Jump opcodes control conditional branching in a pattern. Use these opcodes to branch to a specified label when the selected condition is true.

Conceptual Overview

The jump and jump_if opcodes direct the execution flow to a label. The jump opcode does this action unconditionally, while the jump_if opcode does so when the system meets a specific condition. These conditions include the following items:
  • failed
  • matched
  • seqflag
  • trigger
You can also optionally invert the condition with the ! character.

Syntax Reference

Table 1. Syntax Descriptions for Jump Opcodes
Syntax Description
jump(label) Executes the current vector and then executes the vector the label specifies. Execution continues from the vector the label defines.
jump_if([!]failed, label) Jumps when the failed condition is true.
jump_if([!]seqflag, label) Jumps when the specified sequencer flag is set.
jump_if([!]matched, label) Jumps when the matched condition is true.
jump_if([!]trigger, label) Jumps when the specified trigger is asserted.

Parameter Definitions

The following parameters specify conditions or targets for jump instructions. Use these conditions or targets in jump_if opcodes to control execution flow.
  • failed—Indicates any comparison failure in the current pattern burst. The system excludes vectors that you executed within the last 80 cycles or vectors with the match opcode. Use the repeat opcode to implement an 80-cycle delay.
  • label—Any local label within the pattern file or any label exported from another pattern file.
  • matched—Indicates that the vector executed exactly 80 cycles prior matched. Refer to instrument specifications for pipeline latency details when hardware versions change.
  • seqflag—Specifies a sequencer flag parameter.
    Valid values:
    • seqflag0
    • seqflag1
    • seqflag2
    • seqflag3
  • trigger—Specifies a trigger parameter.
    Valid values:
    • trig0
    • trig1
    • trig2
    • trig3
    • Note Use NI-TClk to synchronize instruments when you apply seqflag or trigger across multiple instruments.
    Note See Pattern Responses to Comparisons for more information about synchronizing multiple instruments and about parameters on vectors that span more than one instrument or more than one site.

    Evaluation Differences

    The system evaluates the matched parameter and the !failed parameter differently. Similarly, !matched parameter and the failed parameter have distinct evaluations. For more details, see the descriptions of the matched parameter and failed parameter.

    Special Considerations

    Additional steps are necessary when using the following opcodes or the following parameters.
    • match opcode
    • matched parameter of the jump_if opcode or the exit_loop_if opcode in burst patterns
    • failed parameter of the jump_if opcode or the exit_loop_if opcode in burst patterns

    Synchronization Requirements for Comparison Results

    If a pattern bursts across multiple synchronized digital pattern instruments, enable each instrument to process comparison results. Use Enable Match… for each synchronized instrument to process comparison results. Use one of the following options to enable comparison result processing for synchronized instruments.
    • niDigital Enable Match Fail Combination VI
    • EnableMatchFailCombination .NET method
    • niDigital_EnableMatchFailCombination C function
    You must also use the NI-Sync driver and a PXIe-6674T timing and synchronization instrument. These tools combine comparison results across instruments that are synchronized with NI-TClk.

    Branching on failed with an 80‑Cycle Pipeline Delay

    // Assume that no failed comparisons have occurred before this vector.

sample_timeset L;

// This vector will not fail even if the previous vector evaluates to false
// because it does not meet the required minimum number of cycles to wait.
jump_if(failed, error)      sample_timeset X;

continue: repeat(78)        sample_timeset X;

// Pipeline delay must be at least 80 cycles after the last failure.
// If it is less than 80, the !failed condition is always true.
// If it is 80 or greater, the !failed condition reflects the result of
// the comparison.

// The jump to the end label executes if the !failed condition is true.
// If the failed condition is asserted because of a comparison 80 cycles ago,
// the pattern does not branch to the end label and continues to the next
// vector with the error label.
jump_if(!failed, end)       sample_timeset X;

error: halt                 sample_timeset X;
end: halt                   sample_timeset X;