The driver receives the item and drives it to the DUT through a virtual interface. `uvm_do (Item/Seq) This macro takes seq_item or sequence as argument. Typically configuration classes and data objects are derived from. Refer to “Macros” in the UVM 1. UVM also introduces a bunch of automation mechanisms for implementing print, copy, and compare objects and are defined using the field macros. Overall Implementation To link the RAL with the configuration object, we initialize the registers in every configuration object as handlesThe callback pool is a singleton object that can be accessed by calling uvm_callbacks#(T)::get_global_pool() or uvm_component::get_callback_pool(), where T is the type of the UVM class or component. Class: UVMObjection. The UVM agent is a hierarchical component that groups together other verification components that are dealing with a specific DUT interface. The following methods are also part of the uvm_objection class: clear(): Immediately clears the objection state. The do_pack() is used to pack each propery of the jelly_bean_transaction object using a uvm_packer policy object. UVM TestBench architecture. {"payload":{"allShortcutsEnabled":false,"fileTree":{"distrib/src/reg":{"items":[{"name":"sequences","path":"distrib/src/reg/sequences","contentType":"directory. Gets the data, if any, provided by the last call to trigger. Share. During value or variable assignment to a variable, it is required to assign value or variable of the same data type. The create () method essentially just calls uvm_factory::create_object_by_type (). It does a deep comparison. All the signals listed as the module ports belong to APB specification. 4 UVM Agent. uvm_object - Data structures for testbench configuration; uvm_transaction - Stimulus generation & analysis; The values of the arguments of new method are used to create an entry in a linked list which the UVM uses to locate uvm_components in a pseudo hierarchy, this list is used in the messaging and configuration mechanisms. uvm_object has many common functions like print, copy and compare that are available to all its child classes and can be used out of the box if UVM automation macros are used inside the class definition. I have tried to import it into my project and it seems like the errors were from a wrong compilation order: "uvm_object is not declared", "uvm_barrier is already declared", etc. User classes derived directly from uvm_void inherit none of the UVM functionality, but such classes may be placed. UVM 1. Hence, it is required to have proper synchronization to avoid objects/components being called before they are created, The UVM phasing mechanism serves the purpose of synchronization. The UVM heartbeat can detect simulation hang or lock-up conditions at an early stage rather than the expiry of the global simulation timeout. Length: 4 Days (32 hours) The Universal Verification Methodology (UVM) is the IEEE1800. The left-hand-side `lhs` and right-hand-side `rhs` objects are the two objects used for comparison. TYPE’s constructor, if defined, must have default values on all it arguments. 02. The utility macros help to register each object with the factory. This class provides base functionality for both user-defined RegModel test sequences and “register translation sequences”. There are two branches in the hierarchy : Under uvm_component: Classes that define verification components like driver, monitor and. Simple (non-parameterized) objects use the uvm_object_utils* versions, which do the following: Implements get_type_name, which returns TYPE as a string; Implements create, which allocates an object of type TYPE by calling its constructor with no arguments. Main concepts of UVM (1) • Clear separation of test stimuli (sequences) and test bench –Sequences are treated as ‘transient objects’ and thus independent from the test bench construction and compositionHow to use the UVM configuration facility? Configuration values are set in the uvm_config_db class using the set() method and retrieved using the get() method. Unfortunately this wont work yet because we have to register seq_item as follows `uvm_object_param_utils(seq_item#(A)). This is because in object oriented programming (OOP) extendability doesn't come for free. 1-289-695-1968 wayne. So long as the Register Predictor receives a uvm_reg_bus_op object for eachThe TLM FIFO provides storage for the transactions between two independently running processes. The usage of Factory involves three steps. answered Jun 19, 2014 at 23:32. This method calls uvm_event_base::wait_ptrigger followed by. For objects, pack 4 bits prior to packing the object itself. The utils macros define the infrastructure needed to enable the object/component for correct factory operation. It attempts to mirror the design registers by creating a model in the verification testbench. Inline constraints (i. The UVM class library provides the basic building blocks for creating verification data and components. 1-289-695-1969 shihua. UVMObject (name: str) [source] ¶ Bases: sv_obj. The UVM Test typically performs three main functions: Instantiates the top-level environment, configures the environment (via configuration objects, factory overrides or the configuration database), and applies stimulus by. UVM REPORTING The uvm_report_object provides an interface to the UVM reporting facility. 