- 1 Why do we need program blocks?
- 2 What is a program block?
- 3 Why program block is not used in UVM?
- 4 How does a program block differ from a module?
- 5 Why always block is not allowed in program block?
- 6 What are the advantages of SystemVerilog program block?
- 7 How do you implement always block in program block?
- 8 Can we use always block inside a task?
- 9 What is the difference between initial and final block of SystemVerilog?
- 10 What is polymorphism in SystemVerilog?
- 11 What is the difference between datatype logic and wire?
- 12 What is program block in System verilog?
- 13 Why Forever is used instead of always in program block in SV?
- 14 What is $root in SystemVerilog?
Why do we need program blocks?
The program block serves these basic purposes: -> Separates the testbench from the DUT. -> It provides an entry point to the execution of testbenches. -> It creates a scope that encapsulates program-wide data.
What is a program block?
Block programming is the arrangement of programs on radio or television so that those of a particular genre, theme, or target audience are grouped together.
Why program block is not used in UVM?
Program block is used to differentiate between testbench and DUT. By not using program block in UVM, won’t it kill the important feature of System Verilog?
How does a program block differ from a module?
Program blocks can’t contain UDP, modules, or other instance of program block inside them. Modules don’t have any such restrictions. A program can call a task or function in modules or other programs. But a module can not call a task or function in a program.
Why always block is not allowed in program block?
When the last initial block completes, simulation implicitly ends just as if you had executed $finish. If you had an always block, it would never stop, so you would have to explicitly call $exit to signal that the program block completed. This is the reason why we can not have always block inside program.
What are the advantages of SystemVerilog program block?
SystemVerilog Program Blocks
- To provide an entry point to the execution of testbenches.
- To create a container to hold all other testbench data such as tasks, class objects and functions.
- Avoid race conditions with the design by getting executed during the reactive region of a simulation cycle.
How do you implement always block in program block?
How to implement always block logic in program block? Using forever loop. Convert below always block’s logic using forever loop.
- Program blocks can’t have always block inside them, modules can have.
- Program blocks can’t contain UDP, modules, or other instance of program block inside them.
Can we use always block inside a task?
No. you can not use an always block inside any procedural code, including a task. it creates a process thread by execution of the procedural code within the block.
What is the difference between initial and final block of SystemVerilog?
Final block is a new concept which was introduced in System Verilog. The basic difference between these two are evident from the nomenclature, i.e, Initial block starts getting executed during simulation time t=0 while the Final block gets executed when the simulation is completed.
What is polymorphism in SystemVerilog?
Polymorphism is the ability to have the same code act differently based on the type of an object its working with. SystemVerilog enables polymorphism in two different ways: statically, at compile time, using parameterized classes and dynamically, at run-time, using virtual methods.
What is the difference between datatype logic and wire?
Wire is verilog datatype whereas logic is SystemVerilog data type.
What is program block in System verilog?
module in verilog is used for describing hardware, it can contain, always, intial and assign statments. To have clear sepration between testbench and design, SystemVerilog introduces program, which contains full enviroment for testbench. A Program serves following purpose.
Why Forever is used instead of always in program block in SV?
An always or forever block without a delay element will hang in simulation! In SystemVerilog, an always block cannot be placed inside classes and other SystemVerilog procedural blocks. Instead we can use a forever loop to achieve the same effect.
What is $root in SystemVerilog?
$root is a SystemVerilog construct representing the top of the static elaborated module/interface hierarchy. This hierarchy gets constructed as part of elaboration stage of the compiler and executes before any simulation starts running.