We designed LSI's in "sea of gates" using schematics, often with a lot of 'em on one sheet. I can remember perfectly readable schematics consisting of 75 sheets, size "E" and not using the military standard symbol sizes, but using the smallest symbols on the template, so there were often 500-600 components on a sheet.

Anyone worth his salt could read and comprehend those sheets with a bit of time, and, I guarantee you, if it was drawn by someone with any sense at all, it was much easier to read and understand than the equivalent HDL.

HDL's are popular with coders because they don't have to get their hands dirty, and don't have to commit themselves to anything they can't edit away. They are pretty good for expresing some functions, e.g. a binary to 7-segment encoder, which takes a 'B' size schematic if you draw out all the gates, yet it fits on half a page of VHDL. There are MANY other such functions, but there are also some that are very easily and clearly expressed in schematic diagrams.

BTW, how do you specify, say, a 48-bit value in decimal notation in VHDL?

RE