circuit

What are the easiest steps to make a small circuit with an LED flash from a C/C++ program? I would prefer the least number of dependencies and packages needed. What port would I connect something into? Which compiler would I use? How do I send data to that port? Do I need to have a micro-processor? If not I don't want to use one for this simple project. EDIT: Interested in any OS specific solutions. mwilliams Here's a tutorial on doing it with a parallel port . Though I would recommend an Arduino which can be purchased very cheaply and would only involve the following code: /* Blinking LED * -

int i=-3, j=2, k=0, m; m = ++i || ++j && ++k; printf("%d, %d, %d, %d\n", i, j, k, m); Since ++ has more precedence than || and && in C, they are evaluated first and therefore the expression becomes m = -2 || 3 && 1 . Now you can apply short circuiting but that produces incorrect answer. Why is that? Precedence ≠ order of evaluation. The short-circuiting behavior of || and && means that their left-hand sides are evaluated first, and If the LHS of || evaluates to true (nonzero), the RHS is not evaluated (because the expression will be true no matter what the RHS is) If the LHS of && evaluates to

This question already has an answer here: Using wire or reg with input or output in Verilog 5 answers I'm confused about reg and wire when I was doing my homework. I could not understand differences between reg and wire exactly. Can you explain shortly? Also, I wonder that what will happen when I use output q instead of output reg q ? In simulation , a Verilog wire behaves like a piece of metal, a track, a wire, whilst a Verilog reg is a variable, it is storage*. The difference between them in simulation can be illustrated by showing what happens if I assign to them from more than one place.

How are bit shifts implemented at the hardware level when the number to shift by is unknown? I can't imagine that there would be a separate circuit for each number you can shift by (that would 64 shift circuits on a 64-bit machine), nor can I imagine that it would be a loop of shifts by one (that would take up to 64 shift cycles on a 64-bit machine). Is it some sort of compromise between the two or is there some clever trick? The circuit is called a " barrel shifter " - it's a load of multiplexers basically. It has a layer per address-bit-of-shift-required, so an 8-bit barrel shifter needs