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Both "books" are kind of regrettable, but SR flip-flops and 7400-type logic gates are essential background knowledge for writing HDL. You'll have a hard time de
by jff 12y ago
Both "books" are kind of regrettable, but SR flip-flops and 7400-type logic gates are essential background knowledge for writing HDL. You'll have a hard time describing hardware if you don't know what kind of hardware you're trying to describe... Verilog looks vaguely C-ish, but in the end you're describing how to connect up a bunch of flip-flops and logic gates.
- adwn 12y agoIn modern digital hardware design, you only use D flip-flops (with some very rare exceptions), so teaching SR, JK etc. is not only unnecessary, but also confusing to beginners. Showing how to build them from gates is even worse, because it's typically wrong and results in a level-triggered latch (which you don't use in modern digital hardware design). You don't build more complex functions like adders or multiplexers from individual gates anymore, so don't put beginners into this outdated mindset. Sure, explain how to build a half-adder from ANDs and XORs, but make it clear that they shouldn't do this for anything except experimentation; you don't need any specific parts like the 7400s for this. Instead, teach them proper design techniques with HDLs (as horrible as VHDL and Verilog are, they are better than schematic designs).
- jff 12y agoWell, when I did VLSI, I built adders from individual gates... but I only took one course in VLSI, so maybe I'm wrong.