作為嵌入式系統(tǒng)主控單元——單片機(jī),其軟件往往是一個(gè)微觀的實(shí)時(shí)操作系統(tǒng),且大部分是為某種應(yīng)用而專門(mén)設(shè)計(jì)的。系統(tǒng)程序有實(shí)時(shí)過(guò)程控制或?qū)崟r(shí)信息處理的能力,要求能夠及時(shí)響應(yīng)隨機(jī)發(fā)生的外部事件并對(duì)該事件做出快速處理。而分時(shí)操作系統(tǒng)卻是把CPU的時(shí)間劃分成長(zhǎng)短基本相同的時(shí)間區(qū)間,即“時(shí)間片”,通過(guò)操作系統(tǒng)的管理,把這些時(shí)間片依次輪流地分配給各個(gè)用戶使用。如果某個(gè)作業(yè)在時(shí)間片結(jié)束之前,整個(gè)任務(wù)還沒(méi)有完成,那么該作業(yè)就被暫停下來(lái),放棄CPU,等待下一輪循環(huán)再繼續(xù)做。此時(shí)CPU又分配給另一個(gè)作業(yè)去使用。由于計(jì)算機(jī)的處理速度很快,只要時(shí)間片的間隔取得適當(dāng),那么一個(gè)用戶作業(yè)從用完分配給它的一個(gè)時(shí)間片到獲得下一個(gè)CPU時(shí)間片,中間有所“停頓”;但用戶察覺(jué)不出來(lái),好像整個(gè)系統(tǒng)全由它“獨(dú)占”似的。分時(shí)操作系統(tǒng)主要具有以下3個(gè)特點(diǎn):① 多路性。用戶通過(guò)各自的終端,可以同時(shí)使用一個(gè)系統(tǒng)。② 及時(shí)性。用戶提出的各種要求,能在較短或可容忍的時(shí)間內(nèi)得到響應(yīng)和處理。③ 獨(dú)占性。在分時(shí)系統(tǒng)中,雖然允許多個(gè)用戶同時(shí)使用一個(gè)CPU,但用戶之間操作獨(dú)立,互不干涉。分時(shí)操作系統(tǒng)主要是針對(duì)小型機(jī)以上的計(jì)算機(jī)提出的。一般而言,微處理器(MPU)驅(qū)動(dòng)的通用計(jì)算機(jī),系統(tǒng)設(shè)計(jì)人員對(duì)每一臺(tái)的最終具體應(yīng)用都是不得而知的,因此,在價(jià)格允許的情況下,硬件設(shè)計(jì)務(wù)求CPU時(shí)鐘盡可能的快;計(jì)算及管理能力盡可能的強(qiáng);程序和數(shù)據(jù)存儲(chǔ)器的容量盡可能的大;各種計(jì)算機(jī)外設(shè)的配接盡可能的詳盡等等,特別是采用分時(shí)操作系統(tǒng)的機(jī)器,因?yàn)槭且粰C(jī)多用戶的管理系統(tǒng),它的要求就更高了。相對(duì)而言,微控制器(MCU)俗稱單片機(jī),是一個(gè)單片集成系統(tǒng),它將這些或那些計(jì)算機(jī)所需的外設(shè),諸如程序和數(shù)據(jù)存儲(chǔ)器、端口以及有關(guān)的子系統(tǒng)集成到一片芯片上。從硬件上,單片機(jī)系統(tǒng)與采用分時(shí)操作系統(tǒng)的計(jì)算機(jī)系統(tǒng)是無(wú)法比擬的。但是,在單片機(jī)系統(tǒng)的設(shè)計(jì)中,設(shè)計(jì)人員對(duì)其最終具體應(yīng)用是一清二楚的,它的使用環(huán)境相對(duì)是單一固定的。所控制的過(guò)程的可預(yù)見(jiàn)性為分時(shí)系統(tǒng)思想的實(shí)現(xiàn)提供了可能性。具體一點(diǎn)就是:雖然單片機(jī)的CPU速度較低,但其任務(wù)是可預(yù)見(jiàn)的,這樣作業(yè)調(diào)度將變得簡(jiǎn)單而無(wú)須占用很多的CPU時(shí)間,同時(shí)“時(shí)間片”的設(shè)計(jì)是具體而有針對(duì)性的,因此可變得很有效。一、單片機(jī)分時(shí)系統(tǒng)的設(shè)計(jì)單片機(jī)系統(tǒng)往往是一個(gè)嵌入式的控制系統(tǒng),因此目前絕大部分的單片機(jī)系統(tǒng)還是一實(shí)時(shí)系統(tǒng)。能夠真正體現(xiàn)分時(shí)系統(tǒng)的設(shè)計(jì)思想的往往是那些多路重復(fù)檢測(cè)控制系統(tǒng)。即便是在這些多路重復(fù)檢測(cè)控制系統(tǒng)中,它的實(shí)時(shí)性也是非常重要的。也就是說(shuō),在單片機(jī)系統(tǒng)中應(yīng)用了分時(shí)系統(tǒng)設(shè)計(jì)思想,但其及時(shí)性應(yīng)首先進(jìn)行考慮。
標(biāo)簽: 分時(shí)操作系統(tǒng) 中的實(shí)現(xiàn) 單片機(jī)編程
上傳時(shí)間: 2013-12-23
上傳用戶:佳期如夢(mèng)
摘要: 本文介紹了L ED 顯示屏常規(guī)型驅(qū)動(dòng)電路的設(shè)計(jì)方式及其存在的缺陷, 提出了簡(jiǎn)單的L ED 顯示屏恒流驅(qū)動(dòng)方式及電路的實(shí)現(xiàn)。關(guān)鍵詞:L ED 顯示屏 動(dòng)態(tài)掃描 驅(qū)動(dòng)電路中圖分類號(hào): TN 873+ . 93 文獻(xiàn)標(biāo)識(shí)碼:A 文章編號(hào): 1005- 9490(2001) 03- 0252- 051 引 言 L ED 顯示屏是80 年代后期在全球迅速發(fā)展起來(lái)的新型信息顯示媒體, 它利用發(fā)光二極管構(gòu)成的點(diǎn)陣模塊或像素單元, 組成大面積顯示屏幕, 以其可靠性高、使用壽命、環(huán)境適應(yīng)能力強(qiáng)、性能價(jià)格比高、使用成本低等特點(diǎn), 在信息顯示領(lǐng)域已經(jīng)得到了非常廣泛的應(yīng)用[ 1 ]。L ED 顯示屏主要包括發(fā)光二極管構(gòu)成的陣列、驅(qū)動(dòng)電路、控制系統(tǒng)及傳輸接口和相應(yīng)的應(yīng)用軟件等, 其中驅(qū)動(dòng)電路設(shè)計(jì)的好壞, 對(duì)L ED 顯示屏的顯示效果、制作成本及系統(tǒng)的運(yùn)行性能起著很重要的作用。所以, 設(shè)計(jì)一種既能滿足控制驅(qū)動(dòng)的要求, 同時(shí)使用器件少、成本低的控制驅(qū)動(dòng)電路是很有必要的。本文就常規(guī)型驅(qū)動(dòng)電路的設(shè)計(jì)作些分析并提出恒流驅(qū)動(dòng)電路的設(shè)計(jì)方式。2 L ED 顯示屏常規(guī)驅(qū)動(dòng)電路的設(shè)計(jì) L ED 顯示屏驅(qū)動(dòng)電路的設(shè)計(jì), 與所用控制系統(tǒng)相配合, 通常分為動(dòng)態(tài)掃描型驅(qū)動(dòng)及靜態(tài)鎖存型驅(qū)動(dòng)二大類。以下就動(dòng)態(tài)掃描型驅(qū)動(dòng)電路的設(shè)計(jì)為例為進(jìn)行分析:動(dòng)態(tài)掃描型驅(qū)動(dòng)方式是指顯示屏上的4 行、8 行、16 行等n 行發(fā)光二極管共用一組列驅(qū)動(dòng)寄存器, 通過(guò)行驅(qū)動(dòng)管的分時(shí)工作, 使得每行L ED 的點(diǎn)亮?xí)r間占總時(shí)間的1ön , 只要每行的刷新速率大于50 Hz, 利用人眼的視覺(jué)暫留效應(yīng), 人們就可以看到一幅完整的文字或畫(huà)面[ 2 ]。常規(guī)型驅(qū)動(dòng)電路的設(shè)計(jì)一般是用串入并出的通用集成電路芯片如74HC595 或MC14094 等作為列數(shù)據(jù)鎖存, 以8050 等小功率N PN 三極管為列驅(qū)動(dòng), 而以達(dá)林頓三極管如T IP127 等作為行掃描管, 其電路如圖1 所示。
標(biāo)簽: LED 顯示屏 恒流驅(qū)動(dòng) 電路設(shè)計(jì)
上傳時(shí)間: 2014-02-19
上傳用戶:lingzhichao
PIC系列單片機(jī)手冊(cè) 第1 章 簡(jiǎn)介 1-1簡(jiǎn)介 ................................................................................................................................................................. 1-2本手冊(cè)的宗旨 ................................................................................................................................................... 1-3器件結(jié)構(gòu) .......................................................................................................................................................... 1-4開(kāi)發(fā)支持 .......................................................................................................................................................... 1-6器件種類 .......................................................................................................................................................... 1-7格式和符號(hào)的約定 ......................................................................................................................................... 1-12相關(guān)文檔 ........................................................................................................................................................ 1-14相關(guān)應(yīng)用筆記 ................................................................................................................................................. 1-17版本歷史 ........................................................................................................................................................ 1-18第2 章 振蕩器 2-1簡(jiǎn)介 ................................................................................................................................................................. 2-2振蕩器配置 ...................................................................................................................................................... 2-2晶體振蕩器 / 陶瓷諧振器 ................................................................................................................................. 2-4外部RC 振蕩器 ............................................................................................................................................. 2-124MHz 內(nèi)部 RC 振蕩器 ................................................................................................................................... 2-13休眠模式對(duì)片內(nèi)振蕩器的影響 ........................................................................................................................ 2-17器件復(fù)位對(duì)片內(nèi)振蕩器的影響 ........................................................................................................................ 2-17設(shè)計(jì)技巧 ........................................................................................................................................................ 2-18相關(guān)應(yīng)用筆記 ................................................................................................................................................. 2-19版本歷史 ........................................................................................................................................................ 2-20第3 章 復(fù)位 3-1簡(jiǎn)介 ................................................................................................................................................................. 3-2上電復(fù)位、上電延時(shí)定時(shí)器、 起振定時(shí)器、欠壓復(fù)位和奇偶校驗(yàn)錯(cuò)誤復(fù)位 ...................................................... 3-4寄存器和狀態(tài)位的值 ...................................................................................................................................... 3-10設(shè)計(jì)技巧 ........................................................................................................................................................ 3-16相關(guān)應(yīng)用筆記 ................................................................................................................................................. 3-17版本歷史 ........................................................................................................................................................ 