02. by The Art of Verification. A policy class to allow pairs of transactions to be handled as a single uvm_object type. H. uvm_resource_pool rp = uvm_resource_pool::get(); uvm_resource#(T) _type = new(); uvm_queue#(uvm_resource_base) q; q =. The uvm_heartbeat class is derived from uvm_object and it is associated with a specific objection object. Agent includes a UVM sequencer to manage stimulus flow, a UVM driver to apply stimulus to the DUT interface, and a UVM monitor to monitor the DUT interface. このページの最後に載せておきます。. OOP enables writing reusable code. Methods: Description: set(uvm_component cntxt, string inst_name, string field_name, T value); Create a new or update an existing field_name configuration setting based on cntxt and inst_name. Pack A class called Packet is defined with some variables to store address and data, and is registered with `uvm_field_int macros to enable automation. You're trying to assign a handle of base class type to a handle of derived class type, which isn't allowed in SV. do_pack. A memory is a collection of contiguous locations. When the factory is called upon to create an object. class my_driver. uvm_component provide a set of convenience functions that call the uvm_factory member functions with a simplified interface. When set, metadata should be encoded as follows: For strings, pack an additional null byte after the string is packed. The uvm_comparer adds up policy for the comparison and counts the number of miscompares if any. Intro. Objects using set() and get() must use exactly the same name, otherwise the receiving party (get()) will fail to find the object from uvm_config_db. A policy class to allow pairs of transactions to be handled as a single uvm_object type. A UVM sequence is just a SystemVerilog object that is constructed by calling new. The code inside that class does something similar to what class A did above, except that it builds a global list of all string names and their associated types that can be used by the factory. A parent creates a child, and the uvm_component represents a hierarchal family tree in a database. The difference between a UVM Object and a UVM Component is that UVM components are non-transient, meaning they have a static nature. The important thing to remember is that each entry needs a unique field name or label (if the global scope is being used), or the path needs toThese macros are used to start sequences and sequence items on default sequencer, m_sequencer. The uvm_object class is the base class for all UVM data and hierarchical classes. 1 library. Refer to “Macros” in the UVM 1. Classes derived from uvm_object must implement the pure virtual methods such as create. The monitor captures values on the DUT's input and output pin. The uvm_resource#(type T) is a parameterized class that provides additional functions like read() and write() for resource operation. Yes, each component’s run_phase is executed in a separate process. That means the default value is going to be used in new(). events. A cleaner implementation would have been for uvm_component_registry to be its own class. Inside uvm_component_registry class there is a get method, which. pyuvm implements the most often-used parts of the UVM while taking advantage of the fact that Python does not have strict typing and does not require parameterized classes. Factory is a singleton object and there is only one instance of the factory in a UVM environment. 2 Class Reference for information on the. Include the class inside the testbench and instantiate an object. In our case, two uvm_queues are created; one for the "jb_if1" and the other for the "jb_if2". trace_mode(): Set or get the trace mode for the objection object. For overriding uvm_object or sequences, type overriding is recommended to use since instance overriding requires a hierarchical path. method_call() is really method_call(. You need to create a uvm_object temp variable, then do an explicit dynamic cast, e. Step #1: Create a base callback class. The configuration object also allows for a higher-level view of the DUTs functions, providing test writers with an abstracted constraint layer not tied to the underlying registers. That method looks through an array of type overrides to see if you ever called set_type_override () for this class, then calls new () for the base or override class. It works with uvm_object and interface. That's it. Using macros like `uvm_do , `uvm_create, `uvm_send etc; Using existing methods from the base class a. The intention behind a virtual function is to support polymorphism. uvm_config_db is a parameterized class that is parameterized with the data type of object that is being set or get. Some Standard Data Methods of the uvm_object Class By now you might think that these field macros are convenient but not efficient. this(obj)). get_trigger_data. Posted November 30, 2015. Stimulus는 아직 작성하지 않고, testbench 골격만을 작성해 봅니다. This locking mechanism is implemented using lock and grab methods. Jun 20, 2014 at 15:13. 1. By applying stimulus to the register model, the actual design registers will exhibit the changes applied by the stimulus. My company (Doulos) recommends you. The documentation only instructs on how to unzip the tar. A cleaner way would be to use the sequence library provided by UVM as uvm_sequence_library. Blocks. Implementations of uvm_object::do_pack and uvm_object::do_unpack should regard this bit when performing their respective operation. 