Module instance

A module instantiation statement can be written within a module declaration. A synthesis system treats such a module instance as a black box and does not take further action, that is, the module instance appears in the synthesized netlist as if it were a primitive component. Here is an example of a full-adder module that contains one module instantiation statement. Notice that in the synthesized netlist, shown in Figure 2-67, the module MyXor appears just as it is described in the top level module FullAdderMix. 

Figure 2-67 A module instance mixed with behavior.

The UART top-level model glues all these blocks together using module instantiations. The microprocessor entity, MP, is described in the structural style, that is, using module instances. The remaining three are described using the behavioral style. In this chapter, only the behavioral blocks are described. 

In this chapter, we assume that the synthesis process produces a synthesized netlist in Verilog HDL as shown in Figure 5-1. A Verilog HDL netlist is a collection of module instances interconnected by nets. 

If vectors from a stimulus file were applied, say every 1 ns, and all the module instances in the netlist represent behavioral models with no delay, the results between the design model and the netlist will be skewed because of the difference in delays. The correct approach in such a case is ... 

It could happen that a synthesized netlist has a module instance with an unconnected input port. Such a case is shown in the following example. 

Notice that in the synthesized netlist, the first input of the AND2 module instance Sl l is open. During the simulation of module AOI22 NetList, the open input takes the value z whereas the unassigned value of C in module AOI22u takes on a default value of x. The fact that different values are used for C during the design model simulation and the synthesized... 

The correlation of modularity and commonality is embodied in the class-member relationships. A product structure is defined in terms of its modularity where module types are specified. Product variants derived from this product structure share the same module types and take on different instances of every module type. In other words, a class of products (product family) is described by modularity and product variants differentiate according to the commonality among module instances. 

The internal structure of each module is represented by defining the contained module instances. Again,the... 

Dmm diameters are typically 762, 914, or 1219 mm, all of which have been used in the various basic appHcations. In some instances, standardization of diameter is specified because of maintenance considerations. Because these separators are constmcted more mggedly and requHe repulping stages, capital costs are higher than heavy-media separators. Costs in 1995 were approximately 10,000/m of width for single-dmm modules and multiples of the single-dmm module. 

Complex manufacturing systems, such as an unbleached Kraft pulp plant (Fig. 9), are almost always characterized by some type of internal structure, composed of a number of interconnected subsystems with their own data collection and decisionmaking responsibilities. This raises a number of additional issues, not addressed in previous sections. For instance, if the learning methodology described in Section VI is applied to the digester module of a pulp plant (Fig. 9), it is possible for the final selected solution, to include ranges of desired values of sulfidity... 

Evidence suggests that co-transmitters in a terminal have their own autoreceptors and, in some cases, activation of their own presynaptic receptor can influence the release of the co-stored, classical transmitter. For instance, activation of P2Y-autoreceptors by ATP is thought to affect the release of noradrenaline from sympathetic neurons. However, in other cases, feedback modulation of release of classical and their associated co-transmitters seems to have separate control mechanisms. This would suggest that either the two types of transmitter are concentrated in different nerve terminals or that mechanisms for regulating release target different vesicles located in different zones of the terminal (Burnstock 1990). 

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