3-18 第4 章 架構(gòu) 4-1簡(jiǎn)介 ................................................................................................................................................................. 4-2時(shí)序圖/ 指令周期 ............................................................................................................................................ 4-5指令流/ 流水線 ................................................................................................................................................ 4-6I/O 端口描述 .................................................................................................................................................... 4-7設(shè)計(jì)技巧 ........................................................................................................................................................ 4-12相關(guān)應(yīng)用筆記 ................................................................................................................................................. 4-13版本歷史 ........................................................................................................................................................ 4-14 第5 章 CPU 和ALU 5-1簡(jiǎn)介 ................................................................................................................................................................. 5-2指令的一般格式 ............................................................................................................................................... 5-4中央處理單元(CPU) .................................................................................................................................... 5-4指令時(shí)鐘 .......................................................................................................................................................... 5-4算術(shù)邏輯單元(ALU) .................................................................................................................................... 5-5狀態(tài)寄存器 ...................................................................................................................................................... 5-6OPTION_REG 寄存器 ..................................................................................................................................... 5-8電源控制寄存器 ............................................................................................................................................... 5-9設(shè)計(jì)技巧 ........................................................................................................................................................ 5-10相關(guān)應(yīng)用筆記 ................................................................................................................................................. 5-11版本歷史 ........................................................................................................................................................ 5-12第6 章 存儲(chǔ)器構(gòu)成 6-1簡(jiǎn)介 ................................................................................................................................................................. 6-2程序存儲(chǔ)器構(gòu)成 ............................................................................................................................................... 6-2數(shù)據(jù)存儲(chǔ)器構(gòu)成 ............................................................................................................................................... 6-8初始化 ........................................................................................................................................................... 6-14設(shè)計(jì)技巧 ........................................................................................................................................................ 6-16相關(guān)應(yīng)用筆記 ................................................................................................................................................. 6-17版本歷史 ........................................................................................................................................................ 6-18第7 章 數(shù)據(jù)EEPROM 7-1簡(jiǎn)介 ................................................................................................................................................................. 7-2控制寄存器 ...................................................................................................................................................... 7-3EEADR ............................................................................................................................................................ 7-4EECON1 和EECON2 寄存器 .......................................................................................................................... 7-4從EEPROM 數(shù)據(jù)存儲(chǔ)器中讀數(shù)據(jù) .................................................................................................................... 7-5向EEPROM 數(shù)據(jù)存儲(chǔ)器中寫(xiě)數(shù)據(jù) .................................................................................................................... 7-5寫(xiě)校驗(yàn) ............................................................................................................................................................. 7-6誤寫(xiě)操作保護(hù) ................................................................................................................................................... 7-7代碼保護(hù)配置下的數(shù)據(jù)EEPROM 操作 ............................................................................................................. 7-7初始化 ............................................................................................................................................................. 7-7設(shè)計(jì)技巧 .......................................................................................................................................................... 7-8相關(guān)應(yīng)用筆記 ................................................................................................................................................... 7-9版本歷史 ........................................................................................................................................................ 7-10第8 章 中斷 8-1簡(jiǎn)介 ................................................................................................................................................................. 8-2控制寄存器 ...................................................................................................................................................... 8-5中斷響應(yīng)延時(shí) ................................................................................................................................................. 8-10INT 和外部中斷 .............................................................................................................................................. 8-10中斷的現(xiàn)場(chǎng)保護(hù) ............................................................................................................................................. 8-11初始化 ........................................................................................................................................................... 8-14設(shè)計(jì)技巧 ........................................................................................................................................................ 8-16相關(guān)應(yīng)用筆記 ................................................................................................................................................. 