这个工程主要是简单的显示SD卡的文件目录。
9 q2 z7 M/ m3 n/ O$ s8 A" y" cThis project implements a simple file explorer that displays the directory structure on the SD card.The included CircleOs binary include a SDIO driver and a Fat12/16/32 implementation based on DosFS. This a demo project to show usage of the SD card.
* B; h- I  s6 c( R; O2 RThis project is aimed to be a demo project about how to use the CircleOS filesystem. It can display PRM (converted BMP, JPG, etc) images with a sample viewer.
Included in this project an application to convert BMP, JPG, etc files to PRM with the functionality to scale the image to a desired resolution.
8 c) W5 F! u0 f3 s  m! Z1 ^ Current layout of PRM image file:
 8byte header:
8 q0 [; M7 v" O; R$ R  Q- m) R" \- byte 0: height
- byte 1: width
- 6 bytes for future use
5 g( H/ l: `6 H: P, v- pixel data (2 bytes per pixel)
* E! Y0 `3 A: ~  s# u% [' E FS interface functions:
4 l: _# U/ D/ f8 I6 S1 ?0 A* \u32 FS_Mount(enum STORAGE_device device);
! }) _( }2 p2 }% \u32 FS_Unmount(enum STORAGE_device device);
u32 FS_OpenFile(PVOLINFO volinfo, u8 *path, u8 mode, PFILEINFO fileinfo);
' N8 S* A+ B+ g1 q6 j( Z/ }+ ]u32 FS_ReadFile(PFILEINFO fileinfo,  u8 *buffer, u32 *successcount, u32 len);
u32 FS_WriteFile(PFILEINFO fileinfo,  u8 *buffer, u32 *successcount, u32 len);
, _2 S, J( v& }; h4 C0 d" pu32 FS_Close(PFILEINFO fileinfo);
6 d! U- v3 e6 p3 q. ^2 l4 a' uvoid FS_Seek(PFILEINFO fileinfo, u32 offset);
u32 FS_Delete(PVOLINFO volinfo, u8 *path);
u32 FS_GetNextEntry(PVOLINFO volinfo, PDIRINFO dirinfo, PDIRENT dirent);
u32 FS_OpenDirectory(PVOLINFO volinfo,u8 *dirname, PDIRINFO dirinfo);
- n+ x0 T6 j9 v- u9 I2 m1 m6 ]u32 FS_GetVolumeInfo(u8 unit,  u32 startsector, PVOLINFO volinfo);
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This is a snapshot of my current work in progress with partially integrated jpg decompressor
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