【正文】 關(guān)鍵詞 ： U盤； CH375；接口芯片；單片機(jī) Abstract A general purpose interface chip CH37 5 for USB is introduced in this paper． Based On which a new method of Using external single chip microputer to connect with the flash disk is given． Only add one CH375 chip to the single chip microputer s hardware system， the operator can use the program given by the CH375 to read the data from the flash disk and realize the munication between the single chip microputer and the flash disk． This method is very simple and can be operated easily． Keywords： USB； CH375； interface chip； single chip microputer 目 錄 摘 要 ............................................................................................................................................................................ I ABSTRACT ............................................................................................................................................................... II 目 錄 ............................................................................................................................................................................ I 一、緒 論 ....................................................................................................................................................................3 二、 總體方案設(shè)計(jì)與選擇論證 ..............................................................................................................................4 總體設(shè)計(jì)分析 ...................................................................................................................................................4 功能模塊方案設(shè)計(jì)選擇 ..................................................................................................................................4 MCU 的選擇 ..............................................................................................................................................4 CH375 工作方式方案選擇 ......................................................................................................................5 電源選擇 ....................................................................................................................................................5 系統(tǒng)方框圖 .......................................................................................................................................................6 三、硬件設(shè)計(jì)分析 .....................................................................................................................................................7 STC12C5A60AD 單片機(jī)最小系統(tǒng)電路 ........................................................................................................7 STC12C5A60AD 單片機(jī) 簡(jiǎn)介 ..................................................................................................................8 STC12C5A60AD 系列主要性能： ....................................................................................................... 10 7805 三端正電源穩(wěn)壓電路 ....................................................................................................................11 CH375 接口電路 ........................................................................................................................................... 12 USB 總線的通用接口芯片 CH375 資料簡(jiǎn)介 ..................................................................................... 13 功能說明 ................................................................................................................................................ 15 串口電平轉(zhuǎn)換電路 ........................................................................................................................................ 18 MAX232資料簡(jiǎn)介 .................................................................................................................................. 18 RS232(DB9) ......................................................................................................................................... 20 按鍵控制模塊 ............................................................................................................................................. 1 LED 顯示模塊 ............................................................................................................................................. 1 四、軟件設(shè)計(jì)分析 ................................................................................................................................................ 2 軟件系統(tǒng)模塊 ............................................................................................................................................. 2 主模塊 .......................................................................................................................................................... 4 單片機(jī)讀寫 U 盤文件 （ USB 存儲(chǔ) 設(shè)備的文 件級(jí) 接口） ............................................................. 4 本地端的單片機(jī)軟件 ......................................................................................................................... 4 CH375 的 U 盤文件級(jí)子程序庫(kù)說明 ......