8-17版本歷史 ........................................................................................................................................................ 8-18第9 章 I/O 端口 9-1簡(jiǎn)介 ................................................................................................................................................................. 9-2PORTA 和TRISA 寄存器 ................................................................................................................................ 9-4PORTB 和TRISB 寄存器 ................................................................................................................................ 9-6PORTC 和TRISC 寄存器 ................................................................................................................................ 9-8PORTD 和TRISD 寄存器 ................................................................................................................................ 9-9PORTE 和TRISE 寄存器 ............................................................................................................................... 9-10PORTF 和 TRISF 寄存器 ............................................................................................................................... 9-11PORTG 和TRISG 寄存器 .............................................................................................................................. 9-12GPIO 和TRISGP 寄存器 ............................................................................................................................... 9-13I/O 編程注意事項(xiàng) ........................................................................................................................................... 9-14初始化 ........................................................................................................................................................... 9-16設(shè)計(jì)技巧 ........................................................................................................................................................ 9-17相關(guān)應(yīng)用筆記 ................................................................................................................................................. 9-19版本歷史 ........................................................................................................................................................ 9-20第10 章 并行從動(dòng)端口 10-1簡(jiǎn)介 ............................................................................................................................................................... 10-2控制寄存器 .................................................................................................................................................... 10-3操作 ............................................................................................................................................................... 10-4休眠模式下的操作 ......................................................................................................................................... 10-5復(fù)位的影響 .................................................................................................................................................... 10-5PSP 波形 ....................................................................................................................................................... 10-5設(shè)計(jì)技巧 ........................................................................................................................................................ 10-6相關(guān)應(yīng)用筆記 ................................................................................................................................................. 10-7版本歷史 ........................................................................................................................................................ 10-8 第11 章 TIMER0 11-1簡(jiǎn)介 ............................................................................................................................................................... 11-2控制寄存器 .................................................................................................................................................... 11-3操作 ............................................................................................................................................................... 11-4TMR0 中斷 .................................................................................................................................................... 11-5Timer0 外部時(shí)鐘的使用 ................................................................................................................................. 11-6TMR0 的預(yù)分頻器 ......................................................................................................................................... 11-7設(shè)計(jì)技巧 ...................................................................................................................................................... 11-10相關(guān)應(yīng)用筆記 ............................................................................................................................................... 11-11版本歷史 ...................................................................................................................................................... 11-12第12 章 TIMER1 12-1簡(jiǎn)介 ............................................................................................................................................................... 12-2控制寄存器 .................................................................................................................................................... 12-3Timer1 工作在定時(shí)器模式 ..............................................................................................................................12-4Timer1 工作在同步計(jì)數(shù)器模式 ....................................................................................................................... 12-4Timer1 工作在異步計(jì)數(shù)器模式 ....................................................................................................................... 12-5Timer1 振蕩器 ............................................................................................................................................... 12-7休眠操作 ........................................................................................................................................................ 12-9用CCP 觸發(fā)器的輸出將Timer1 復(fù)位 ............................................................................................................. 12-9Timer1 寄存器(TMR1H:TMR1L)的復(fù)位 .................................................................................................... 12-9Timer1 預(yù)分頻器 ............................................................................................................................................ 12-9初始化 ......................................................................................................................................................... 12-10設(shè)計(jì)技巧 ...................................................................................................................................................... 12-12相關(guān)應(yīng)用筆記 ............................................................................................................................................... 12-13版本歷史 ...................................................................................................................................................... 12-14第13 章 TIMER2 13-1簡(jiǎn)介 ............................................................................................................................................................... 