【正文】 perature measurements. The system is divided into the following modules: microprocessor core module, LED display module, keyboard module, temperature measurement module, remote data transmission module, power supply module. KEY WORDS: microcontroller, I2C bus, remote data acquisition III 目 錄 摘 要 ........................................................................................................................................... I ABSTRACT ............................................................................................................................... II 1 緒論 ........................................................................................................................................ 1 數(shù)據(jù)采集系統(tǒng)及發(fā)展歷程 ............................................................................................... 1 I2C 總線及優(yōu)點(diǎn) ................................................................................................................ 1 2 系統(tǒng)方案 ................................................................................................................................ 3 系 統(tǒng)方案簡(jiǎn)介 .................................................................................................................. 3 系統(tǒng)總體方案的確定 ...................................................................................................... 3 主控制器方案的選型 ............................................................................................... 3 I2C 擴(kuò)展芯片的選型 ................................................................................................. 4 溫度傳感器的選型 ................................................................................................... 4 LCD 液晶驅(qū)動(dòng)器的選型 ........................................................................................... 5 A/D 轉(zhuǎn)換器的選型 ..................................................................................................... 5 總結(jié) ................................................................................................................................... 5 3 P89LPC922 單片機(jī)及 I2C 接口 ............................................................................................. 6 P89LPC922 單片機(jī)概述 .................................................................................................. 6 芯片內(nèi)部框圖 ........................................................................................................... 6 引腳配置 ................................................................................................................... 7 I/O 口 ................................................................................................................................ 7 I/O 端口配置 .............................................................................................................. 8 準(zhǔn)雙向口輸出配置 ................................................................................................... 8 開漏輸出配置 ........................................................................................................... 8 僅為輸入配置 ........................................................................................................... 8 推挽輸出配置 ........................................................................................................... 9 中斷 .................................................................................................................................. 9 I2C 總線接口 .................................................................................................................... 9 概述 ........................................................................................................................... 9 I2C 特殊功能寄存器描述 ....................................................................................... 10 I2C 操作模式 ........................................................................................................... 12 總結(jié) ................................................................................................................................. 13 4 硬件電路設(shè)計(jì) ...................................................................................................................... 14 單片機(jī)控制電路 ............................................................................................................ 14 IV LED 顯示模塊 ................................................................................................................ 15 遠(yuǎn)程傳輸模塊 ................................................................................................................ 16 電源模塊 ........................................................................................................................ 18 溫度測(cè)量模塊 ................................................................................................................ 18 A/D 轉(zhuǎn)換器 PCF8591 ............................................................................................. 19 溫度傳感器 AD590 ................................................................................................ 19 總結(jié) ................................................................................................................................. 20 5 系統(tǒng)軟件設(shè)計(jì) ...................................................................................................................... 21 MAIN 函數(shù)設(shè)計(jì) ............................................................................................................... 21 I2C 發(fā)送數(shù)據(jù)函數(shù) .......................................................................................................... 22 鍵盤中斷函數(shù) ................................................................................................................ 23 鍵盤處理函數(shù) ................................................................................................................ 23 LED 顯示函數(shù) .........................................................................