How do you raise and drop an objection in a sequence in UVM?

Objection in sequence, objection is raised when it started as a root sequence (a sequence which has no parent sequence), and to drop the objection when it is finished as a root sequence. for a particular phase. so objections were used in the sequence if it is default sequence for a particular phase.

What is the use of raise objection and drop objection in UVM?

The uvm_objection class provides a means for sharing a counter between participating components and sequences. Each participant may “raises” and “drops” objections asynchronously, which increases or decreases the counter value. When the counter reaches zero (from a non-zero value), an “all dropped” condition occurs.

How do you drop all objections in UVM?

The method get_objectors returns you all objectors. Then you can starting to drop them by executing drop_objection. For details see the UVM refernce manual.

Is it advisable to raise objections in Uvm_monitor?

The bigger issue is that you should not be raising and dropping objections in the monitor on a per-transaction basis. Instead, your monitor should just recognize transactions as the occur. If you need to extend the run_phase while the last transaction is in-flight, use phase_ready_to_end() as shown in the UVM Cookbook.

What is the use of objection in UVM?

The primary purpose of the UVM objection is to keep the task-based phases executing, such as run_phase(). Without an objection, UVM ends the phase at the end of the current timeslot.

How do you write UVM sequencer?

Send the request item to the sequencer, which will forward it to the driver….Communication between the Sequence and driver involves below steps,

1. create_item() / create req.
2. wait_for_grant().
3. randomize the req.
4. send the req.
5. wait for item done.
6. get response.

How do you beat UVM test?

UVM recommended solution to delay the end of phase, after all the components have agreed to end the phase with ‘all dropped’ condition, is that the component should raise objection in the phase_ready_to_end method which is executed automatically by UVM once ‘all dropped’ condition is achieved during Run Phase.

What is set drain time in UVM?

Drain time is the period between the last objection to ending a phase, and the actual time the phase is terminated. It usually represents the time it takes for your last set of stimulus (a sequence) to propagate through your design and its output to be captured by a monitor.

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