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One of the original purposes of JTAG was to support boundary scan based hardware testing. Although its primary focus is to support On-Chip Debugging, OpenOCD also includes some boundary scan commands.
The Serial Vector Format, better known as 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.
This issues a JTAG reset (Test-Logic-Reset) and then runs the SVF script from filename. Unless the quiet option is specified, each command is logged before it is executed.
The Xilinx Serial Vector Format, better known as 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.
Important: Not all XSVF commands are supported.
This issues a JTAG reset (Test-Logic-Reset) and then runs the XSVF script from filename. When a tapname is specified, the commands are directed at that TAP. When virt2 is specified, the XRUNTEST command counts are interpreted as TCK cycles instead of microseconds. Unless the quiet option is specified, messages are logged for comments and some retries.
The OpenOCD sources also include two utility scripts for working with XSVF; they are not currently installed after building the software. You may find them useful:
xsvf command; see notes below.
The input format accepts a handful of non-standard extensions. These include three opcodes corresponding to SVF extensions from Lattice Semiconductor (LCOUNT, LDELAY, LDSR), and two opcodes supporting a more accurate translation of SVF (XTRST, XWAITSTATE). If xsvfdump shows a file is using those opcodes, it probably will not be usable with other XSVF tools.
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