ovm_sequence_item

The constructor method for ovm_sequence_item.  The sequencer and parent_sequence may be specified in the constructor, or directly using ovm_sequence_item methods.

private

Get_sequence_id is an internal method that is not intended for user code.  The sequence_id is not a simple integer.  The get_transaction_id is meant for users to identify specific transactions.

These methods allow access to the sequence_item sequence and transaction IDs. get_transaction_id and set_transaction_id are methods on the ovm_transaction base_class.  These IDs are used to identify sequences to the sequencer, to route responses back to the sequence that issued a request, and to uniquely identify transactions.

The sequence_id is assigned automatically by a sequencer when a sequence initiates communication through any sequencer calls (i.e.  `ovm_do_xxx, wait_for_grant).  A sequence_id will remain unique for this sequence until it ends or it is killed.  However, a single sequence may have multiple valid sequence ids at any point in time.  Should a sequence start again after it has ended, it will be given a new unique sequence_id.

The transaction_id is assigned automatically by the sequence each time a transaction is sent to the sequencer with the transaction_id in its default (-1) value.  If the user sets the transaction_id to any non-default value, that value will be maintained.

Responses are routed back to this sequences based on sequence_id.  The sequence may use the transaction_id to correlate responses with their requests.

These methods are used to set and get the status of the use_sequence_info bit.  Use_sequence_info controls whether the sequence information (sequencer, parent_sequence, sequence_id, etc.) is printed, copied, or recorded.  When use_sequence_info is the default value of 0, then the sequence information is not used.  When use_sequence_info is set to 1, the sequence information will be used in printing and copying.

Copies the sequence_id and transaction_id from the referenced item into the calling item.  This routine should always be used by drivers to initialize responses for future compatibility.

These routines set and get the reference to the sequencer to which this sequence_item communicates.

Sets the parent sequence of this sequence_item.  This is used to identify the source sequence of a sequence_item.

Returns a reference to the parent sequence of any sequence on which this method was called.  If this is a parent sequence, the method returns null.

The depth of any sequence is calculated automatically.  However, the user may use set_depth to specify the depth of a particular sequence.  This method will override the automatically calculated depth, even if it is incorrect.

Returns the depth of a sequence from it’s parent.  A parent sequence will have a depth of 1, it’s child will have a depth of 2, and it’s grandchild will have a depth of 3.

This function may be called on any sequence_item or sequence.  It will return 1 for items and 0 for sequences (which derive from this class).

start_item and finish_item together will initiate operation of either a sequence_item or sequence object.  If the object has not been initiated using create_item, then start_item will be initialized in start_item to use the default sequencer specified by m_sequencer.  Randomization may be done between start_item and finish_item to ensure late generation

finish_item, together with start_item together will initiate operation of either a sequence_item or sequence object.  Finish_item must be called after start_item with no delays or delta-cycles.  Randomization, or other functions may be called between the start_item and finish_item calls.

Provides the name of the root sequence (the top-most parent sequence).

Provides a reference to the root sequence (the top-most parent sequence).

Provides a string of names of each sequence in the full hierarchical path.  A “.” is used as the separator between each sequence.