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| author | Sven Eisenhauer <sven@sven-eisenhauer.net> | 2023-11-10 15:11:48 +0100 |
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| committer | Sven Eisenhauer <sven@sven-eisenhauer.net> | 2023-11-10 15:11:48 +0100 |
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diff --git a/Bachelor/Digitaltechnik 2/SS07/P6/abel.ex2.html b/Bachelor/Digitaltechnik 2/SS07/P6/abel.ex2.html new file mode 100644 index 0000000..006cd54 --- /dev/null +++ b/Bachelor/Digitaltechnik 2/SS07/P6/abel.ex2.html @@ -0,0 +1,169 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<html><head><title>Finite State Machine (Moore) example: string detector</title> + + + + <meta name="GENERATOR" content="User-Agent: Mozilla/3.0Gold (Macintosh; I; PPC)"> + <meta name="Author" content="J. Van der Spiegel"></head><body> + +<h1 align="center"><i><font size="+1">University of Pennsylvania</font></i> +</h1> + +<center><p><i><font size="+1">Department of Electrical Engineering </font></i><br> +<br> +</p></center> + +<center><p><b>Finite State Machine implemented as a Moore Machine: </b></p></center> + +<center><p><b>a non-resetting sequence recognizer.</b><br> +</p></center> + +<p>The following state diagram (Fig. 1) describes a finite state machine +with one input X and one output Z. The FSM asserts its output Z when it +recognizes the following input bit sequence: "1011". The machine +will keep checking for the proper bit sequence and does not reset to the +initial state after it has recognized the string. As an example the input +string X= "..1011011..." will cause the output to go high twice: +Z = "..0001001.." . The output will asserts only when it is in +state S4 (after having seen the sequence 1011). The FSM is thus a Moore +machine.<br> +<br> +</p> + +<center><p><img src="abel.ex2-Dateien/abel_002.gif" height="94" width="336"></p></center> + +<p>Figure 1: State diagram, describing the sequence detector implemented +as a Moore machine. The number in italics underneath the states indicate +which part of the sequence the state remembers.<br> +</p> + +<p>This state diagram can be described in ABEL code given in Listing 1. +The output is described after the STATE Si: statement. <br> +</p> + +<p><font color="#000000">Listing 1: ABEL source code for the Moore machine +implementation of the sequence detector described in Fig. 1</font><br> +</p> + +<ul> +<p><font size="-1"><font face="Courier"><font color="#000000">module Seqdet2</font></font> +<br> +<font face="Courier"><font color="#000000">Title 'Sequence detector implemented +as Moore machine'<br> +Declarations<br> +"input and output signals</font></font></font></p> + +<p><font size="-1"><font face="Courier"><font color="#000000">X, CLOCK, RST +PIN;</font></font> <br> +<font face="Courier"><font color="#000000">Z PIN istype 'com';</font></font> +<br> +<font face="Courier"><font color="#000000">Q2, Q1, Q0 PIN istype 'reg';</font></font> +</font></p> + +<p><font size="-1"><font face="Courier"><font color="#000000">"State +register declarations</font></font> </font></p> + +<p><font size="-1"><font face="Courier"><font color="#000000">SREG = [Q2,Q1,Q0];</font></font> +<br> +<font face="Courier"><font color="#000000">S0 = [0,0,0];</font></font> +<br> +<font face="Courier"><font color="#000000">S1 = [0,0,1];</font></font> +<br> +<font face="Courier"><font color="#000000">S2 = [0,1,0];</font></font> +<br> +<font face="Courier"><font color="#000000">S3 = [0,1,1];</font></font> +<br> +<font face="Courier"><font color="#000000">S4 = [1,0,0];</font></font></font><br> +</p> + +<p><font face="Courier"><font color="#000000"><font size="-1">Equations<br> +"Definition of the state machine clock signal</font></font></font></p> + +<p><font size="-1"><font face="Courier"><font color="#000000">[Q2,Q1,Q0].AR += RST;</font></font> <br> +<font face="Courier"><font color="#000000">[Q2,Q1,Q0].CLK = CLOCK;</font></font></font><br> +</p> + +<p><font size="-1"><font face="Courier"><font color="#000000">"Define +state diagram</font></font> <br> +<font face="Courier"><font color="#000000">STATE_DIAGRAM SREG</font></font> +</font></p> + +<p><font size="-1"><font face="Courier"><font color="#000000">STATE S0: Z=0;</font></font> +</font></p> + +<ul> +<p><br> +<font size="-1"><font face="Courier"><font color="#000000">IF X THEN S1 ELSE +S0;</font></font> </font></p> +</ul> + +<p><font size="-1"><font face="Courier"><font color="#000000">STATE S1: Z=0;</font></font> +</font></p> + +<ul> +<p><font size="-1"><font face="Courier"><font color="#000000">IF X THEN S1 +ELSE S2;</font></font> </font></p> +</ul> + +<p><font face="Courier"><font color="#000000"><font size="-1">STATE S2: Z=0; +</font></font></font></p> + +<ul> +<p><font size="-1"><font face="Courier"><font color="#000000">IF X THEN S3 +ELSE S0;</font></font> </font></p> +</ul> + +<p><font size="-1"><font face="Courier"><font color="#000000">STATE S3: Z=0;</font></font> +</font></p> + +<ul> +<p><font size="-1"><font face="Courier"><font color="#000000">IF X THEN S4 +ELSE S2;</font></font> </font></p> +</ul> + +<p><font size="-1"><font face="Courier"><font color="#000000">STATE S4: Z=1;</font></font> +</font></p> + +<ul> +<p><font size="-1"><font face="Courier"><font color="#000000">IF X THEN S1 +ELSE S2;</font></font> </font></p> +</ul> + +<p><font face="Courier"><font color="#000000"><font size="-1">end Seqdet2</font></font></font><br> +</p> +</ul> + +<p>The corresponding simulation is shown in Figure 2. </p> + +<center><p><br> +<img src="abel.ex2-Dateien/abel.gif" height="334" width="537"><br> +<br> +</p></center> + +<center><p>Figure 2: Simulation of the sequence detector (for "1011") +described with the state diagram of Fig. 1. (Screen clip from Xilinx XACTstep(TM) +Foundation software)<br> +</p></center> + +<p>One notices that the output asserts after the input sequence 1011 as +specified.<br> +</p> + +<p> +</p><hr width="100%"><font size="-1">Back to ABEL Primer <a href="http://www.ee.upenn.edu/rca/software/abel/abel.primer.html#Contents">Contents</a> +| To to <a href="http://www.ee.upenn.edu/rca/software/xilinx/foundation/commistakes.html">Common +Mistakes</a> list | Go to the <a href="http://www.ee.upenn.edu/rca">EE +Undergraduate Lab</a> Homepage | Go to <a href="http://www.ee.upenn.edu/rca/software/xilinx.html">Xilinx +Lab Tutorial</a> Homepage | Go to the <a href="http://www.ee.upenn.edu/rca/software/xilinx/foundation/foundation.sch1.html">Foundation +Tutorial</a> page | Go to <a href="http://www.seas.upenn.edu/%7Eee200/">EE200 +</a>or <a href="http://www.seas.upenn.edu/%7Eee200/lab/lab.html">EE200 Lab</a> +Homepage |</font><p></p> + +<p> +</p><hr width="100%">Created by J. Van der Spiegel: November 16, 1997. Updated +by J. Van der Spiegel, Nov. 19, 1997.<br> +<p></p> + + +</body></html>
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