13-2控制寄存器 .................................................................................................................................................... 13-3定時(shí)器時(shí)鐘源 ................................................................................................................................................. 13-4定時(shí)器TMR2 和PR2 周期寄存器 .................................................................................................................. 13-4TMR2 匹配輸出 ............................................................................................................................................. 13-4將Timer2 的預(yù)分頻器和后分頻器清零 ........................................................................................................... 13-4休眠操作 ........................................................................................................................................................ 13-4初始化 ........................................................................................................................................................... 13-5設(shè)計(jì)技巧 ........................................................................................................................................................ 13-6相關(guān)應(yīng)用筆記 ................................................................................................................................................. 13-7版本歷史 ........................................................................................................................................................ 13-8第14 章 比較/ 捕捉/ 脈寬調(diào)制(CCP) 14-1簡(jiǎn)介 ............................................................................................................................................................... 14-2控制寄存器 .................................................................................................................................................... 14-3捕捉模式 ........................................................................................................................................................ 14-4比較模式 ........................................................................................................................................................ 14-6PWM 模式 ..................................................................................................................................................... 14-8初始化 ......................................................................................................................................................... 14-12設(shè)計(jì)技巧 ...................................................................................................................................................... 14-15相關(guān)應(yīng)用筆記 ............................................................................................................................................... 14-17版本歷史 ...................................................................................................................................................... 14-18第15 章 同步串行口(SSP) 15-1簡(jiǎn)介 ............................................................................................................................................................... 15-2控制寄存器 .................................................................................................................................................... 15-3SPITM 模式 .................................................................................................................................................... 15-6SSP 模塊的I2CTM 操作 ............................................................................................................................... 15-16初始化 ......................................................................................................................................................... 15-26設(shè)計(jì)技巧 ...................................................................................................................................................... 15-28相關(guān)應(yīng)用筆記 ............................................................................................................................................... 15-29版本歷史 ...................................................................................................................................................... 15-30第16 章 基本同步串行口(BSSP) 16-1簡(jiǎn)介 ............................................................................................................................................................... 16-2控制寄存器 .................................................................................................................................................... 16-3SPITM 模式 .................................................................................................................................................... 16-6SSP 模塊 的I2CTM 操作 ............................................................................................................................... 16-15初始化 ......................................................................................................................................................... 16-23設(shè)計(jì)技巧 ...................................................................................................................................................... 16-24相關(guān)應(yīng)用筆記 ............................................................................................................................................... 16-25版本歷史 ...................................................................................................................................................... 16-26第17 章 主同步串行口(MSSP) 17-1簡(jiǎn)介 ............................................................................................................................................................... 17-2控制寄存器 .................................................................................................................................................... 17-4SPITM 模式 .................................................................................................................................................... 17-9SSP 模塊的 I2C™ 操作 ............................................................................................................................... 17-18I2CTM 總線的連接注意事項(xiàng) ........................................................................................................................... 17-56初始化 ......................................................................................................................................................... 17-57設(shè)計(jì)技巧 ...................................................................................................................................................... 17-58相關(guān)應(yīng)用筆記 ............................................................................................................................................... 17-59版本歷史 ...................................................................................................................................................... 17-60第18 章 USART 18-1簡(jiǎn)介 ............................................................................................................................................................... 18-2控制寄存器 .................................................................................................................................................... 18-3USART 波特率發(fā)生器(BRG) ..................................................................................................................... 