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Verilog is weird
danluu.com
Highlights
How is it possible that a reasonable description of something in Verilog turns into something completely wrong in hardware? You can think of hardware as some state, with pure functions connecting the state elements. This makes it natural to think about modeling hardware in a functional programming language. Another natural way to think about it would be with OO. Classes describe how the hardware works. Instances of the class are actual hardware that will get put onto the chip. Yet another natural way to describe things would be declaratively, where you write down constraints the hardware must obey, and the synthesis tool outputs something that meets those constraints. Verilog does none of these things. To write Verilog that will produce correct hardware, you have to first picture the hardware you want to produce. Then, you have to figure out how to describe that in this weird C-like simulation language. That will then get synthesized into something like what you were imaging in the first step
Verilog is so inexpressive that many companies use an ad hoc tool to embed a scripting language in Verilog or generate Verilog from a scripting language.
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