About OpenOCD
-* Developers:: OpenOCD Developers
-* JTAG Hardware Dongles:: JTAG Hardware Dongles
+* Developers:: OpenOCD Developer Resources
+* Debug Adapter Hardware:: Debug Adapter Hardware
* About JIM-Tcl:: About JIM-Tcl
* Running:: Running OpenOCD
* OpenOCD Project Setup:: OpenOCD Project Setup
* Config File Guidelines:: Config File Guidelines
* Daemon Configuration:: Daemon Configuration
-* Interface - Dongle Configuration:: Interface - Dongle Configuration
+* Debug Adapter Configuration:: Debug Adapter Configuration
* Reset Configuration:: Reset Configuration
* TAP Declaration:: TAP Declaration
* CPU Configuration:: CPU Configuration
in-system programming and boundary-scan testing for embedded target
devices.
-@b{JTAG:} OpenOCD uses a ``hardware interface dongle'' to communicate
-with the JTAG (IEEE 1149.1) compliant TAPs on your target board.
+It does so with the assistance of a @dfn{debug adapter}, which is
+a small hardware module which helps provide the right kind of
+electrical signaling to the target being debugged. These are
+required since the debug host (on which OpenOCD runs) won't
+usually have native support for such signaling, or the connector
+needed to hook up to the target.
+
+Such debug adapters support one or more @dfn{transport} protocols,
+each of which involves different electrical signaling (and uses
+different messaging protocols on top of that signaling). There
+are many types of debug adapter, and little uniformity in what
+they are called. (There are also product naming differences.)
+
+These adapters are sometimes packaged as discrete dongles. which
+may generically be called @dfn{hardware interface dongles}.
+Some development boards also integrate them directly, which may
+let the development board can be directly connected to the debug
+host over USB (and sometimes also to power it over USB).
+
+For example, a @dfn{JTAG Adapter} supports JTAG
+signaling, and is used to communicate
+with JTAG (IEEE 1149.1) compliant TAPs on your target board.
A @dfn{TAP} is a ``Test Access Port'', a module which processes
special instructions and data. TAPs are daisy-chained within and
-between chips and boards.
+between chips and boards. JTAG supports debugging and boundary
+scan operations.
+
+There are also @dfn{SWD Adapters} that support Serial Wire Debug (SWD)
+signaling to communicate with some newer ARM cores, as well as debug
+adapters which support both JTAG and SWD transports. SWD only supports
+debugging, whereas JTAG also supports boundary scan operations.
+
+For some chips, there are also @dfn{Programming Adapters} supporting
+special transports used only to write code to flash memory, without
+support for on-chip debugging or boundary scan.
+(At this writing, OpenOCD does not support such non-debug adapters.)
+
@b{Dongles:} OpenOCD currently supports many types of hardware dongles: USB
based, parallel port based, and other standalone boxes that run
-OpenOCD internally. @xref{JTAG Hardware Dongles}.
+OpenOCD internally. @xref{Debug Adapter Hardware}.
@b{GDB Debug:} It allows ARM7 (ARM7TDMI and ARM720t), ARM9 (ARM920T,
ARM922T, ARM926EJ--S, ARM966E--S), XScale (PXA25x, IXP42x) and
The @file{PATCHES.txt} file contains basic information about how
to prepare patches.
+@section OpenOCD Bug Database
+
+During the 0.4.x release cycle the OpenOCD project team began
+using Trac for its bug database:
+
+@uref{https://sourceforge.net/apps/trac/openocd}
+
-@node JTAG Hardware Dongles
-@chapter JTAG Hardware Dongles
+@node Debug Adapter Hardware
+@chapter Debug Adapter Hardware
@cindex dongles
@cindex FTDI
@cindex wiggler
Defined: @b{dongle}: A small device that plugins into a computer and serves as
an adapter .... [snip]
-In the OpenOCD case, this generally refers to @b{a small adapater} one
-attaches to your computer via USB or the Parallel Printer Port. The
-execption being the Zylin ZY1000 which is a small box you attach via
+In the OpenOCD case, this generally refers to @b{a small adapter} that
+attaches to your computer via USB or the Parallel Printer Port. One
+exception is the Zylin ZY1000, packaged as a small box you attach via
an ethernet cable. The Zylin ZY1000 has the advantage that it does not
require any drivers to be installed on the developer PC. It also has
a built in web interface. It supports RTCK/RCLK or adaptive clocking
There are several things you should keep in mind when choosing a dongle.
