基于VHDL數(shù)字頻率計的設計與仿真

目錄
1 緒論 1
1.1 課題簡介 1
1.2 課題研究背景 2
1.3 課題設計意義和目的 3
2 數(shù)字頻率計的綜合設計 5
2.1 設計原理 5
2.2 設計功能 5
2.3 設計思路 6
3 利用VHDL語言設計頻率計 8
3.1 VHDL語言介紹 8
3.2 頻率計的設計程序 9
4 數(shù)字頻率計的仿真及波形分析 15
4.1 MAX+PLUS II軟件簡介 15
4.2 MAX+plus II的文本輸入設計方法 16
4.3 系統(tǒng)設計仿真及波形分析 25
5 小結 32
致謝 33
附錄：頻率計源程序及模塊圖 34
參考文獻 41

摘要：數(shù)字頻率計是數(shù)字電路中的一個典型應用，實際的硬件設計用到的器件較多，連線比較復雜，而且會產(chǎn)生比較大的延時，造成測量誤差、可靠性差。本課題介紹一種運用MAX+PLUSⅡ軟件基于VHDL的采用自頂而下 (up to bottom ) 設計方法實現(xiàn)的數(shù)字頻率計。根據(jù)頻率計的基本原理, 運用自頂向下的設計思想,編程時分別對控制、計數(shù)、鎖存、譯碼等電路模塊進行VHDL文本描述 ,使每個電路模塊以及器件都以文本的形式出現(xiàn) ,然后通過編譯、波形分析、仿真、調(diào)試來完善每個器件的功能。單個器件制作完成后 ,將它們生成庫文件 ,并產(chǎn)生相應的符號,最后用語言將各個已生成庫文件的器件的各個端口連接在一起 ,從而形成了系統(tǒng)主電路的軟件結構。該設計方法與傳統(tǒng)的設計方法相比,具有外圍電路簡單,程序修改靈活和調(diào)試容易等特點,實現(xiàn)數(shù)字系統(tǒng)硬件的軟件化。
關鍵字：VHDL;頻率計; MAX+PLUSⅡ
中圖分類號：TP312

 
Digital frequency meter based on VHDL Design and Simulation

Abstract: Digital frequency meter is a digital circuit in a typical application, the actual hardware design of devices used in more complicated connection, but will have larger delay, caused by measurement error, poor reliability. This issue introduces a use of MAX + PLUS Ⅱ software is based on the use of VHDL top-down (up to bottom) design method to achieve the digital frequency meter. According to the basic principle of frequency meter, using top-down design, and programming the control, respectively, counting, latch, decoder circuit modules such as VHDL text description, so that each circuit module and the device is in text form , and then compile, waveform analysis, simulation, debugging to improve the function of each device. Produced a single device, will they generate library files, and generates a corresponding symbol, the final language will have generated libraries of various devices connected to each port, the main circuit to form the system software structure. The design method and the traditional design method, a simple peripheral circuits, application to modify the characteristics of a flexible and easy to debug, hardware-software implementation of digital systems.
Keywords: VHDL; frequency meter; MAX+PLUSⅡ