Serial Vector Format

Serial Vector Format (SVF) is a file format designed to enable transfer of boundary scan vectors between tools. This means that the file format is able to store data that is intended to be transferred via a JTAG interface e.g. for programming FPGA or CPLD devices or for IEEE 1149.1-based boundary scan tests. SVF files contain the data to be sent to the electronic circuit or device (so-called stimulus) as well as the data expected as response from the circuit or device. The file may also contain so-called "mask data" that indicates which parts of the data returned should not be compared to the expected response but should be ignored. The 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 March 1999.

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.

SVF Commands

• 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.

References

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

External links

• Serial Vector Format Specification
• SVF and XSVF File Formats for Xilinx Devices specifies XSVF, a binary version of SVF