18-5USART 異步工作模式 ................................................................................................................................... 18-8USART 同步主控模式 .................................................................................................................................. 18-15USART 同步從動(dòng)模式 ................................................................................................................................. 18-19初始化 ......................................................................................................................................................... 18-21設(shè)計(jì)技巧 ...................................................................................................................................................... 18-22相關(guān)應(yīng)用筆記 ............................................................................................................................................... 18-23版本歷史 ...................................................................................................................................................... 18-24第19 章 參考電壓模塊 19-1簡(jiǎn)介 ............................................................................................................................................................... 19-2控制寄存器 .................................................................................................................................................... 19-3配置參考電壓 ................................................................................................................................................. 19-4參考電壓精度 ................................................................................................................................................. 19-5休眠模式下的操作 ......................................................................................................................................... 19-5復(fù)位的影響 .................................................................................................................................................... 19-5連接注意事項(xiàng) ................................................................................................................................................. 19-6初始化 ........................................................................................................................................................... 19-7設(shè)計(jì)技巧 ........................................................................................................................................................ 19-8相關(guān)應(yīng)用筆記 ................................................................................................................................................. 19-9版本歷史 ...................................................................................................................................................... 19-10第20 章 比較器 20-1簡(jiǎn)介 ............................................................................................................................................................... 20-2控制寄存器 .................................................................................................................................................... 20-3設(shè)置比較器模式 ............................................................................................................................................. 20-4比較器工作原理 ............................................................................................................................................. 20-6比較器參考源 ................................................................................................................................................. 20-6比較器的響應(yīng)時(shí)間 ......................................................................................................................................... 20-8比較器輸出 .................................................................................................................................................... 20-8比較器中斷 .................................................................................................................................................... 20-9休眠狀態(tài)下比較器的操作 ............................................................................................................................... 20-9復(fù)位的影響 .................................................................................................................................................... 20-9模擬輸入連接方式注意事項(xiàng) .......................................................................................................................... 20-10初始化 ......................................................................................................................................................... 20-11設(shè)計(jì)技巧 ...................................................................................................................................................... 20-12相關(guān)應(yīng)用筆記 ............................................................................................................................................... 20-13版本歷史 ...................................................................................................................................................... 20-14第21 章 8 位A/D 轉(zhuǎn)換器 21-1簡(jiǎn)介 ............................................................................................................................................................... 21-2控制寄存器 .................................................................................................................................................... 21-3操作 ............................................................................................................................................................... 21-5A/D 采集時(shí)間要求 .......................................................................................................................................... 21-6A/D 轉(zhuǎn)換時(shí)鐘的選擇 ...................................................................................................................................... 21-8配置模擬輸入端口 ......................................................................................................................................... 21-9A/D 轉(zhuǎn)換 ...................................................................................................................................................... 21-10休眠期間的A/D 轉(zhuǎn)換 ................................................................................................................................... 21-12A/D 精度/ 誤差 ............................................................................................................................................ 21-13復(fù)位對(duì)A/D 轉(zhuǎn)換的影響 ................................................................................................................................ 21-13CCP 觸發(fā)器的使用 ...................................................................................................................................... 21-14連接注意事項(xiàng) ............................................................................................................................................... 21-14傳遞函數(shù) ...................................................................................................................................................... 21-14初始化 ......................................................................................................................................................... 