@enumerate
+@item @b{Transport} Does it support the kind of communication that you need?
+OpenOCD focusses mostly on JTAG. Your version may also support
+other ways to communicate with target devices.
@item @b{Voltage} What voltage is your target - 1.8, 2.8, 3.3, or 5V?
Does your dongle support it? You might need a level converter.
@item @b{Pinout} What pinout does your target board use?
wires, or an "octopus" connector, to convert pinouts.
@item @b{Connection} Does your computer have the USB, printer, or
Ethernet port needed?
-@item @b{RTCK} Do you require RTCK? Also known as ``adaptive clocking''
+@item @b{RTCK} Do you expect to use it with ARM chips and boards with
+RTCK support? Also known as ``adaptive clocking''
@end enumerate
@section Stand alone Systems
known as the FTDI FT2232; this is a USB full speed (12 Mbps) chip.
See: @url{http://www.ftdichip.com} for more information.
In summer 2009, USB high speed (480 Mbps) versions of these FTDI
-chips are starting to become available in JTAG adapters.
+chips are starting to become available in JTAG adapters. (Adapters
+using those high speed FT2232H chips may support adaptive clocking.)
+
+The FT2232 chips are flexible enough to support some other
+transport options, such as SWD or the SPI variants used to
+program some chips. They have two communications channels,
+and one can be used for a UART adapter at the same time the
+other one is used to provide a debug adapter.
+
+Also, some development boards integrate an FT2232 chip to serve as
+a built-in low coast debug adapter and usb-to-serial solution.
@itemize @bullet
@item @b{usbjtag}
@* See: @url{http://www.luminarymicro.com} - The Stellaris eval boards
bundle FT2232-based JTAG and SWD support, which can be used to debug
the Stellaris chips. Using separate JTAG adapters is optional.
-These boards can also be used as JTAG adapters to other target boards,
-disabling the Stellaris chip.
+These boards can also be used in a "pass through" mode as JTAG adapters
+to other target boards, disabling the Stellaris chip.
@item @b{Luminary ICDI}
@* See: @url{http://www.luminarymicro.com} - Luminary In-Circuit Debug
-Interface (ICDI) Boards are included in Stellaris LM3S9B90 and LM3S9B92
+Interface (ICDI) Boards are included in Stellaris LM3S9B9x
Evaluation Kits. Like the non-detachable FT2232 support on the other
Stellaris eval boards, they can be used to debug other target boards.
@item @b{olimex-jtag}
@item @b{ARM-JTAG-EW}
@* Link: @url{http://www.olimex.com/dev/arm-jtag-ew.html}
+
+@item @b{Buspirate}
+@* Link: @url{http://dangerousprototypes.com/bus-pirate-manual/}
@end itemize
@section IBM PC Parallel Printer Port Based
@cindex logfile
@cindex directory search
+Properly installing OpenOCD sets up your operating system to grant it access
+to the debug adapters. On Linux, this usually involves installing a file
+in @file{/etc/udev/rules.d,} so OpenOCD has permissions. MS-Windows needs
+complex and confusing driver configuration for every peripheral. Such issues
+are unique to each operating system, and are not detailed in this User's Guide.
+
+Then later you will invoke the OpenOCD server, with various options to
+tell it how each debug session should work.
The @option{--help} option shows:
@verbatim
bash$ openocd --help
@end enumerate
The first found file with a matching file name will be used.
+@quotation Note
+Don't try to use configuration script names or paths which
+include the "#" character. That character begins Tcl comments.
+@end quotation
+
@section Simple setup, no customization
In the best case, you can use two scripts from one of the script
own subdirectory in the @file{scripts} directory:
@enumerate
-@item @b{interface} -- one for each kind of JTAG adapter/dongle
+@item @b{interface} -- one for each different debug adapter;
@item @b{board} -- one for each different board
@item @b{target} -- the chips which integrate CPUs and other JTAG TAPs
@end enumerate
@item Maybe you don't know yet what your board looks like to JTAG.
Once you know the @file{interface.cfg} file to use, you may
need help from OpenOCD to discover what's on the board.
-Once you find the TAPs, you can just search for appropriate
+Once you find the JTAG TAPs, you can just search for appropriate
+target and board
configuration files ... or write your own, from the bottom up.
@xref{Autoprobing}.
@item
You may may need to write some C code.
It may be as simple as a supporting a new ft2232 or parport
-based dongle; a bit more involved, like a NAND or NOR flash
+based adapter; a bit more involved, like a NAND or NOR flash
controller driver; or a big piece of work like supporting
a new chip architecture.
@end itemize
Use them as-is where you can; or as models for new files.
@itemize @bullet
@item @file{interface} ...
-think JTAG Dongle. Files that configure JTAG adapters go here.
+These are for debug adapters.
+Files that configure JTAG adapters go here.
@example
$ ls interface
arm-jtag-ew.cfg hitex_str9-comstick.cfg oocdlink.cfg
source [find interface/FOOBAR.cfg]
@end example
-A preconfigured interface file should exist for every interface in use
-today, that said, perhaps some interfaces have only been used by the
-sole developer who created it.
+A preconfigured interface file should exist for every debug adapter
+in use today with OpenOCD.
+That said, perhaps some of these config files
+have only been used by the developer who created it.
A separate chapter gives information about how to set these up.
-@xref{Interface - Dongle Configuration}.
-Read the OpenOCD source code if you have a new kind of hardware interface
+@xref{Debug Adapter Configuration}.
+Read the OpenOCD source code (and Developer's GUide)
+if you have a new kind of hardware interface
and need to provide a driver for it.
@section Board Config Files
solution just avoids using that instruction with JTAG debuggers.
@end quotation
-If the board supports adaptive clocking, use the @command{jtag_rclk}
+If both the chip and the board support adaptive clocking,
+use the @command{jtag_rclk}
command, in case your board is used with JTAG adapter which
-also supports it. Otherwise use @command{jtag_khz}.
+also supports it. Otherwise use @command{adapter_khz}.
Set the slow rate at the beginning of the reset sequence,
and the faster rate as soon as the clocks are at full speed.
@end example
@end deffn
-@node Interface - Dongle Configuration
-@chapter Interface - Dongle Configuration
+@node Debug Adapter Configuration
+@chapter Debug Adapter Configuration
@cindex config file, interface
@cindex interface config file
-JTAG Adapters/Interfaces/Dongles are normally configured
+Correctly installing OpenOCD includes making your operating system give
+OpenOCD access to debug adapters. Once that has been done, Tcl commands
+are used to select which one is used, and to configure how it is used.
+
+@quotation Note
+Because OpenOCD started out with a focus purely on JTAG, you may find
+places where it wrongly presumes JTAG is the only transport protocol
+in use. Be aware that recent versions of OpenOCD are removing that
+limitation. JTAG remains more functional than most other transports.
+Other transports do not support boundary scan operations, or may be
+specific to a given chip vendor. Some might be usable only for
+programming flash memory, instead of also for debugging.
+@end quotation
+
+Debug Adapters/Interfaces/Dongles are normally configured
through commands in an interface configuration
file which is sourced by your @file{openocd.cfg} file, or
through a command line @option{-f interface/....cfg} option.
@section Interface Configuration
-The interface command tells OpenOCD what type of JTAG dongle you are
-using. Depending on the type of dongle, you may need to have one or
-more additional commands.
+The interface command tells OpenOCD what type of debug adapter you are
+using. Depending on the type of adapter, you may need to use one or
+more additional commands to further identify or configure the adapter.
@deffn {Config Command} {interface} name
Use the interface driver @var{name} to connect to the
@item @b{olimex-jtag} Olimex ARM-USB-OCD and ARM-USB-Tiny
@item @b{oocdlink} OOCDLink
@c oocdlink ~= jtagkey_prototype_v1
+@item @b{redbee-econotag} Integrated with a Redbee development board.
+@item @b{redbee-usb} Integrated with a Redbee USB-stick development board.
@item @b{sheevaplug} Marvell Sheevaplug development kit
@item @b{signalyzer} Xverve Signalyzer
@item @b{stm32stick} Hitex STM32 Performance Stick
@deffn Command {parport_toggling_time} [nanoseconds]
Displays how many nanoseconds the hardware needs to toggle TCK;
the parport driver uses this value to obey the
-@command{jtag_khz} configuration.
+@command{adapter_khz} configuration.
When the optional @var{nanoseconds} parameter is given,
that setting is changed before displaying the current value.
oscilloscope, follow the procedure below:
@example
> parport_toggling_time 1000
-> jtag_khz 500
+> adapter_khz 500
@end example
This sets the maximum JTAG clock speed of the hardware, but
the actual speed probably deviates from the requested 500 kHz.
@example
> parport_toggling_time <measured nanoseconds>
@end example
-Now the clock speed will be a better match for @command{jtag_khz rate}
+Now the clock speed will be a better match for @command{adapter_khz rate}
commands given in OpenOCD scripts and event handlers.
You can do something similar with many digital multimeters, but note
that you'll probably need to run the clock continuously for several
seconds before it decides what clock rate to show. Adjust the
toggling time up or down until the measured clock rate is a good
-match for the jtag_khz rate you specified; be conservative.
+match for the adapter_khz rate you specified; be conservative.
@end quotation
@end deffn
may not be the fastest solution.
@b{NOTE:} Script writers should consider using @command{jtag_rclk}
-instead of @command{jtag_khz}.
+instead of @command{adapter_khz}, but only for (ARM) cores and boards
+which support adaptive clocking.
-@deffn {Command} jtag_khz max_speed_kHz
+@deffn {Command} adapter_khz max_speed_kHz
A non-zero speed is in KHZ. Hence: 3000 is 3mhz.
JTAG interfaces usually support a limited number of
speeds. The speed actually used won't be faster
requirements that all reset pulses last for at least a
certain amount of time; and reset buttons commonly have
hardware debouncing.
-Use the @command{jtag_nsrst_delay} and @command{jtag_ntrst_delay}
+Use the @command{adapter_nsrst_delay} and @command{jtag_ntrst_delay}
commands to say when extra delays are needed.
@item @emph{Drive type} ... Reset lines often have a pullup
allowing it to be deasserted.
@end deffn
-@deffn {Command} jtag_nsrst_delay milliseconds
+@deffn {Command} adapter_nsrst_delay milliseconds
How long (in milliseconds) OpenOCD should wait after deasserting
nSRST (active-low system reset) before starting new JTAG operations.
When a board has a reset button connected to SRST line it will
before @command{reset_init} is called.
This is the most robust place to use @command{jtag_rclk}
-or @command{jtag_khz} to switch to a low JTAG clock rate,
+or @command{adapter_khz} to switch to a low JTAG clock rate,
when reset disables PLLs needed to use a fast clock.
@ignore
@item @b{reset-wait-pos}
@end example
@end deffn
+@deffn Command {stellaris recover bank_id}
+Performs the @emph{Recovering a "Locked" Device} procedure to
+restore the flash specified by @var{bank_id} and its associated
+nonvolatile registers to their factory default values (erased).
+This is the only way to remove flash protection or re-enable
+debugging if that capability has been disabled.
+
+Note that the final "power cycle the chip" step in this procedure
+must be performed by hand, since OpenOCD can't do it.
+@quotation Warning
+if more than one Stellaris chip is connected, the procedure is
+applied to all of them.
+@end quotation
+@end deffn
+
@deffn {Flash Driver} stm32x
All members of the STM32 microcontroller family from ST Microelectronics
include internal flash and use ARM Cortex M3 cores.
core mode if necessary.
@end deffn
+@deffn Command {arm semihosting} [@option{enable}|@option{disable}]
+@cindex ARM semihosting
+Display status of semihosting, after optionally changing that status.
+
+Semihosting allows for code executing on an ARM target to use the
+I/O facilities on the host computer i.e. the system where OpenOCD
+is running. The target application must be linked against a library
+implementing the ARM semihosting convention that forwards operation
+requests by using a special SVC instruction that is trapped at the
+Supervisor Call vector by OpenOCD.
