Evaluate properties¶

Use property when the question is about a Boolean condition rather than a raw signal table. --on selects when to check, --eval defines the condition, and --capture selects which results to keep.

When did a condition first match?¶

Use --capture match --max 1:

$ wavepeek property --waves dump.fst \
    --scope tb.dut.cpu \
    --on 'posedge clk iff reset_n' \
    --eval "state == 4'h7" \
    --capture match --max 1
@840ns sample@839ns match

A truncation warning after the row means more matches exist. It does not invalidate the first match.

Did a condition ever become true or false?¶

The default switch capture reports both transitions of the Boolean result:

$ wavepeek property --waves dump.fst \
    --scope tb.dut \
    --from 100ns --to 300ns \
    --on 'posedge clk' \
    --eval 'req && !ack'
@140ns sample@139ns assert
@180ns sample@179ns deassert

Use --capture assert or --capture deassert when only one transition matters. Use --capture match when every selected event where the expression is true should produce a row.

How many handshakes occurred?¶

Count all matching clock events without printing them:

$ wavepeek property --waves dump.fst \
    --scope tb.dut.bus \
    --on 'posedge clk iff reset_n' \
    --eval 'valid && ready' \
    --capture match --summary --max unlimited
complete: true
returned: 37
limit: null
total: 37

Use --max unlimited for an exact total. With a numeric limit, total can remain unknown if the scan stops early.

Which requests targeted this address?¶

Predicates can combine a handshake with payload conditions:

wavepeek property --waves dump.fst \
  --scope tb.dut.requester \
  --on 'posedge clk iff reset_n' \
  --eval "req_valid && req_ready && (req_addr == 32'h00001000)" \
  --capture match

This reports the matching timestamps but not the request payload. Use extract generic when payload values are needed in the same row.

What if the condition is asynchronous?¶

Use native sampling for change-driven checks:

wavepeek property --waves dump.fst \
  --scope tb.dut \
  --on '*' --sample-mode native \
  --eval "error_code != 8'h00" \
  --capture assert

See Boolean conditions for common expression forms and Clocks and sampling before comparing a clocked property with RTL or SVA behavior.