【正文】 系統(tǒng)時(shí)鐘 start:in std_logic。use ieee。all。提高系統(tǒng)的可靠性， 設(shè)計(jì)中在LED驅(qū)動(dòng)和位驅(qū)動(dòng)上分別增加了電流驅(qū)動(dòng)器件ULN2803和2SC1015。電力系統(tǒng)將增加不穩(wěn)定因素。接入設(shè)備別針報(bào)告文件，利用現(xiàn)有資源和使用該設(shè)備。系統(tǒng)高層示意圖如圖4所示。 End if。If (count : 101 or count= 001), then data (0) = 39。從圖樣和同步模擬可以看出上述程序，并把有關(guān)數(shù)據(jù)顯示，并產(chǎn)生一個(gè)選擇性同步信號(hào)。 Sound IF。 8 229柜臺(tái)都是用這里提供同步脈沖， VHDL的程序如下：CIkl_label:PROCESS (scp) BEGIN IF scp 39。會(huì)在眼睛中留下閃爍顯示的印象。計(jì)算機(jī)用于模仿AF信號(hào)，在這里和建立一個(gè)半隨機(jī)的信號(hào)，當(dāng)累計(jì)了9個(gè)多或半信號(hào) 1 ，進(jìn)行累積的調(diào)整。變量計(jì)數(shù)器變量的引入。 圖表2Starting mileage (km) DIP switches (three) 000 001 010 011 100 101 110 111 計(jì)程模塊帶有開(kāi)始 / 復(fù)位終端。因此，設(shè)計(jì)圖稿要二進(jìn)制狀態(tài)跳轉(zhuǎn)，從1010跳轉(zhuǎn)至1111超過(guò)六次計(jì)數(shù)。計(jì)程模塊是一個(gè)10個(gè)規(guī)模的，除了一個(gè)計(jì)數(shù)功能。CLA是分頻器電路，占空比通過(guò)datal （ x ）的調(diào)整分頻器，并與啟動(dòng) / 復(fù)位終端（串行復(fù)位） 。使100多種不同型號(hào)分別給予出租車行的每一個(gè)脈沖，通過(guò)提供預(yù)制分頻器 ，以完成頻率系數(shù)。 （ 4 ）解碼器/動(dòng)態(tài)掃描距離與成本會(huì)后動(dòng)態(tài)數(shù)值譯碼數(shù)碼掃描管的驅(qū)動(dòng)方式. （ 5 ） LED顯示屏，將4公里和分帳與LED顯示屏（三個(gè)整數(shù)和一個(gè)小數(shù)）.2 模塊設(shè)計(jì)出租車計(jì)價(jià)器由以下模塊構(gòu)成，即模式選擇模塊，計(jì)量模塊，譯碼和動(dòng)態(tài)掃描模塊，模塊化設(shè)計(jì)整個(gè)系統(tǒng)，準(zhǔn)備先用V HDL模塊，然后頂層框圖將各功能模塊聯(lián)系起來(lái)。不同型號(hào)其車輪的直徑各不相同，通過(guò)一個(gè)選擇開(kāi)關(guān)模式作出選擇。+, 器件構(gòu)成該數(shù)字系統(tǒng)的設(shè)計(jì)思想和實(shí)現(xiàn)過(guò)程 ,計(jì)費(fèi)模塊,譯碼動(dòng)態(tài)掃描模塊等的設(shè)計(jì)方法與技巧.關(guān)鍵詞：出租車計(jì)價(jià)器 CPLD/fpga 硬件描述語(yǔ)言max+plus數(shù)字系統(tǒng) 隨著電子設(shè)計(jì)自動(dòng)化技術(shù)的快速發(fā)展，電子系統(tǒng)的設(shè)計(jì)技術(shù)和工具，經(jīng)歷了一場(chǎng)深刻的變化，出現(xiàn)了大規(guī)模的可編程邏輯器件，極大的方便了設(shè)計(jì)者。mixedtheprotocolCPLDConfigurationtheSynthesize[7]CPLDCPLDand[5]CPLDDataacquisitionanddevelopment[2]Verilogseries 162。 starting to realize that every kilometer. Vehicle fee increases and the length of prefabricated parameters (such as : 3 km charge yuan, yuan / km。 Display Module (hereinafter referred SHOW) Packaging Figure 4. This module is used by the two processes, and procedures in order to implement the process, a process which triggered a second resolution process. Integrated 3 Module FBI Functional module design has been pleted, Segments II use of the graphic editor (Graphic Editor) to the functional module (. sym) link. Because there Mile module Burr, it is not directly linked to and after class. portal of the output pulse signal delay circuit, with the original signal phase and the method can remove burrs. System toplevel schematic diagram shown in Figure 4. Chip definition can be directly edited. Editor in FloorPlan pin documents or under. Pins plete definition chosen device (EPM7128SIC8415), the translation after generation. Sof that. Pofreports and documents. . Access device pins report documents the use of available resources and the use of the device. Replacement of the device make it appropriate to achieve optimal allocation of resources. The general principle is to choose the device system resources used by the devices should not exceed 80% of its resources, in excess of 90%. Power system will increase instability. From the design of this device : the importation of some note in the report, only 16 output pins with the chip resource utilization was only 51%. have greater room for expansion. Figure 4 hardware design shows The design of the CP TaxiMeter counting pulses from the wheel speed sensor (dry spring).Pulse shaping evacuation counter on the device。