uvm_reg : do_check for read-only register in UVM (Pre-IEEE) Methodology and BCL Forum Posted May 21, 2012 · Report reply set_compare function void set_compare( uvm_check_e check = UVM_CHECK ) Sets the compare policy during a mirror update. The field value is checked against its mirror only when both the check argument in uvm_reg_block::mirror, uvm_reg::mirror, or uvm_reg_field::mirror and the compare policy for the field is UVM_CHECK. The generator should have a vendor extension for this. But some don't so you manually have to set it: For a field: status_reg.fld0.set_compare(UVM_NO_CHECK); For a register: //this depends on the generator config_reg.data.set_compare(UVM_NO_CHECK); You have to extend the register file that contains these registers and create a derived class that call super.build(). Does the set_compare and then build(); Your generator may have an XML vendor extension for this.