21-15設(shè)計(jì)技巧 ...................................................................................................................................................... 21-16相關(guān)應(yīng)用筆記 ............................................................................................................................................... 21-17版本歷史 ...................................................................................................................................................... 21-18第22 章 基本型8 位A/D 轉(zhuǎn)換器 22-1簡(jiǎn)介 ............................................................................................................................................................... 22-2控制寄存器 .................................................................................................................................................... 22-3A/D 采集時(shí)間要求 .......................................................................................................................................... 22-6A/D 轉(zhuǎn)換時(shí)鐘的選擇 ...................................................................................................................................... 22-8配置模擬輸入端口 ....................................................................................................................................... 22-10A/D 轉(zhuǎn)換 ...................................................................................................................................................... 22-11休眠期間的A/D 轉(zhuǎn)換 ................................................................................................................................... 22-14A/D 轉(zhuǎn)換精度/ 誤差 ..................................................................................................................................... 22-15復(fù)位對(duì)A/D 轉(zhuǎn)換的影響 ................................................................................................................................ 22-16連接時(shí)的考慮事項(xiàng) ....................................................................................................................................... 22-16傳遞函數(shù) ...................................................................................................................................................... 22-16初始化 ......................................................................................................................................................... 22-17設(shè)計(jì)技巧 ...................................................................................................................................................... 22-18相關(guān)應(yīng)用筆記 ............................................................................................................................................... 22-19版本歷史 ...................................................................................................................................................... 22-20第23 章 10 位A/D 轉(zhuǎn)換器 23-1簡(jiǎn)介 ............................................................................................................................................................... 23-2控制寄存器 .................................................................................................................................................... 23-3操作 ............................................................................................................................................................... 23-5A/D 采集時(shí)間要求 .......................................................................................................................................... 23-6A/D 轉(zhuǎn)換時(shí)鐘的選擇 ...................................................................................................................................... 23-8模擬輸入引腳的設(shè)置 ...................................................................................................................................... 23-9A/D 轉(zhuǎn)換的編程舉例 .................................................................................................................................... 23-10休眠期間的A/D 轉(zhuǎn)換 ................................................................................................................................... 23-14復(fù)位對(duì)A/D 轉(zhuǎn)換的影響 ................................................................................................................................ 23-14A/D 轉(zhuǎn)換精度與誤差 .................................................................................................................................... 23-15連接時(shí)的考慮事項(xiàng) ....................................................................................................................................... 23-16傳遞函數(shù) ...................................................................................................................................................... 23-16初始化 ......................................................................................................................................................... 23-17設(shè)計(jì)技巧 ...................................................................................................................................................... 23-18相關(guān)應(yīng)用筆記 ............................................................................................................................................... 23-19版本歷史 ...................................................................................................................................................... 23-20第24 章 積分型A/D 轉(zhuǎn)換器 24-1簡(jiǎn)介 ............................................................................................................................................................... 24-2控制寄存器 .................................................................................................................................................... 24-3轉(zhuǎn)換過(guò)程 ........................................................................................................................................................ 24-6其它模擬模塊 ............................................................................................................................................... 24-12校準(zhǔn)參數(shù) ...................................................................................................................................................... 24-13設(shè)計(jì)技巧 ...................................................................................................................................................... 24-14相關(guān)應(yīng)用筆記 ............................................................................................................................................... 24-15版本歷史 ...................................................................................................................................................... 24-16第25 章 LCD 25-1簡(jiǎn)介 ............................................................................................................................................................... 25-2控制寄存器 .................................................................................................................................................... 25-3LCD 定時(shí) ....................................................................................................................................................... 25-6LCD 中斷 ..................................................................................................................................................... 25-12像素控制 ...................................................................................................................................................... 