Timesets

A timeset defines the period and pin behavior for one tester cycle. Wavetables contain wave groups, waves map symbols to pins, and events describe actions at specific points in the period.

Simple Timesets

Create a timeset in timing.py:

Timeset("simple", default_period=10)

Periods are resolved when a pattern is generated. Keep units consistent with the application and tester timing conventions.

Wavetables And Waves

Build explicit waveforms when pins need drive or compare edges:

t = Timeset("functional", default_period=40)
wtbl = t.add_wavetable("default")
ports = wtbl.add_waves("Ports")

drive_high = ports.add_wave("1")
drive_high.apply_to("porta", "portb")
drive_high.push_event(
    at="period*0.25",
    unit="ns",
    action=drive_high.DriveHigh,
)

compare_high = ports.add_wave("H")
compare_high.apply_to("porta", "portb")
compare_high.push_event(
    at="period*0.10",
    unit="ns",
    action=compare_high.VerifyHigh,
)

The at expression may reference period. The tester backend resolves the semantic action into its native edge and symbol representation.

Clock Waves

A clock wave normally contains multiple events in one cycle:

clocks = wtbl.add_waves("Clocks")
clock = clocks.add_wave("1")
clock.apply_to("clk")
clock.push_event(at=0, unit="ns", action=clock.DriveHigh)
clock.push_event(at="period/2", unit="ns", action=clock.DriveLow)

Symbol Maps

Timesets can override the symbols emitted for model actions:

t.symbol_map["1"] = "0"
t.symbol_map["0"] = "1"
t.symbol_map[origen.pins.PinActions.VerifyHigh()] = "L"
t.symbol_map[origen.pins.PinActions.VerifyLow()] = "H"

Use overrides sparingly and document why the tester or protocol requires them.

Tester Translation

The same timeset model can feed different tester backends, but not every tester supports every edge or expression. Consult the tester-specific guide and keep approved output for each supported target.

Testing

Test period evaluation, pin applicability, event ordering, symbol mappings, and generated timing resources. Include boundary cases such as events at time zero, half-period expressions, and incompatible drive/compare combinations.