VHDL Programming

2 Chapter One In 1986, VHDL was proposed as an IEEE standard. It went through a number of revisions and changes until it was ado ...

Introduction to VHDL 3 Bus. The term “bus” usually brings to mind a group of signals or a particular method of communication us ...

4 Chapter One The keyword ENTITYsignifies that this is the start of an entity state- ment. In the descriptions shown throughout ...

Introduction to VHDL 5 The reason for the connection between the architecture and the entity is that an entity can have multiple ...

6 Chapter One statement will not execute because this statement is not sensitive to changes to signal a. This happens because si ...

Introduction to VHDL 7 The two signal assignment statements in architecture behaveform a behavioral model, or architecture, for ...

8 Chapter One The architecture statement area is located after the BEGINkeyword. In this example are a number of component insta ...

Introduction to VHDL 9 WHEN 0 => x <= a; WHEN 1 => x <= b; WHEN 2 => x <= c; WHEN OTHERS => x <= d; END ...

10 Chapter One sequential statements. This means that any statements enclosed by the process are executed one after the other in ...

Introduction to VHDL 11 Architecture Selection So far, three architectures have been described for one entity. Which archi- tect ...

12 Chapter One FOR U7 : orgate USE ENTITY WORK.myor(version1); END FOR; END FOR; END muxcon1; The function of the configuration ...

Introduction to VHDL 13 SUMMARY In this chapter, we have had a basic introduction to VHDL and how it can be used to model the be ...

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Chapter 2 Behavioral Modeling In Chapter 1, we discussed different modeling techniques and touched briefly on behavioral modelin ...

16 Chapter Two Introduction to Behavioral Modeling The signal assignment statement is the most basic form of behavioral modeling ...

Behavioral Modeling 17 A B C Figure 2-1 AND Gate Symbol. END and2_behav; The AND gate has two inputs a, band one output c, as sh ...

18 Chapter Two I0 I1 A B Q MUX4 I3 I2 Figure 2-2 Mux4 Symbol. q <= i2 AFTER 10 ns WHEN 2, q <= i3 AFTER 10 ns WHEN 3, q &l ...

Behavioral Modeling 19 ABQ 00I0 10I1 01I2 11I3 Figure 2-3 Mux Functional Table. matches does the assign, and the other matching ...

20 Chapter Two based on the sophistication of the synthesis tool and the constraints put on the design. Transport Versus Inertia ...

Behavioral Modeling 21 A B 0 10 20 30 40 AB Delay = 20 ns Figure 2-4 Inertial Delay Buffer Waveforms. event at 30 nanoseconds di ...