02. The scope of the randomize() object is the this argument inside. I need to pass parameters to each element of this array. The handle to the uvm_resource object is stored in two kinds of uvm_queues. Posted November 30, 2015. Using do_record. Class Hierarchy Class Definition See full list on chipverify. It serves an important role to define a set of methods such as create, copy, print, clone, compare, record, etc. uvm_resource_db; uvm_config_db; Passing interface handle and two agent example; UVM testbench Top; UVM Test; UVM Environment; UVM Sequence Items; UVM Driver;The uvm_driver is parameterized to accept a class object of the type my_data and the driver is expected to unpack this class object and drive the signals appropriately to the DUT via the interface. Similarly uvm_object::compare() calls the __m_uvm_field_automation() with UVM_COMPARE. Without it, registration would require an instance of the object itself. uvm_object - Data structures for testbench configuration; uvm_transaction - Stimulus generation & analysis; The values of the arguments of new method are used to create an entry in a linked list which the UVM uses to locate uvm_components in a pseudo hierarchy, this list is used in the messaging and configuration mechanisms. First, let's. randomize with {…} or `uvm_do_with) permit specifying additional constraints when randomizing an object. Pass config objects inside your testbench with OOP-style set_config() methods, instead of the confusing uvm_config_db. the reason for this is that for IUS the m_inst_id is being set to the. This flexibility allows comprehensive testing of different configurations using a single, reusable testbench, significantly reducing development time and effort. Follow. Inside a uvm_env class, I try to create an array of another uvm_env class. Improve this answer. 07 Flow Control 01. Not sure how that is going to help. Interfaces can contain tasks, functions, parameters, variables, functional coverage, and assertions. // Step 1: Declare a new class that derives from "uvm_test" class base_test extends uvm_test; // Step 2: Register this class with UVM Factory `uvm. 2. 2. This is not a complete design since our purpose is simply to show how registers in this design can be read/written using a UVM register model. In other words, uvm_objects are transient, such as transactions that are created when needed and disappear when not used anymore. Uvm_env. virtual function uvm_object. The do_pack() method is called by the pack(), pack_bytes(), and pack_ints() methods. Interfaces can contain tasks, functions, parameters, variables, functional coverage, and assertions. This is applicable for uvm objects and components. The clone () method was declared in uvm_object and returns a handle of type. UVM also introduces a bunch of automation mechanisms for implementing print , copy , and compare objects and. __init__() if you override the __init__() method in a uvm_component. Object and component types are registered with the factory using lightweight proxies to the actual objects and components being created. 02. All components and object classes in a UVM environment are derived from uvm_object base class. 0 ‐ Their Use in Verification and UVM The prototype of the virtual function in Figure 1 is the header code: virtual function bit do_compare (uvm_object rhs, uvm_comparer comparer); This virtual method prototype includes five required elements: (1) the return type is bit, (2) theIn Introduction, we saw that most of the verification components are inherited from uvm_report_object and hence they already have functions and methods to display messages. Description. A class called Packet is defined with. In order to understand the different role that the Accellera Portable Test and Stimulus (PSS) standard plays versus UVM, let's consider this brief statement about what PSS is intended to accomplish, taken from the 1. The name of an uvm_event is unique, you can use uvm_event_pool to get the instance of the uvm_event with the same name. endclass This means that our long list of assignments that the copy expands to would also contain: copy. Bases: object. Then from your component, do. We would like to show you a description here but the site won’t allow us. The service class provides a static <::get> which returns an instance adhering to uvm_coreservice_t. Phases : UVM defines a set of simulation phases that enable users to control the order in which testbench components are created, initialized, and executed. 01 Simulation 환경 01장 SystemVerilog for Testbench 01. This class will also need to be able to get information from the config_db using hierarchical paths, and plain old uvm_objects don't have hierarchy. “virtual” keyword is common in all of them. Since the uvm_sequence_item class is extended from the uvm_object class, it inherits the print method which is used to display the class variables. 39. The driver receives the item and drives it to the DUT through a virtual interface. 02 SystemVerilog 기초 1 01. The UVM methodology enables engineers to quickly develop powerful,. 4) uvm_object required to define the uvm_object::creat() method. 2 Class Reference for information on the uvm_object_utils_begin, uvm_object_utils_end, uvm_field_*, and their associated macros. 