Re:Ask HN's FPGA users: FPGA tool woes & wants?
by gte910h on Thursday June 03, 2010 @03:45PM
(#1402292)
>Avoid ever referring to it as code
I tend to call verilog or VHDL "VHDL Hardware Specification". Try to make it sound as un codelike as possible
After all VHDL was the way that military contractors came up with to specify their parts to the Govt in case they went belly up.
Re:Ask HN's FPGA users: FPGA tool woes & wants?
by harnhua on Thursday June 03, 2010 @11:06PM
(#1403355)
As I was trained in Verilog and know little about VHDL, to be honest, I'm not quite sure why "code" is inappropriate.
But thinking about your(blasdel's and gte910h's) comments, I'm beginning to see how error-checking can and should be different for FPGA development.
Re:Ask HN's FPGA users: FPGA tool woes & wants?
by blasdel on Friday June 04, 2010 @04:44AM
(#1403842)
Because neither Verilog nor VHDL is code. HDL is a slightly handwavey description of the graph of a machine, not something that runs on a machine.
You have wires, not variables: real physical wires connecting gates and LUTs. Since you're dealing with real-world electrical current, each wire can be in one of four binary states (null, low, high, grey). There's no concept of time beyond the speed of light itself unless you deliberately bind a clock line from the outside to a wire.
The trick would be a synthesis that preserves line-number metadata, and then a linting place-and-route that just creates idealized graphs and lets you see where your design is exploding or clocked funny or whatever.