USB.rar_5409_usb dsp_单片机通信

mCH375_DISK_READ 函数的代码如下：

/* 从U 盘读取多个扇区的数据块到缓冲区 */

unsigned int mCH375_DISK_READ ( unsigned long iLbaStart, unsigned int

iSectorCount, unsigned int *iBuffer )

{

/* iLbaStart 是准备读取的线性起始扇区号, iSectorCount 是准备读取的扇区数, iBuffer

是存放返回数据的缓冲区的起址 */

unsigned int i;

if (mWaitReady( ) == FALSE)

i = (unsigned int)( iLbaStart >> 8 );

CH375_WR_DAT_PORT( i );

i = (unsigned int)( iLbaStart >> 16 );

CH375_WR_DAT_PORT ( i );

i = (unsigned int) ( iLbaStart >> 24 );

CH375_WR_DAT_PORT( i ); /* LBA的最高8 位 */

CH375_WR_DAT_PORT( iSectorCount ); /* 扇区数 */

return ( mWaitReady( ) );}