diff options
| -rw-r--r-- | doc/openocd.texi | 51 |
1 files changed, 23 insertions, 28 deletions
diff --git a/doc/openocd.texi b/doc/openocd.texi index 7f73a4c3..3a396b1e 100644 --- a/doc/openocd.texi +++ b/doc/openocd.texi @@ -238,27 +238,11 @@ That said, the OpenOCD developers would also like you to follow a few suggestions: @enumerate -@item @b{Send patches, including config files, upstream.} -@item @b{Always build with printer ports enabled.} -@item @b{Try to use LIBFTDI + LIBUSB where possible. You cover more bases.} +@item Send patches, including config files, upstream. +@item Always build with printer ports enabled. +@item Use libftdi + libusb for FT2232 support. @end enumerate -@itemize @bullet -@item @b{Why YES to LIBFTDI + LIBUSB?} -@itemize @bullet -@item @b{LESS} work - libusb perhaps already there -@item @b{LESS} work - identical code, multiple platforms -@item @b{MORE} dongles are supported -@item @b{MORE} platforms are supported -@item @b{MORE} complete solution -@end itemize -@item @b{Why not LIBFTDI + LIBUSB} (i.e.: ftd2xx instead)? -@itemize @bullet -@item @b{LESS} speed - some say it is slower -@item @b{LESS} complex to distribute (external dependencies) -@end itemize -@end itemize - @section Building From Source You can download the current SVN version with an SVN client of your choice from the @@ -297,16 +281,21 @@ a FTDI FT2232 based interface: @itemize @bullet @item @b{ftdi2232} libftdi (@uref{http://www.intra2net.com/opensource/ftdi/}) -@item @b{ftd2xx} libftd2xx (@uref{http://www.ftdichip.com/Drivers/D2XX.htm}) -@item When using the Amontec JTAGkey, you have to get the drivers from the Amontec -homepage (@uref{http://www.amontec.com}). The JTAGkey uses a non-standard VID/PID. +@item @b{ftd2xx} libftd2xx (@uref{http://www.ftdichip.com/Drivers/D2XX.htm}), +or the Amontec version (from @uref{http://www.amontec.com}), +for easier support of JTAGkey's vendor and product IDs. @end itemize libftdi is supported under Windows. Do not use versions earlier than 0.14. +To use the newer FT2232H chips, supporting RTCK and USB high speed (480 Mbps), +you need libftdi version 0.16 or newer. -In general, the D2XX driver provides superior performance (several times as fast), -but has the draw-back of being binary-only - though that isn't that bad, as it isn't -a kernel module, only a user space library. +Some people say that FTDI's libftd2xx code provides better performance. +However, it is binary-only, while OpenOCD is licenced according +to GNU GPLv2 without any exceptions. +That means that @emph{distributing} copies of OpenOCD built with +the FTDI code would violate the OpenOCD licensing terms. +You may, however, build such copies for personal use. To build OpenOCD (on both Linux and Cygwin), use the following commands: @@ -354,9 +343,12 @@ should be included (among other things): @item @option{--enable-gw16012} - Enable building support for the Gateworks GW16012 JTAG programmer. @item -@option{--enable-ft2232_ftd2xx} - Numerous USB type ARM JTAG dongles use the FT2232C chip from this FTDICHIP.COM chip (closed source). +@option{--enable-ft2232_ftd2xx} - Support FT2232-family chips using +the closed-source library from FTDICHIP.COM +(result not for re-distribution). @item -@option{--enable-ft2232_libftdi} - An open source (free) alternative to FTDICHIP.COM ftd2xx solution (Linux, MacOS, Cygwin). +@option{--enable-ft2232_libftdi} - Support FT2232-family chips using +a GPL'd ft2232 support library (result OK for re-distribution). @item @option{--with-ftd2xx-win32-zipdir=PATH} - If using FTDICHIP.COM ft2232c driver, give the directory where the Win32 FTDICHIP.COM 'CDM' driver zip file was unpacked. @@ -399,7 +391,10 @@ use both the @option{--enable-parport} AND the @option{--enable-parport_giveio} There are 2 methods of using the FTD2232, either (1) using the FTDICHIP.COM closed source driver, or (2) the open (and free) driver -libftdi. Some claim the (closed) FTDICHIP.COM solution is faster. +libftdi. Some claim the (closed) FTDICHIP.COM solution is faster, +which is the motivation for supporting it even though its licensing +restricts it to non-redistributable OpenOCD binaries, and it is +not available for all operating systems used with OpenOCD. The FTDICHIP drivers come as either a (win32) ZIP file, or a (Linux) TAR.GZ file. You must unpack them ``some where'' convient. As of this |