Serial Vector Format

Serial Vector Format (SVF) is a file format that contains boundary scan vectors to be sent to an electronic circuit using a JTAG interface. Boundary scan vectors consist of the following data:

• Stimulus data: This is data to be sent to a device or electronic circuit
• Expected response: This is the data the device or circuit is expected to send back if there is no error
• Mask data: Defines which bits in the expected response are valid; other bits of the device's response are unknown and must be ignored when comparing the expected response and the data returned from the circuit
• Additional information on how to send the data (e.g. maximum clock frequency)

The SVF standard was jointly developed by companies Texas Instruments and Teradyne . Control over the format has been handed off to boundary-scan solution provider ASSET InterTech. The most recent revision is Revision E.

SVF files are used to transfer boundary scan data between tools. As an example a VHDL compiler may create an SVF file that is read by a tool for programming CPLDs.

The SVF file is defined as an ASCII file that consists of a set of SVF statements. The maximum number of characters allowed on a line is 256, although one SVF statement can span more than one line. Each statement consists of a command and associated parameters. Each SVF statement is terminated by a semicolon. SVF is not case sensitive. Comments can be inserted into a SVF file after an exclamation point ‘!’ or a pair of slashes ‘//’. Either ‘//’ or ‘!’ will comment out the remainder of the line.

• ENDDR: Specifies default end state for DR scan operations.
• ENDIR: Specifies default end state for IR scan operations.
• FREQUENCY: Specifies maximum test clock frequency for IEEE 1149.1 bus operations.
• HDR: (Header Data Register) Specifies a header pattern that is prepended to the beginning of subsequent DR scan operations.
• HIR: (Header Instruction Register) Specifies a header pattern that is prepended to the beginning of subsequent IR scan operations.
• PIO: (Parallel Input/Output) Specifies a parallel test pattern.
• PIOMAP: (Parallel Input/Output Map) Maps PIO column positions to a logical pin.
• RUNTEST: Forces the IEEE 1149.1 bus to a run state for a specified number of clocks or a specified time period.
• SDR: (Scan Data Register) Performs an IEEE 1149.1 Data Register scan.
• SIR: (Scan Instruction Register) Performs an IEEE 1149.1 Instruction Register scan.
• STATE: Forces the IEEE 1149.1 bus to a specified stable state.
• TDR: (Trailer Data Register) Specifies a trailer pattern that is appended to the end of subsequent DR scan operations.
• TIR: (Trailer Instruction Register) Specifies a trailer pattern that is appended to the end of subsequent IR scan operations.
• TRST: (Test ReSeT) Controls the optional Test Reset line.

• The In-System Configuration Handbook: A Designer's Guide to ISC, Neil G. Jacobson, ISBN 1-4020-7655-X

• Serial Vector Format Specification latest version available - Revision E
• SVF and XSVF File Formats for Xilinx Devices specifies XSVF, a binary version of SVF

• Electronics manufacturing
• Computer file formats