Similar Posts
How to use a procedure in VHDL
A procedure is a type of subprogram in VHDL which can help us avoid repeating code. Sometimes the need arises to perform identical operations several places throughout the design. While creating a module might be overkill for minor operations, a procedure is often what you want. Procedures can be declared within any declarative region. The…
How to use Port Map instantiation in VHDL
A module is a self-contained unit of VHDL code. Modules communicate with the outside world through the entity. Port map is the part of the module instantiation where you declare which local signals the module’s inputs and outputs shall be connected to. In previous tutorials in this series we have been writing all our code…
How to use a Case-When statement in VHDL
The Case-When statement will cause the program to take one out of multiple different paths, depending on the value of a signal, variable, or expression. It’s a more elegant alternative to an If-Then-Elsif-Else statement with multiple Elsif’s. Other programming languages have similar constructs, using keywords such as a switch, case, or select. Among other things,…
How to stop simulation in a VHDL testbench
How do you stop the VHDL simulator when the simulation is complete? There are several ways to do that. In this article, we will examine the most common ways to end a successful testbench run. The VHDL code presented here is universal, and it should work in any capable VHDL simulator. For the methods involving…
How to check if a vector is all zeros or ones
I know that I have googled this at least a hundred times throughout my career as an FPGA engineer; how to check if all bits in a std_logic_vector signal are ‘0’ or ‘1’. Of course, you know a few ways to do it already, but you want to find the most elegant code that will…
How to use constants and Generic Map in VHDL
Creating modules is a great way to reuse code, but often you need the same module with smaller variations throughout your design. This is what generics and the generic map are for. It allows you to make certain parts of the module configurable at compile-time. Constants are used when we want to avoid typing the…
Though those two codes are logically equivalent, the right one infers a transparent latch, it shouldn’t be used for synthesis.
I don’t think it does, but I’m not 100% sure what the synthesis tools do all the time.
This will infer a latch:
process(InSig) is begin if InSig = '0' then OutSig <= '1'; end if; end process;This shouldn’t create any latches:
process(InSig) is begin OutSig <= '0'; if InSig = '0' then OutSig <= '1'; end if; end process;A link to the question:
https://vhdlwhiz.com/wp-content/uploads/2017/09/quiz_part-2-q6.png
Hi sir, You designed this course very well and advanced. I am happy to recommend this course to my friends.
I’m glad you enjoyed it! And thanks for taking the time to leave a nice comment.