@end deffn
@section Transport Configuration
+@cindex Transport
As noted earlier, depending on the version of OpenOCD you use,
and the debug adapter you are using,
several transports may be available to
@end deffn
@subsection JTAG Transport
+@cindex JTAG
JTAG is the original transport supported by OpenOCD, and most
of the OpenOCD commands support it.
JTAG transports expose a chain of one or more Test Access Points (TAPs),
JTAG supports both debugging and boundary scan testing.
Flash programming support is built on top of debug support.
@subsection SWD Transport
+@cindex SWD
+@cindex Serial Wire Debug
SWD (Serial Wire Debug) is an ARM-specific transport which exposes one
Debug Access Point (DAP, which must be explicitly declared.
(SWD uses fewer signal wires than JTAG.)
SWD is debug-oriented, and does not support boundary scan testing.
Flash programming support is built on top of debug support.
(Some processors support both JTAG and SWD.)
+@deffn Command {swd newdap} ...
+Declares a single DAP which uses SWD transport.
+Parameters are currently the same as "jtag newtap" but this is
+expected to change.
+@end deffn
+@deffn Command {swd wcr trn prescale}
+Updates TRN (turnaraound delay) and prescaling.fields of the
+Wire Control Register (WCR).
+No parameters: displays current settings.
+@end deffn
+
@subsection SPI Transport
+@cindex SPI
+@cindex Serial Peripheral Interface
The Serial Peripheral Interface (SPI) is a general purpose transport
which uses four wire signaling. Some processors use it as part of a
solution for flash programming.