Tutorial by Examples

Digital hardware is built from two types of hardware primitives: Combinatorial gates (inverters, and, or, xor, 1-bit full adders, 1-bit multiplexers...) These logic gates perform a simple boolean computation on their inputs and produce an output. Each time one of their inputs changes, they st...

This example is the second of a series of 3. If you didn't yet, please read the Block diagram example first. With a block diagram that complies with the 10 rules (see the Block diagram example), the VHDL coding becomes straightforward: the large surrounding rectangle becomes the VHDL entity,...

This example is directly derived from John Cooley’s design contest at SNUG’95 (Synopsys Users Group meeting). The contest was intended to oppose VHDL and Verilog designers on the same design problem. What John had in mind was probably to determine what language was the most efficient. The result...