one39。 Sound IF。 Of these, data (4) advanced to the semiplace mark. Start value and super price increases set up parameters as shown in Table 3 and Table 4. Billing Module (hereinafter referred MONEY) Packaging Figure4. Table 3 installed starting price Starting price (s) DIP switches (three) 001 010 011 100 101 110 111 Table 4 super price plus set up fees Super price increases (yuan) DIP switches (2) 00 01 10 11 Module By paragraph 107 of the LED digital display module and dynamic management decoding scan showed two ponents. paragraph 107 LED decoding digital control This design is used in paragraph 107 of a total digital cathode tube, in accordance with paragraph 107, 16 and 229 the number of code table shows the correlation between When_Else With_Select or VHDL language can be used to facilitate the achievement of their decoding. Figure 2 dynamic scanning display Dynamic scanning using the human visual staying principle,if not less than 24Hz frequency scanning. Eye on the scintillating display scanning pulse of the system by providing the corresponding external scanning signal circuit design, the key lies with the EC shows that he gathers data in the timing. Therefore circuit must provide synchronous pulse signal. Eight 229 counters are used here to provide synchronization pulse,VHDL procedures as follows: CIkl_label:PROCESS (scp) BEGIN IF scp 39。 Log module carries the start / Reset terminal. With Select use the same parameters of prefabricated language. Milestone start and switches relationship, as shown in table 2. Log Module (hereinafter referred Mile) Packaging Figure 4. Table 2 Starting mileage (km) DIP switches (three) 000 001 010 011 100 101 110 111 Billing Module Billing module is a scale of 10, the addition of variable step counter. The module switch prefabricated step, when certain parameters change prefabricated step. Billing module will also reduce the use of nonBCD, but not for one step. Thus, in nonpressed BCD adder to be adjusted Otherwise, it could result in over or exceed preset parameters higher than the wrong way. Computer used to imitate the AF signs here and in the establishment of a semi carry their signs, When cumulative and carry more than 9 or semi signs of 1, and the cumulative adjustment. If datal (3 downto 0), nine or datal (4) = 39。感謝你在畢業(yè)設(shè)計(jì)期間給與我的悉心指導(dǎo)和關(guān)懷！你求學(xué)的嚴(yán)謹(jǐn)態(tài)度、孜孜不倦的探索精神，令我受益終生。這樣設(shè)計(jì)可以節(jié)省四個(gè)數(shù)碼管。也存在很大的不足，靈活性比較差，不便于升級(jí)。導(dǎo)致后來(lái)無(wú)法完成程序編寫。結(jié)束語(yǔ)本次設(shè)計(jì)中我做了以下工作,收集資料，方案論證到方案確定并按確定方案進(jìn)行概要設(shè)計(jì)。該設(shè)計(jì)的前期工作是圍繞現(xiàn)有的出租車計(jì)費(fèi)器，從它的軟件方面做了深入細(xì)致的分析，然后再根據(jù)論文要求進(jìn)行設(shè)計(jì)工作，在本次設(shè)計(jì)中我實(shí)現(xiàn)了現(xiàn)有出租車計(jì)費(fèi)器的基本功能(即計(jì)費(fèi)，計(jì)時(shí)，計(jì)程及顯示功能)，基本達(dá)到了這次畢業(yè)設(shè)計(jì)的基本要求。 end if。cha2=c2。min0=m0。 else min1=39。 cha3=0000。 then min1=0000。event and f_1=39。它可以根據(jù)需要在價(jià)格、時(shí)間、路程三者之間互相轉(zhuǎn)換。（2）計(jì)程部分的波形仿真圖如圖可以用圖5－12所示：當(dāng)k0計(jì)數(shù)達(dá)到9時(shí)k1（即里程的十位數(shù)變?yōu)?）圖5－12計(jì)程部分波形仿真圖譯碼顯示輸出模塊是建立在內(nèi)部系統(tǒng)和觀測(cè)人之間的橋梁。 end if。039。039。圖5－10計(jì)時(shí)部分的波形仿真圖3）計(jì)程部分：對(duì)當(dāng)前行進(jìn)過(guò)程中所走的公里數(shù)進(jìn)行計(jì)