Why is initial block not synthesizable?

An initial block is not synthesizable and hence cannot be converted into a hardware schematic with digital elements. Hence initial blocks do not serve much purpose than to be used in simulations. These blocks are primarily used to initialize variables and drive design ports with specific values.

Is initial block synthesizable in FPGA?

Initial blocks can be used in either synthesizable or non-synthesizable blocks. Initial blocks only operate once. A synthesizable initial block is used to set the power-on value of registers, RAM, and ROM within FPGAs.

What are synthesizable and non-synthesizable constructs?

Synthesizable Verilog is that subset of the language that are accepted by the synthesis tools. The non-synthesizable constructs are used only for simulation and the synthesis tool cannot handle them.

What is synthesizable and non-synthesizable code?

When you write you Verilog or VHDL code, you are writing code that will be translated into gates, registers, RAMs, etc. The program that performs this task is known as a Synthesis Tool. When you write code like this, it is called non-synthesizable code.

Why is initial not synthesizable in Verilog?

Initial block is not synthesizable, this is because initial block runs only once in the simulation. In real hardware, there is no such concept as running only once. Hence, they are not synthesizable in ASICs which is a real hardware.

What is the difference between an initial and final block of the Systemverilog?

What is the difference between initial block and final block? Initial block is getting executed at start of simulation while Final block is getting executed at end of simulation. You can schedule an event or have delay in initial block But you can’t schedule an event or have delay in final block.

What is synthesizable and non-synthesizable in VHDL?

synthesizable are those which will generate some hardware when implemented. and non-synthesizable are those which dont generate any kind of hardware, they are just the instructions for the compiler/assembler.

Why delays are not synthesizable in Verilog?

But delays have to be multiples of the clock of that element. Usually you find things such as “after 10 ns” theses are propagation delays. When doing an ideal simulation on a Verilog simulator, outputs happen exactly when the inputs change. This is not realistic and does not describe the way real hardware work.

What is the difference between initial and always in Verilog?

The difference between the two is that initial processes execute once, whereas always process execute repeatedly forever. As such, an always process must contain timing statements that will occasionally block execution and allow time to advance (time in initial and always process only advances when they are blocked).

What is the difference between the initial block and the final block?

What is difference between initial and always in Verilog?

Initial and always statements describe independent processes, meaning that the statements in one process execute autonomously. The difference between the two is that initial processes execute once, whereas always process execute repeatedly forever. …