Inherited sequence flow.

virtual sequence extends from uvm_sequence. More recently, they aren't used so much as people got a bit confused - they get called by default with sequence start, but not with `uvm_do. a virtual sequence running on a null sequencer can start other virtual sequences (on this or other sequencers) or other BFM sequences/items (when a real sequencer handle is supplied). Below sequence checks for the signal “a” being high on a given positive edge of the clock. Derive from uvm_sequence base class with a specified data object type Register the sequence with the factory using `uvm_object_utils Set the default sequencer that should execute this sequence Code the main stimulus inside the body () task Virtual sequence will create its sequences and start them. For example, ##2 means 2 clock cycles. So, what might you use pre/post_start for? The 'funky' stuff like grab/lock does probably require a sequencer instance. Simple sequence flow. Running sequences can be controlled by user in the body() task. A uvm_sequence is derived from an uvm_sequence_item; a sequence is parameterized with the type of sequence_item, this defines the type of the item sequence that will send/receive to/from the driver. parent_sequence is often referred to the … Then, you start the sequence on a sequencer, say jb_seqr. priorities should only be in the picture for items. In SVA, clock cycle delays are represented by a “##” sign. METHOD-1: In this method, we will have one base virtual sequence which will hold the handles to different sequencers. A sequence generates a series of sequence_item’s and sends it to the driver via sequencer, Sequence is written by extending the uvm_sequence. thats correct. UVM Sequence. Using set_config_string, user can override the default sequence to any user defined sequence, so that when a sequencer is started, automatically a user defined sequence will be started. virtual task start ( uvm_sequencer_base sequencer, uvm_sequence_base parent_sequence = null, int this_priority = -1, bit call_pre_post = 1 ); Note that you have to always pass the handle to a sequencer which should execute this sequence, whereas the other arguments are optional. In this case, the m_sequencer is set as the jb_env.jb_agent.jb_seqr. sequence s_lib_inst seq_lib(req1,req2); endsequence Sequences with timing relationship. Default sequence is a sequence which will be started automatically. gb_jb_seq. If the signal “a” is not high, then the sequence fails.

start(jb_env.jb_agent.jb_seqr); The start task will set the m_sequencer to the sequencer you specified. Virtual Sequencer extends from uvm_sequencer. Spawned sequence flow. sequence base class virtual class …