/************************************************************************************************
*
*  U盘文件读写模块 以字节为单位进行U盘文件读写。
*  MCS-51 单片机 汇编示例程序 
*  硬件连接方式: 4线制串口（电源，地，输入，输出） 
*
*************************************************************************************************/

/*--------------------------------
    初始化程序
---------------------------------*/
    ORG 0000H
    AJMP MAIN
    ORG 0100H
/*--------------------------------
主函数
---------------------------------*/
MAIN:
     MOV   SP,  #60H        ;设置堆栈指针
     MOV   TMOD,#20H        ;计数器1工作在方式2
     MOV   TH1, #0F3H        ;晶振频率为24MHz，波特率为9600
     MOV   TL1, #0F3H
        
   ; MOV   TH1,  #0FAH         ;晶振频率为11.0592MHZ,波特率为9600
   ; MOV   TL1,  #0FAH    

     MOV   PCON,#80H        ;smod为1
    SETB  TR1            ;启动计时
     MOV   SCON,#40H

/*---------------------------------------------------------------------
   延时是由于本人所用的 单片机 和USB118A是同一电源供电，
起初上电复位后由于USB118A要进行U盘检测，延时大约让检测完成即可发送指令        
----------------------------------------------------------------------*/
     MOV   R1,#10H        ;闪烁10次
ML:    
    LCALL DELAY        
    LCALL DELAY        ;延时
    LCALL DELAY
    LCALL DELAY
    DJNZ R1,ML

//检测U盘是否连接正常
USB_Detect:    
    CLR    EA            ;关闭中断
    CLR    REN            ;关闭接收位
     MOV     DPTR, #Detect ;检测U盘命令初址
     MOV     R7,  #66        ;R7定义为将要发送的字节数
    LCALL  SEND            ;调用发送子程序
    SETB   REN            ;打开接收位

    JNB    RI,$         ;等待接收到数据
    CLR    RI
     MOV     A,SBUF        ;接收应答码
    CJNE   A,#04H,OUT1    ;04检测应答码，对则继续执行 判断是否成功执行 否则转错误处理
 
    JNB    RI,$         ;等待接收到数据
    CLR    RI
     MOV     A,SBUF        ;接收应答信号
    CJNE   A,#01H,OUT1    ;01判断是否成功执行，成功则继续执行 否则转错误处理


//create file            
    LCALL  CRT
    JNB    RI,$         ;等待接收到数据
    CLR    RI
     MOV     A,SBUF        ;接收应答码
    CJNE   A,#0AH,OUT1    ;0A检测应答码，对则继续执行 判断是否成功执行 否则转错误处理
 
    JNB    RI,$             ;等待接收到数据
    CLR    RI
     MOV     A,SBUF        ;接收应答信号
    CJNE   A,#01H,OUT1    ;01判断是否成功执行，成功则继续执行 否则转错误处理



//open file
    LCALL OP
    JNB    RI,$         ;等待接收到数据
    CLR    RI
     MOV     A,SBUF        ;接收应答码
    CJNE   A,#0DH,OUT1    ;0D检测应答码，对则继续执行 判断是否成功执行 否则转错误处理
 
    JNB    RI,$             ;等待接收到数据
    CLR    RI
     MOV     A,SBUF        ;接收应答信号
    CJNE   A,#01H,OUT1    ;01判断是否成功执行，成功则继续执行 否则转错误处理

//write data
    LCALL  WRT
    SJMP $      
     MOV     IE,#93H
    RET

/*----------------------------------------------
函数功能：当为检测到U盘时，从新发送指令检测
-----------------------------------------------*/
OUT1:                    
     MOV  R7,#66          ;R7定义为将要发送的字节数
    LJMP   USB_Detect ;检测到u盘未成功，重新检测
    RET


/*-----------------------------------------
函数功能：Create file
-------------------------------------------*/
CRT:
       CLR    REN          ;关闭接收位
    LCALL  DELAY
     MOV  R7, #66          ;R7定义为将要发送的字节数
     MOV  DPTR,#Create  ;建立文件命令初址
    LCALL SEND          ;调用发送子程序
    NOP
    NOP
    NOP
    SETB REN          ;打开接收位
    RET


/*----------------------------------------
函数功能：Open file
------------------------------------------*/
OP:
    CLR    REN         ;关闭接收位     
    LCALL  DELAY
     MOV  R7, #66         ;R7定义为将要发送的字节数
     MOV  DPTR,#Open     ;打开文件命令初址
    LCALL SEND         ;调用发送子程序
    NOP
    NOP
    NOP
    SETB REN          ;打开接收位
    RET
    
/*-----------------------------------------
函数功能：Write data
-------------------------------------------*/
WRT:    
    CLR    REN             ;关闭接收位
    LCALL  DELAY
     MOV  R7,#66         ;R7定义为将要发送的字节数
     MOV  DPTR,#Write     ;写文件命令初址    
    LCALL  SEND         ;发送数据

     MOV  R7,#15         ;此处是将要发送的写入数据的字节数
ON:     MOV  DPTR,#Date1     ;数据初地址
    LCALL  SEND         ;发送数据
    NOP
    NOP
    SETB REN        ;打开接收位
    RET

/*----------------------------------------------
函数功能：Re MOV e file
------------------------------------------------*/
REM:    
    CLR   REN             ;关闭接收位
    LCALL DELAY
     MOV  DPTR,#Remove ;设置删除命令初址
    LCALL  SEND         ;发送命令
    NOP
    NOP
    NOP
    SETB REN         ;打开接收位
    RET

/*--------------------------------------------------
函数功能：设置文件指针    
----------------------------------------------------*/    
SFP:    
    CLR REN                     ;关闭接收位
    LCALL DELAY
     MOV  R7,#66
     MOV  DPTR,#SetFilePointer ;设置文件指针命令初址
    LCALL SEND                  ;发送命令
    NOP
    NOP
    NOP
    SETB REN                   ;打开接收位
    RET

/*----------------------------------------------
函数功能：Read file
-----------------------------------------------*/
RAD:
    CLR REN              ;关闭接收位
    LCALL DELAY
     MOV  R7,#66
     MOV  DPTR,#Read      ;设置读命令初址
    LCALL SEND          ;发送命令
    NOP
    NOP
    NOP
    SETB REN          ;打开接收位
    RET
/*--------------------------------------------------
函数功能：Make  dir
---------------------------------------------------*/
MDIR:
    CLR  REN            ;关闭接收位
    LCALL DELAY
     MOV  R7, #66
     MOV  DPTR, #MakeDir    ;设置建立目录初址
    LCALL SEND            ;发送命令
    NOP
    NOP 
    NOP
    SETB REN            ;打开接收位
    RET

/*--------------------------------------------------
函数功能：In dir
---------------------------------------------------*/
IND:
    CLR  REN          ;关闭接收位
    LCALL DELAY
     MOV  R7, #66
     MOV  DPTR, #InDir   ;设置进入目录初址
    LCALL SEND           ;发送命令
    NOP
    NOP 
    NOP
    SETB REN            ;打开接收位
    RET

/*--------------------------------------------------
函数功能：Out dir
---------------------------------------------------*/
OUTD:
    CLR  REN            ;关闭接收位
    LCALL DELAY
     MOV  R7, #66
     MOV  DPTR, #OutDir     ;设置返回目录初址
    LCALL SEND             ;发送命令
    NOP
    NOP 
    NOP
    SETB REN             ;打开接收位
    RET

/*--------------------------------------------------
函数功能：Root dir
---------------------------------------------------*/
ROOTD:
    CLR  REN            ;关闭接收位
    LCALL DELAY
     MOV  R7, #66
     MOV  DPTR, #RootDir    ;设置返回根目录初址
    LCALL SEND            ;发送命令
    NOP
    NOP 
    NOP
    SETB REN            ;打开接收位
    RET

/*-------------------------------------------------
函数功能：Send data
--------------------------------------------------*/
SEND:
     MOV     R0,#00H     ;计数
LOOP:
     MOV     A,R0
     MOV C   A,@A+DPTR ;查表得到要发送的数据
     MOV     SBUF,A     ;发送数据
    JNB    TI,$         ;等待发送完毕
    CLR    TI                
    INC    R0
    DJNZ   R7,LOOP     ;R7发送字节数
    RET
        
/*---------------------------------------------------
函数功能：延时子程序
-----------------------------------------------------*/
DELAY:    
     MOV  R5,#0FFH
LOOP2:
     MOV  R4,#0FFH
LOOP1:
    NOP
    NOP
    DJNZ R4,LOOP1
    DJNZ R5,LOOP2
    RET
                                                                       
/*------------------------------------------------------------------------------------
说明：以下是要发送的命令和数据
-------------------------------------------------------------------------------------*/
Detect:                ;检测u盘命令
    DB 0AAH,0BBH,01H    
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H

Create:                ;建立TEST.TXT文件命令
    DB 0AAH,0BBH,07H    
    DB 54H,45H,53H,54H,20H,20H,20H,20H                        ;Create file name 
    DB 54H,58H,54H                                               ;File type
    DB 20H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 63H,4FH,0FDH,32H                                     ;Create and  revise file time
    DB 00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H 

Open:                ;打开文件命令
    DB 0AAH,0BBH,06H                    
    DB 54H,45H,53H,54H,20H,20H,20H,20H                         ;Open file name
    DB 54H,58H,54H                                             ;File type
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H

Write:                ;写文件命令    
    DB 0AAH,0BBH,09H,00H    
    DB 0FH,00H                                                  ;Write byte number
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H

Read:                ;读文件命令
    DB 0AAH,0BBH,08H
    DB 08H,00H                                                   ;Read file length
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H

Re MOV e:                ;删除文件命令
    DB 0AAH,0BBH,11H,00H
    DB 54H,45H,53H,54H,20H,20H,20H,20H                          ;Delete file name
    DB 54H,58H,54H                                              ;File type
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H

SetFilePointer:            ;设置文件指针命令
    DB 0AAH,0BBH,15H,00H
    DB 148,02H,00H,00H                                           ;设置指针位置
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H
    DB 20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H,20H

MakeDir:            ;建立TEST目录
    DB 0AAH,0BBH,32H
    DB 54H,45H,53H,54H,20H,20H,20H,20H,20H,20H,20H,10H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,0E3H,7EH,0FH,33H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H

InDir:                ;进入TEST目录
    DB 0AAH,0BBH,54H,45H,53H,54H,20H,20H,20H,20H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H

OutDir:                ;返回上一层目录
    DB 0AAH,0BBH,34H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H

RootDir:            ;返回根目录
    DB 0AAH,0BBH,35H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H,00H
    DB 00H,00H

Date1:                ;数据1
    DB 41H,42H,43H,44H,45H,46H,47H,48H,49H,50H,61H,62H,63H,64H,65H
    DB 30H,31H,32H,33H,34H,35H,36H,37H,38H,39H,61H,62H,63H,64H,65H
    DB 30H,31H,32H,33H,34H,35H,36H,37H,38H,39H,61H,62H,63H,64H,65H
    DB 30H,31H,32H,33H,34H,35H,36H,37H,38H,39H,61H,62H,63H,64H,65H
    DB 30H,31H,32H,33H,0DH,0AH
END