25-13電壓發(fā)生器 .................................................................................................................................................. 25-15休眠模式下的操作 ....................................................................................................................................... 25-16復(fù)位的影響 .................................................................................................................................................. 25-17LCD 模塊的設(shè)置 .......................................................................................................................................... 25-17判別比 ......................................................................................................................................................... 25-18LCD 電壓發(fā)生器 .......................................................................................................................................... 25-20對(duì)比度 ......................................................................................................................................................... 25-22LCD 玻璃基板 .............................................................................................................................................. 25-22初始化 ......................................................................................................................................................... 25-23設(shè)計(jì)技巧 ...................................................................................................................................................... 25-24相關(guān)應(yīng)用筆記 ............................................................................................................................................... 25-25版本歷史 ...................................................................................................................................................... 25-26第26 章 看門(mén)狗定時(shí)器與休眠模式 26-1簡(jiǎn)介 ............................................................................................................................................................... 26-2控制寄存器 .................................................................................................................................................... 26-3看門(mén)狗定時(shí)器(WDT)的操作 ....................................................................................................................... 26-4休眠省電模式 ................................................................................................................................................. 26-7初始化 ........................................................................................................................................................... 26-9設(shè)計(jì)技巧 ...................................................................................................................................................... 26-10相關(guān)應(yīng)用筆記 ............................................................................................................................................... 26-11版本歷史 ...................................................................................................................................................... 26-12第27 章 器件配置位 27-1簡(jiǎn)介 ............................................................................................................................................................... 27-2配置字位 ........................................................................................................................................................ 27-4編程校驗(yàn)/ 代碼保護(hù) ....................................................................................................................................... 27-8識(shí)別碼ID 的位置 ........................................................................................................................................... 27-9設(shè)計(jì)技巧 ...................................................................................................................................................... 27-10相關(guān)應(yīng)用筆記 ............................................................................................................................................... 27-11版本歷史 ...................................................................................................................................................... 27-12第28 章 在線串行編程 28-1簡(jiǎn)介 ............................................................................................................................................................... 28-2進(jìn)入在線串行編程模式 .................................................................................................................................. 28-3應(yīng)用電路 ........................................................................................................................................................ 28-4編程器 ........................................................................................................................................................... 28-6編程環(huán)境 ........................................................................................................................................................ 28-6其它優(yōu)點(diǎn) ........................................................................................................................................................ 28-7PICmicro® OTP 型單片機(jī)的現(xiàn)場(chǎng)編程 ............................................................................................................. 28-8FLASH 型 PICmicro® 單片機(jī)的現(xiàn)場(chǎng)編程 ...................................................................................................... 28-10設(shè)計(jì)技巧 ...................................................................................................................................................... 28-12相關(guān)應(yīng)用筆記 ............................................................................................................................................... 28-13版本歷史 ...................................................................................................................................................... 28-14第29 章 指令集 29-1簡(jiǎn)介 ............................................................................................................................................................... 29-2指令格式 ........................................................................................................................................................ 29-4作為源/ 目標(biāo)寄存器的特殊功能寄存器 ........................................................................................................... 29-6Q 周期操作 .................................................................................................................................................... 29-7指令描述 ........................................................................................................................................................ 29-8設(shè)計(jì)技巧 ...................................................................................................................................................... 29-45相關(guān)應(yīng)用筆記 ............................................................................................................................................... 29-47版本歷史 ...................................................................................................................................................... 