这几天在看原子哥的汉字显示实验-遇到几个问题。

xiaolong12

ftinfo.gbk12size=fftemp->fsize;      //GBK12字库大小
flashaddr=ftinfo.f12addr;              //GBK12的起始地址
ftinfo.gkb16size=fftemp->fsize;      //GBK16字库大小

SD卡更新程序时--那几个结构体参数fftemp->fsize在哪被赋值的呢？实在没看出来----

exv

[mw_shl_code=c,true] res=f_read(fftemp,tempbuf,4096,(UINT *)&bread); //读取数据[/mw_shl_code]

xiaolong12

回复【2楼】exv:
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4096固定的？

exv

[mw_shl_code=c,true]/* File object structure (FIL) */ typedef struct { FATFS* fs; /* Pointer to the related file system object (**do not change order**) */ WORD id; /* Owner file system mount ID (**do not change order**) */ BYTE flag; /* File status flags */ BYTE err; /* Abort flag (error code) */ DWORD fptr; /* File read/write pointer (Zeroed on file open) */ DWORD fsize; /* File size */ DWORD sclust; /* File data start cluster (0:no data cluster, always 0 when fsize is 0) */ DWORD clust; /* Current cluster of fpter */ DWORD dsect; /* Current data sector of fpter */ #if !_FS_READONLY DWORD dir_sect; /* Sector containing the directory entry */ BYTE* dir_ptr; /* Pointer to the directory entry in the window */ #endif #if _USE_FASTSEEK DWORD* cltbl; /* Pointer to the cluster link map table (Nulled on file open) */ #endif #if _FS_LOCK UINT lockid; /* File lock ID (index of file semaphore table Files[]) */ #endif #if !_FS_TINY BYTE buf[_MAX_SS]; /* File data read/write buffer */ #endif } FIL;[/mw_shl_code]

最后要的是FIL* fp指向的内容（包含fsize等），4096应该是一个足够大的空间，以容下这个结构体可能的大小。

 

[mw_shl_code=c,true]FRESULT f_read ( FIL* fp, /* Pointer to the file object */ void* buff, /* Pointer to data buffer */ UINT btr, /* Number of bytes to read */ UINT* br /* Pointer to number of bytes read */ )[/mw_shl_code]

xiaolong12

回复【4楼】exv:
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fftemp是怎么被赋值的呢？  它是定义的一个FIL结构体类型的变量，怎么给fsize赋值的？  难道是结构体赋值？

exv

回复【5楼】xiaolong12:
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通过f_read得到整个FIL结构体内容，里面已包含了fsize。