Datasheet

Mmc_Fat_Get_Swap_File
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MIKROELEKTRONIKA - SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD
Libraries
mikroC PRO for AVR
CHAPTER 6
Prototype
unsigned long Mmc_Fat_Get_Swap_File(unsigned long sectors_cnt,
char* filename, char file_attr);
Returns
- Number of the start sector for the newly created swap file, if there was
enough free space on the MMC/SD card to create file of required size.
- 0 - otherwise.
Description
This function is used to create a swap file of predefined name and size on the
MMC/SD media. If a file with specified name already exists on the media,
search for consecutive sectors will ignore sectors occupied by this file. There-
fore, it is recomended to erase such file if it exists before calling this function. If
it is not erased and there is still enough space for new swap file, this function
will delete it after allocating new memory space for new swap file.
The purpose of the swap file is to make reading and writing to MMC/SD media
as fast as possible, by using the Mmc_Read_Sector() and Mmc_Write_Sector()
functions directly, without potentially damaging the FAT system. Swap file can be
considered as a "window" on the media where user can freely write/read the
data. It's main purpose in mikroC's library is to be used for fast data acquisition;
when the time-critical acquisition has finished, the data can be re-written into a
"normal" file, and formatted in the most suitable way.
Parameters:
-
sectors_cnt: number of consecutive sectors that user wants the
swap file to have.
- filename: name of the file that should be assigned for file operations.
File name should be in DOS 8.3 (file_name.extension) format. The file
name and extension will be automatically padded with spaces by the
library if they have less than length required (i.e. "mikro.tx" ->
"mikro .tx "), so the user does no have to take care of that. The file
name and extension are case insensitive. The library will convert them
to proper case automatically, so the user does not have to take care of
that. Also, in order to keep backward compatibility with first version of
this library, file names can be entered as UPPERCASE string of 11
bytes in length with no dot character between file name and extension
(i.e. "MIKROELETXT" -> MIKROELE.TXT). In this case last 3 charac
ters of the string are considered to be file extension.
-
file_attr: file creation and attributs flags. Each bit corresponds to
appropriate file attribut: