bash$ openocd --help --help | -h display this help --version | -v display OpenOCD version --file | -f use configuration file <name> --search | -s dir to search for config files and scripts --debug | -d set debug level <0-3> --log_output | -l redirect log output to file <name> --command | -c run <command> --pipe | -p use pipes when talking to gdb
By default OpenOCD reads the file configuration file openocd.cfg in the current directory. To specify a different (or multiple) configuration file, you can use the “-f” option. For example:
openocd -f config1.cfg -f config2.cfg -f config3.cfg
OpenOCD starts by processing the configuration commands provided on the command line or in openocd.cfg. See Configuration Stage. At the end of the configuration stage it verifies the JTAG scan chain defined using those commands; your configuration should ensure that this always succeeds. Normally, OpenOCD then starts running as a daemon. Alternatively, commands may be used to terminate the configuration stage early, perform work (such as updating some flash memory), and then shut down without acting as a daemon.
Once OpenOCD starts running as a daemon, it waits for connections from clients (Telnet, GDB, Other) and processes the commands issued through those channels.
If you are having problems, you can enable internal debug messages via the “-d” option.
Also it is possible to interleave JIM-Tcl commands w/config scripts using the -c command line switch.
To enable debug output (when reporting problems or working on OpenOCD itself), use the -d command line switch. This sets the debug_level to "3", outputting the most information, including debug messages. The default setting is "2", outputting only informational messages, warnings and errors. You can also change this setting from within a telnet or gdb session using debug_level <n> (see debug_level).
You can redirect all output from the daemon to a file using the -l <logfile> switch.
Search paths for config/script files can be added to OpenOCD by using the -s <search> switch. The current directory and the OpenOCD target library is in the search path by default.
For details on the -p option. See Connecting to GDB.
Note! OpenOCD will launch the GDB & telnet server even if it can not establish a connection with the target. In general, it is possible for the JTAG controller to be unresponsive until the target is set up correctly via e.g. GDB monitor commands in a GDB init script.