+@end deffn
+
@section ARMv4 and ARMv5 Architecture
@cindex ARMv4
@cindex ARMv5
speeds, like the 32kHz startup clock of an AT91RM9200.
@end deffn
-@deffn Command {arm7_9 semihosting} [@option{enable}|@option{disable}]
-@cindex ARM semihosting
-Display status of semihosting, after optionally changing that status.
-
-Semihosting allows for code executing on an ARM target to use the
-I/O facilities on the host computer i.e. the system where OpenOCD
-is running. The target application must be linked against a library
-implementing the ARM semihosting convention that forwards operation
-requests by using a special SVC instruction that is trapped at the
-Supervisor Call vector by OpenOCD.
-@end deffn
-
@subsection ARM720T specific commands
@cindex ARM720T
@subsection Cortex-M3 specific commands
@cindex Cortex-M3
-@deffn Command {cortex_m3 disassemble} address [count]
-@cindex disassemble
-Disassembles @var{count} Thumb2 instructions starting at @var{address}.
-If @var{count} is not specified, a single instruction is disassembled.
-@end deffn
-
@deffn Command {cortex_m3 maskisr} (@option{on}|@option{off})
Control masking (disabling) interrupts during target step/resume.
@end deffn
If you're not debugging OpenOCD internals, or bringing up a
new JTAG adapter or a new type of TAP device (like a CPU or
JTAG router), you probably won't need to use these commands.
+In a debug session that doesn't use JTAG for its transport protocol,
+these commands are not available.
@deffn Command {drscan} tap [numbits value]+ [@option{-endstate} tap_state]
Loads the data register of @var{tap} with a series of bit fields
The Serial Vector Format, better known as @dfn{SVF}, is a
way to represent JTAG test patterns in text files.
+In a debug session using JTAG for its transport protocol,
OpenOCD supports running such test files.
@deffn Command {svf} filename [@option{quiet}]
The Xilinx Serial Vector Format, better known as @dfn{XSVF}, is a
binary representation of SVF which is optimized for use with
Xilinx devices.
+In a debug session using JTAG for its transport protocol,
OpenOCD supports running such test files.
@quotation Important
@b{Solution #1 - A special circuit}
In order to make use of this,
-both your CPU and your JTAG dongle must support the RTCK
-feature. Not all dongles support this - keep reading!
+your CPU, board, and JTAG adapter must all support the RTCK
+feature. Not all of them support this; keep reading!
The RTCK ("Return TCK") signal in some ARM chips is used to help with
this problem. ARM has a good description of the problem described at
ARM11 cores use an 8:1 division.
@b{Xilinx rule of thumb} is 1/12 the clock speed.
-Note: Many FTDI2232C based JTAG dongles are limited to 6MHz.
+Note: most full speed FT2232 based JTAG adapters are limited to a
+maximum of 6MHz. The ones using USB high speed chips (FT2232H)
+often support faster clock rates (and adaptive clocking).
You can still debug the 'low power' situations - you just need to
either use a fixed and very slow JTAG clock rate ... or else
@example
# Example: 1.234MHz
-jtag_khz 1234
+adapter_khz 1234
@end example
@* Example: @b{ source [find FILENAME] }
@*Remember the parsing rules
@enumerate
-@item The FIND command is in square brackets.
-@* The FIND command is executed with the parameter FILENAME. It should
-find the full path to the named file. The RESULT is a string, which is
-substituted on the orginal command line.
-@item The command source is executed with the resulting filename.
-@* SOURCE reads a file and executes as a script.
+@item The @command{find} command is in square brackets,
+and is executed with the parameter FILENAME. It should find and return
+the full path to a file with that name; it uses an internal search path.
+The RESULT is a string, which is substituted into the command line in
+place of the bracketed @command{find} command.
+(Don't try to use a FILENAME which includes the "#" character.
+That character begins Tcl comments.)
+@item The @command{source} command is executed with the resulting filename;
+it reads a file and executes as a script.
@end enumerate
@subsection format command
@b{Where:} Generally occurs in numerous places.
Code Review / openocd.git / blobdiff