How do I simulate a VHDL code in ModelSim?

How do I simulate a VHDL code in ModelSim?

Step 4: Start Simulation

1. Go to Simulate, click Start Simulation.
2. At the Design tab, search for work, then expand the work and select your testbench file.
3. At the Libraries tab, click Add.
4. Select library lpm, then click OK.
5. Repeat step 3 for more libraries.
6. Click OK.

What is vopt in ModelSim?

defines a mapping between a logical library name and a directory. vopt. produces an optimized version of your design. vsim. loads a new design into the simulator.

How to calculate the time in VHDL application?

The to_real function returns real value of time parameter scaled to current resolution unit. If simulation resolution is 10 picoseconds, to_real (1 ns) returns 100.0 . The to_time function will return time value of its real argument, treating the argument as the number of simulation resolution units.

How to get simulation time instant in ModelSim?

I know when using report and severity Modelsim displays the simulation time instant as part of its message to the console. Is there anyway to “get” this time instant as a string variable so I can print my own message with this “time” string? The simulation time is available through the now function, which will a return the value as time type.

How to calculate granularity of time in VHDL?

Please note that range of values of the type is described using 32-bit signed integer, not real type. It means that the granularity of time in VHDL cannot be finer than 1 fs: decimal fractions of time can only happen if the secondary time units are used.

Why are 64-bit signed integers used in VHDL?

It means that 64-bit signed integers can cover time values within 1 femtosecond to over 2.56 hour range, which seems reasonable for majority of applications. That’s why VHDL simulators typically use 64-bit time representation.