Continuous assignment

We will use the equation of continuity, assigning the subscript 1 to the barrel of the syringe and the subscript 2 to the needle. We are asked to calculate the speed of the medicine through the needle, which is represented by vr Our first step will be to solve the equation of continuity for v2 ... 

Figure 2-1 Combinational circuit from continuous assignment statement.

The continuous assignment statement describes an inverter that has its input connected to Statin and whose output is StatOut. Delays, if any, specified in a continuous assignment statement are usually ignored by a synthesis system. For example, in the continuous assignment ... 

The logical operators get directly mapped onto primitive logic gates in hardware. Here is a model of a full-adder using continuous assignment statements. 

In the first continuous assignment, the result of the operation is five bits and OneUp[4] has the carry bit. If OneUp were declared as ... 

In the above examples on continuous assignments, there is a one-to-one correlation between a continuous assignment statement and its synthesized logic. This is because a continuous assignment implicitly describes the structure. 

Notice the structure of the synthesized circuit is very similar to that of the continuous assignment statements. 

Figure 3-1 Combinational logic from continuous assignments.

Boolean equations represent combinational logic. Boolean equations are best represented using continuous assignment statements. Here is an example of a Gray code to binary code convertor using boolean equations. 

Here is a model of a different simple arithmetic-logic-unit. This logic unit performs four functions add, nand, greater-than and exclusive-or. A continuous assignment statement with a conditional expression is used to model the arithmetic-logic-unit. 

Here is an example of a simple 2-by-4 decoder circuit. This is a combinational circuit modeled purely using continuous assignment statements. Delays specified with the assignment statements, if any, are typically ignored by a synthesis system. 

Here is a model of a 4-by-l multiplexer circuit. In this case, a bit-select in a continuous assignment statement has been used to model the combinational logic. 

Delays specified in a design model may cause a functional mismatch between the model and the synthesized netlist. Here is an example of an adder model that uses a delay in a continuous assignment, and its synthesized netlist. 

Continuous Assignments Supported Delay values and drive strength values ignored. 

The procedure just described can be applied to configurations R(p), found along a parametrized conformational or reaction path. Let p(p) be such a path it can be seen as a continuous assignment from the unit interval I=[0,1] to the configuration space 3Nr (for a backbone made of a sequence of N-1 straight-line segments) ... 

The input to the Workbench is a mixed behavioral and structural description. In Verilog, sequential behavior is described with the always statement, combinational behavior is described with the continuous assignment statement assign), and hierarchical structural is described with module definitions, and module and gate instantiations. For the purposes of the Workbench, the synthesis tools treat the always statement as a single process description of the behavior to be synthesized into a structural data path and controller. For each always statement, a separate controller and data path is generated. 

Workbench. That is, these structural components are not synthesized by the Workbench. However, they define the implicit ports (connections to a continuous assignment and instantiated submodules), and explicit ports (declared ports of the current module) between the behavior described in the always statement and these structural entities. 

The architecture BAD2 takes QBAR out of die process, ensuring that only one flip flop is inferred. However, in doing this, QBAR now becomes an unconditional concurrent signal assignment in which it is continuously assigned the inverted input D. Figure 5.33 illustrates tiiis circuit. The solution is to replace not D with not Q. ... 

Fig. 9 (continued) assignments of correlations from the complex are not available, (b) Residues whose resonances are affected by the IIS interaction are mapped on the proteasome structure, (c) Crystal structure of the llS-proteasome complex, (d) The intensities of resonances during the titration are used to obtain an approximate dissociation constant (irD = 12 10 pM) for the IIS interaction that is consistent with the core particle titration data (see insets). The decrease in intensity of one of the correlations from L81 is shown on the left and the concomitant increase in a bound peak on the right. Errors are quantified from signal-to-noise in spectra. [Ligand] and [Protein] refer to total ligand and protein concentrations. Adapted from [3] with permission... 

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