29-48第30 章 電氣規(guī)范 30-1簡(jiǎn)介 ............................................................................................................................................................... 30-2絕對(duì)最大值 .................................................................................................................................................... 30-3器件選型表 .................................................................................................................................................... 30-4器件電壓規(guī)范 ................................................................................................................................................. 30-5器件電流特性 ................................................................................................................................................. 30-6輸入閾值電平 ................................................................................................................................................. 30-9I/O 電流特性 ................................................................................................................................................ 30-10輸出驅(qū)動(dòng)電壓 ............................................................................................................................................... 30-11I/O 引腳的容性負(fù)載 ..................................................................................................................................... 30-12數(shù)據(jù)EEPROM / 閃存 .................................................................................................................................. 30-13LCD ............................................................................................................................................................. 30-14比較器和參考電壓 ....................................................................................................................................... 30-15時(shí)序參數(shù)符號(hào) ............................................................................................................................................... 30-16外部時(shí)鐘時(shí)序波形圖和時(shí)序要求示例 ............................................................................................................ 30-17上電和復(fù)位時(shí)序波形圖及要求示例 ............................................................................................................... 30-19定時(shí)器Timer0 和Timer1 時(shí)序波形圖及要求示例 ......................................................................................... 30-20CCP 的時(shí)序圖及要求 ................................................................................................................................... 30-21并行從動(dòng)端口 (PSP) 時(shí)序圖及要求 .............................................................................................................. 30-22SSP 和 MSSP SPITM 模式時(shí)序波形圖及要求示例 ....................................................................................... 30-23SSP I2CTM 模式時(shí)序波形圖及要求示例 ........................................................................................................ 30-27MSSP I2CTM 模式時(shí)序波形圖及要求示例 ..................................................................................................... 30-30USART/SCI 時(shí)序波形圖及要求示例 ............................................................................................................. 30-328 位 A/D 時(shí)序波形圖及要求示例 ................................................................................................................... 30-3410 位A/D 時(shí)序波形圖及要求示例 ................................................................................................................. 30-36積分型A/D 時(shí)序波形圖及要求示例 ............................................................................................................... 30-38LCD 時(shí)序波形圖及要求示例 ......................................................................................................................... 30-40相關(guān)應(yīng)用筆記 ............................................................................................................................................... 30-41版本歷史 ...................................................................................................................................................... 30-42第31 章 器件特性 31-1簡(jiǎn)介 ............................................................................................................................................................... 31-2特性和電氣規(guī)范 ............................................................................................................................................. 31-2DC 和AC 特性圖表 ....................................................................................................................................... 31-2版本歷史 ...................................................................................................................................................... 31-22第32 章 開(kāi)發(fā)工具 32-1簡(jiǎn)介 ............................................................................................................................................................... 32-2集成開(kāi)發(fā)環(huán)境(IDE) ................................................................................................................................... 32-3MPLAB® 軟件語(yǔ)言支持 ................................................................................................................................. 32-6MPLAB® SIM 軟件模擬器 ............................................................................................................................... 32-8MPLAB® 硬件仿真器支持 ............................................................................................................................... 32-9MPLAB® 編程器支持 ................................................................................................................................... 32-10輔助工具 ...................................................................................................................................................... 32-11開(kāi)發(fā)板 ......................................................................................................................................................... 32-12針對(duì)其它Microchip 產(chǎn)品的開(kāi)發(fā)工具 ............................................................................................................ 32-14相關(guān)應(yīng)用筆記 ............................................................................................................................................... 32-15版本歷史 ...................................................................................................................................................... 32-16第33 章 代碼開(kāi)發(fā) 33-1版本歷史 ........................................................................................................................................................ 33-2第34 章 附錄 34-1I2CTM 概述...................................................................................................................................................... 34-2LCD 玻璃基板生產(chǎn)商.................................................................................................................................... 34-11改進(jìn)的器件特性............................................................................................................................................ 34-13版本歷史....................................................................................................................................................... 34-19第35 章 術(shù)語(yǔ)表 35-1版本歷史 ...................................................................................................................................................... 35-14目錄
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