Chapter 23. Miscellaneous Topics
In the preceding chapters we introduced most of the facilities provided by VHDL and showed how they may be used to model a variety of hardware systems at various levels of detail. However, there remain a few VHDL facilities that we have not yet discussed. In this chapter, we tie off these loose ends.
Guards and Blocks
In this section we look at a number of closely related topics. First, we discuss another kind of resolved signal called a guarded signal. We see how we can disconnect drivers from such signals. Next, we introduce the idea of blocks in a VHDL design. We show how blocks and guarded signals work together with guards and guard expressions to cause automatic disconnection of drivers. Finally, we discuss ...