I’m from Norway, but I live in Bangkok, Thailand. Before I started VHDLwhiz, I worked as an FPGA engineer in the defense industry. I earned my master’s degree in informatics at the University of Oslo.
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Basic VHDL quiz
Have fun and learn from this VHDL and FPGA design quiz with 28 questions for beginners and intermediate learners in random order.
All questions include an explanation for the correct answer that will be shown after you make your selection.
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How to create a timer in VHDL
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RC servo controller using PWM from an FPGA pin
Radio-controlled (RC) model servos are tiny actuators typically used in hobbyist model planes, cars, and boats. They allow the operator to control the vehicle via a radio link remotely. Because RC models have been around for a long time, the de-facto standard interface is pulse-width modulation (PWM), rather than a digital scheme. Fortunately, it’s easy…
First of all, thank you so very much!
These are by far the most comprehensible tutorials I have come across like ever!
Brilliant work.
So here my two cents out of gratitude:
Basic VHDL Quiz – part 4
Which statement is not true?
Answer 3 : The return statement cannot be omitted.
-> Correct
So the return statement CAN be omitted???
“Unlike in most other programming languages, the return keyword is mandatory in functions in VHDL.”
Confused by double negation. Me or you 😉
Good catch! I’ve changed the answer now. I was trying to make you think, but in the process I confused myself too 🙂
“The return-keyword cannot be used in a procedure”. I believe that this is incorrect, e.g.
https://web.archive.org/web/20200629023040/http://vhdl.renerta.com:80/source/vhd00060.htm
It is true, of course, that you cannot return a value with it, that’s the only (?) difference between procedures and functions. But, as in other languages, you can use “return” as control flow statement to “force an exit”.
You are right! I missed the possibility of using return statements in procedures without returning a value. According to the Renata link you posted, functions must return a value, while procedures can have return statements, but then without a return value.
I am changing this question.