Serial Vector Format is a vector exchange format, designed to enable transfer of boundary scan

Boundary scan

Boundary scan is a method for testing interconnects on printed circuit boards or sub-blocks inside an integrated circuit. Boundary scan is also widely used as a debugging method to watch integrated circuit pin states, measure voltage, or analyze sub-blocks inside an integrated circuit.The Joint...

 vectors between tools. SVF is expressing test patterns that represent the stimulus, expected response, and mask data for IEEE 1149.1-based (JTAG

JTAG

Joint Test Action Group is the common name for what was later standardized as the IEEE 1149.1 Standard Test Access Port and Boundary-Scan Architecture. It was initially devised for testing printed circuit boards using boundary scan and is still widely used for this application.Today JTAG is also...

) tests. The standard was jointly developed by companies Texas Instruments

Texas Instruments

Texas Instruments Inc. , widely known as TI, is an American company based in Dallas, Texas, United States, which develops and commercializes semiconductor and computer technology...

and Teradyne

Teradyne

Teradyne , a US company, is a supplier of automatic test equipment . The company's divisions Semiconductor Test and Systems Test Group, are organized by the products they develop and deliver.-History:...

. 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.

External links

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