작성해 보고자 하는 Testbench 형태는. Steps to create a UVM environment. In Manufacturing, Casting is a process in which liquid metal is converted into the desired object. You can use wildcards in the. Share. uvm_env is extended from uvm_component and does not contain any extra functionality. The utility macros help to register each object with the factory. It is extended from its parent class uvm_resource_dbMarch 24, 2021. For transactions, the typical constructor is shown in Example 2. An appropriate `uvm_field_* macro is required to use based on the data type of class properties. uvm_config_db#(TYPE)::set(this,"*. Understand the UVM hierarchies and various components needed to build a comprehensive UVM Testbench; Design and implement various testbench components, such as driver, monitor, sequencer, agent, environment, scoreboard, coverage, and environment. The packer determines how the packing. Let's take an example of three sequences, all derived from the same base_sequence class, as we. 1. The uvm_object_registry serves as a lightweight proxy for a uvm_object of type T and type name Tname, a string. All counts are cleared and the any processes waiting on a call to wait_for(UVM_ALL_DROPPED, uvm_top) are released. The first kind of queues store the handles to the uvm_resource objects that have the common field_name. is just the same as the previous two, you need to use them when your uvm_object or uvm_component has parameters. def compare_field (self, name, lhs, rhs, size, radix = UVM_NORADIX): """ Function: compare_field Compares two integral values. In order to create a user-defined sequence : Derive from uvm_sequence base class with a specified data object type. Uvm factory is one of the most notable term when using uvm methodology. You're trying to assign a handle of base class type to a handle of derived class type, which isn't allowed in SV. How to use UVM Factory. The tutorial explains the UVM concepts, structure, coding style, and best practices with examples. The user can simply apply a different. It is a standardized methodology for verifying digital designs and systems-on-chip (SoCs) in the semiconductor industry. A user-defined printer has been developed by us. This object must be factory-enabled. 05 Data Arrays 01. Then you can do: typedef uvm_object_registry# (abc_test_seq,`STR (`SEQ_NAME (abc))) type_id;. A uvm_queue is created for every unique field_name. 04 Packed and Unpacked arrays 01. It is an abstract class with no data members or functions. Your sequence would have, instead of an array of pixels, an array of ints, and then you could transform from/to in the driver and monitor. SystemVerilog Parameterized Classes. Constraints may be added via inheritance in a derived class. The primary role of uvm_object class is to define a set of common utility functions like print, copy, compare and record which can be availed by any other class in a UVM testbench to save effort. That is the macro call is delegated to a uvm_report_error() function call. 09. This article explains how to use a verbosity threshold to filter messages. `uvm_field_utils_begin. gz. UVM Testbench 작성 00장 둘러보기 00. UVM Field Macros. 2 User’s Guide. `uvm_field_utils_end. UVM provides a transaction class that can be extended to create transaction objects that carry information between the DUT and the testbench. UVM components support logging with the following steps. 02. It attempts to mirror the design registers by creating a model in the verification testbench. An appropriate `uvm_field_* macro is required to use based on the data type of class properties. Share. We need to plan for it by structuring our code in certain ways. sv" into the same package you probably need to import the package where monitor. Static components & Dynamic components. Testbench diagram. Each of UVM’s policy classes performs a specific task for uvm_object-based objects: printing, comparing, recording, packing, and unpacking. For Design specification and Verification plan, refer to Memory Model. Does an abstract class (virtual class. In our case, two uvm_queues are created; one for the "jb_if1" and the other for the "jb_if2". It is an abstract class with no data members or functions. After the utility macro are the field automation macros in the form ‘uvm_field_*(data member, flag). Why the factory is important, though, and how it helps us achieve that goal may be. Both UVM Factories allow you to create objects, either the base type or a derived, without changing the call to create(). This keeps your code base stable,. If we were to have a variable of type uvm_object (where get_type_name is first defined), we could store. March 24, 2021. Only classes derived from uvm_component have knowledge of their parentage. uvm_object¶ class uvm. com Each component goes through a pre-defined set of phases, and it cannot proceed to the next phase until all components finish their execution in the current phase. Subtypes of uvm_printer implement different print formats, or policies. uvm_comparer is the standalone class used to set a policy for doing comparisons and determines how miscompares are counted. base. An uvm_component inherits from. wait_trigger_data. That means the default value is going to be used in new(). Every class item derived from uvm_object will have a printer instance within it. Alternatively, if the change is intended to be global, there is a default printer that automatically created at root called uvm_default_printer . Accellera believes standards are an important ingredient to foster innovation and continues to encourage industry innovation based on its standards. One thing that always confuses me: is whether add uvm_component parent in the class constructor of UVM objects or not. 