比如下面的: EXTRN CODE (CH375Reset) ; 復(fù)位CH375 */ EXTRN CODE (CH375Init) ; 初始化CH375 */ EXTRN CODE (CH375DiskConnect) ; 檢查磁盤是否連接 */ EXTRN CODE (CH375DiskReady) ; 查詢磁盤是否準備好 */ 因為我用的單片機是89c52很小的程序空間,同時我使用的功能目前只需要從U盤里面讀比如512字節(jié)就可以了,我用的ch375hft.asm+ch375hf6.inc+ch375hf6.lib 就超出了程序空間,同時編譯的時候提示

COPYRIGHT KEIL ELEKTRONIK GmbH 1987 - 2002 ASSEMBLY COMPLETE. 0 WARNING(S), 0 ERROR(S) MedWin V2.39 Linking...... BL51 BANKED LINKER/LOCATER V5.00 - SN: K1PRP-MWVI9E COPYRIGHT KEIL ELEKTRONIK GmbH 1987 - 2002 CH375HFT.obj,D:\工作\CH375B\CH375HF4.LIB TO usb375.Omf RAMSIZE(256) *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375GETVER?CH375MAI *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375INIT?CH375MAI *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375FILECLOSE?CH375MAI *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375FILECREATE?CH375MAI *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375FILEMODIFY?CH375MAI *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375DISKREADY?CH375MAI *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375FILELOCATE?CH375SEC *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375FILEREADX?CH375SEC *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375FILEWRITEX?CH375SEC *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375BYTELOCATE?CH375BYT *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375BYTEREAD?CH375BYT *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375BYTEWRITE?CH375BYT *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375DISKSIZE?CH375DSZ *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375DISKQUERY?CH375DSZ *** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS SEGMENT: ?PR?CH375SDISKREADY?CH375SRD *** WARNING L10: CANNOT DETERMINE ROOT SEGMENT Program Size: data=92.4 xdata=27165 code=10898 LINK/LOCATE RUN COMPLETE. 16 WARNING(S), 0 ERROR(S) Write Intel HEX format file "D:\Manley\PMedWin\usb375.hex" successfully. Initial Emulator...seccessfully. Loading program "usb375.Omf"... ............................................................ ........... ************* T o t a l ************* Code number: 10898 bytes. Minimal address: 0000H. Maximal address: 2A91H. ************************************* Loading program Completed.

另外 內(nèi)置固件模式是怎么會事呢?好象這是最簡單的模式了,看了資料還是不知道怎么做...

（1）庫里面的程序肯定是不會提供的，除程序空間，89c52的RAM也不夠，如果你只想讀文件的話，用CH375HF3試試，只是只讀版本庫，空間小一些 （2）這些警告是指部分庫程序未調(diào)用 （3）內(nèi)置固件模式？是指設(shè)備么，這個模式下，只要成功設(shè)置模式后，CH375會自動完成設(shè)備枚舉，不需要外部單片機控制

內(nèi)置固件是指CH375里面里面的固件,在設(shè)備方式下,375里面有一些相關(guān)描述符,控制傳輸?shù)纫恍┑自腢SB協(xié)議由375自己處理 MCU推薦使用16KROM的.RAM大于600多個字節(jié).

好吧,.我就用ch375hf3試試,另外,我的系統(tǒng)是這樣的: 采用總線方式,但是又不能用DPTR,只能用movx @r0(因為p2要用作其他用),這樣的話,還可以直接套用嗎?我估計你們的庫用的是DPTR,貌似還是不行,難道又要增加硬件...或者我只能不用總線方式,只有換直接I/O模擬操作,那樣,又用什么現(xiàn)成的程序呢? d0-d7接p0口,/int接p3.2 a0 用74hc573譯碼 /cs直接I/O口控制,/RD,/WR接51的/RD,/WR,讀寫指令我用的movx @r0(因為p2要用作其他用)

（1）如果在總線操作時，P2口是空閑的，那么是可以套用的，反之則不行 （2）ch375hf3內(nèi)部是總線接口，沒法改用模擬I/O

如果按照你所說的，那么你只好采用模擬I/O口方式，但是相對于總線方式來說速度會慢一些。至于例程你可以去參考CH375LIB\MCS51\FILELIBC\EXAM7