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Hi all, I'm new with UVM and I came across a problem. I am working on an AXI RD VIP using UVM and I have the following issue. In the data_phase (the data channel driving) from the MASTER driver, I need to drive the RREADY signal. There are 3 handshake types described in the protocol specifications: valid before ready, ready before valid and ready and valid at the same time. In case of valid before ready, I want to wait a certain number of clock cycles ( delay ) from the time that RVALID asserted and then to assert the RREADY signal. From my understanding, all the delay information should come from the transaction(sequence_item). The problem is that I generate a new transaction (sequence_item) with get_next_item only when I drive the address channel (in address_phase); The data_phase works in parallel with the addr_phase and its independent of the address phase. Also the data_phase needs multiple delay values (one for each data received from DUT, ex. arlen+1) while I only generate one transaction that contains the address channel informations. Code example: task run_phase(uvm_phase phase) fork forever begin ... seq_item_port.get_next_item(req); address_phase(req); seq_item_port.item_done(); end forever begin data_phase(); end endtask : run_phase task address_phase(axi_item item); // Drive the address channel ... endtask : address_phase task data_phase(); // Wait for the rvalid signal while(!vif.rvalid) @(posedge vif.clk); // Insert delay between rvalid assertion and rready assertion repeat(<problem!!!!>) @(posedge vif.clk); rready = 1; ... endtask : data_phase I don't know what variable (sequence_item variable) to set in the <problem!!!> Can anyone give me an advice regarding this problem. I repeat, I want all timing related data to be set from the sequence_item Regards, Adrian

Which is best method to start , randomize and end the sequence among the `uvm_do, start_item, `uvm_create, `uvm_send and the others and why? Please explain.