在使用UVM 寄存器的时候，本质是将high_level的uvm_reg_transaction (也叫uvm_reg_item)转换成物理的transaction (物理dirver所使用的transaction,用户定义的BUS_transaction),转换过程是. A environment class can also be. Its primary role is to define a set of methods for such common operations as create, copy, compare, print, and record . But that's another debate. set_type_override_by_name ("base_sequence",`STR (`SEQ_NAME (abc))); In. Write this register if the DUT register is out-of-date with the desired/mirrored value in the abstraction class, as determined by the uvm_reg::needs_update () method. trigger. TimConclusion. Enjoy your verification journey!SystemVerilog functions have the same characteristics as the ones in Verilog. Type override in UVM factory. uvm_object is the main class in which common functions to print, copy, and compare two objects of the same class are defined. But that is not the case and like the commonly. This makes them more flexible, and able to work on a range of data types instead of just a single one. 2 User’s Guide. 06 Array Operators and Methods. UVM Debugging features. Strictly speaking, you can define the do_print without using the uvm_printer, but if you do so, you are not able to. Thus, it can save the simulation time and terminate it at an early state. Print method; Copy and clone methods; Compare method; Pack / Unpack methods; Resource database in UVM. 2 Class Reference represents the foundation used to create the UVM 1. uvm_transaction and uvm_component are also derived from uvm_object. Improve this answer. uvm event callbacks are an alternative to using processes that wait on events. static function bit get(uvm_component cntxt, string inst_name, string field_name, inout T value, input uvm_object CALLING_CONTEXT = null, input string FILE = "", input int LINE = 0); With these additions every time we do a set, we remember where this set came from. S. Implement the callback method. Using UVM in SystemC is a tutorial paper that presents the benefits and challenges of applying the Universal Verification Methodology (UVM) to SystemC-based verification environments. In uvm_object, we discussed print, clone, copy, compare methods, etc. The UVM TLM library defines several abstract, transaction-level interfaces and the ports and. Here is my thought/search process: I've found that uvm_factory class has a register method which registers a proxy object of a given type. env. UVM REPORTING The uvm_report_object provides an interface to the UVM reporting facility. The first kind of queues store the handles to the uvm_resource objects that have the common field_name. 613. Factory is a singleton object and there is only one instance of the factory in a UVM environment. With Easier UVM, configuration parameters should be accesed by calling uvm_config_db # (T)::get. The uvm_component_registry class extends uvm_object_wrapper and implements its create_component() function, but it also has many other functions related to registering itself with the factory and handling type overrides. uvm_report_object. dave_59. Abstract- SystemVerilog provides several mechanisms for layering constraints in an object. Jun 20, 2014 at 15:54. System Verilog has virtual methods, virtual interfaces, and virtual classes. : bit get(uvm_component cntxt, string inst_name, string field_name, inout T. and a whole lot more!using EDA Playground VHDL Verilog/SystemVerilog UVM EasierUVM SVAUnit SVUnit VUnit TL-Verilog e + Verilog Python + Verilog Python Only C++/SystemC. Improve this answer. event_object_h =. virtual class uvm_component extends uvm_report_object; uvm_component class definition provides many functions and tasks that are used to find, build, connect, and configure. 2 uvm_object constructor. The `name` input is used for purposes of storing and printing a miscompare. System Verilog has virtual methods, virtual interfaces, and virtual classes. For example a test might be pseudo-coded as:Hi, experts, I met one problem when i use type_id::create() to create one instance of a component object. Q&A for work. e. build_phase (phase) must be called in the. 2에서는 반드시 constructor를 기술하여야 한다. The UVMObject class is the base class for all UVM data and hierarchical classes. The first step is to use macros to register all the class types with the factory. The UVM sequencer provides the facility to have exclusive access for the sequence to a driver via a sequencer using a locking mechanism. As you say, the UVM field automation macros generate a number of class utility methods such as copy, print and clone that include the registered fields. That means the other parameter Tname of. Objects of this type will be used by sequences. 1 Answer. This is a message generated by vcs: Error- [ICTTFC] Incompatible complex type usage Incompatible. uvm_object like uvm_transaction is not connected to any particular DUT interface and its fields can take any random value based on randomization constraints. UVM pre-defines six verbosity levels; UVM_NONE to UVM_DEBUG. Objections provide a facility for coordinating status information between two or more participating. uvm_object. uvm_object is the one of the base classes from where almost all UVM classes are derived. I did not register any class with the same name, unless the parent one which, I suppose, does not present any problem. As I understood for all items inherited from uvm_component, they all need uvm_component parent as part of constructor input argument. You are mixing up the terms parent and child with the principals of class inheritance. So, a data class derived from uvm_sequence_item or uvm_component will have access to the print() function as well. In the UVM, there are mechanisms to automate the retrieval of data from the configuration database. The. So, a data class derived from uvm_sequence_item or uvm_component will have access to the print() function as well. Hence, it is required to have proper synchronization to avoid objects/components being called before they are created, The UVM phasing mechanism serves the purpose of synchronization. I can't use a generate loop inside the class and I couldn't find out a way to use a for loop to pass the individual parameters. UVM tutorial for beginners Introduction Introduction to UVM UVM TestBench TestBecnh Hierarchy and BlockDiagram UVM Sequence item Utility & Field Macros Methods with example Create Print Copy Clone Compare Pack UnPack UVM Sequence Sequence Methods Sequence Macros Sequence Example codes UVM Sequence control UVM. data = 2; t1. The uvm_event class is directly derived from the uvm_object class. However, are they supported by UVM?When working with UVM, the phrase "you gotta use the factory!" gets drilled into our heads constantly. Such a. Abstract- SystemVerilog provides several mechanisms for layering constraints in an object. As the name suggests, it keeps a track of the sequences that are registered with it, and calls them a number of times in a random fashion. It performs a deep copy. new (name, parent); endfunction. The create method internally makes a call to the factory to look up the requested type and then. The set_type_override() is another static function of the uvm_object_registry. I've used uvm_queue because there isn't any trivial container object in UVM. If no argument is specified (or an argument. A block represents a design hierarchy. Field definition remains the same as print_field method. Similarly uvm_object::compare() calls the __m_uvm_field_automation() with UVM_COMPARE. // For example, "set_type_override_by_type" is actually a function defined in the class uvm_factory // A. For example, if the knobs says we're in a certain mode, and the sequence shall be constrained according to the mode, then the knobs must be available at sequence pre/post/randomize(), it is too late to read them from a. myagent. As an additional aside, it's also important to acknowledge that while uvm_object does provide a pack/do_pack/do_unpack interface, there's zero restrictions on where a packer can actually be used. OOP enables writing reusable code. First up, let’s briefly cover the semaphore and uvm_pool. A block has one or more address maps, each corresponding to a physical. Yes, the UVM create() method calls new() constructor on the object without any arguments (string name is not passed in there). User classes derived directly from uvm_void inherit none of the UVM functionality, but. This is useful when you want to affect the with in a particular uvm_object can can be made scalable by overriding the do_print() method. Both the main sequence and the other sequence get an uvm_event with. Register the callback class. You can either have a drive_item task in the driver, or you can call a. It allows for generic containers of objects to be created, similar to a void pointer in the C programming language. The paper explains how UVM can be integrated with SystemC using the UVM-ML Open Architecture, a framework that enables interoperability between different. 1 Inheritance and Constraint Layering ¶ In our previous two posts in this series on Python as a verification language, we examined Python coroutines and using coroutines to create cocotb bus functional models. “virtual” keyword is common in all of them. uvm_object-based class declarations may contain one of the above forms of utility macros. to drive the designated signals into DUT. 4. Because this will be created during the run_phase it can't extend uvm_component, and it wouldn't make sense for this class to have phases. The reason being packet and packetD are type compatible, since packetD is an extension of packet. e. The word “factory” in UVM refers to the substitution of any object or component in the verification environment without modifying any part of code in any testbench. They allow access to the functions copy, compare, pack, unpack, record. UVM contains primarily 2 types of components i. Classes deriving from UVMObject must implement methods such as create and get_type_name. The factory (or to be precise, uvm_component_registry) will call new on behalf of you. Users can configure what actions are taken and what file(s) are output for individual messages from a particular component or for all. Using Callback. After all, you just set the value of data and id with the name “t1”.