SDFS 1.47 KB
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SDFS SPECIFICATION

SDFS is a filing system that provides access to MMC or SD memory card reader
slots attached directly to the system. For the avoidance of doubt, this excludes
any such card readers which are attached via a USB interface: these feature an
intermediate controller which makes the memory card appear like a generic
USB memory device, and does not permit direct access to the MMC/SD command set.

SDFS is a FileCore filing system, so in many ways it acts like ADFS, SCSIFS or
RAMFS.

SWI SDFS_DiscOp (SWI &59040)
SWI SDFS_Drives (SWI &59042)
SWI SDFS_FreeSpace (SWI &59043)
SWI SDFS_DescribeDisc (SWI &59045)
SWI SDFS_MiscOp (SWI &59049)
SWI SDFS_SectorDiscOp (SWI &5904A)
SWI SDFS_FreeSpace64 (SWI &5904B)
SWI SDFS_DiscOp64 (SWI &5904C)

These SWIs are all identical to the equivalent FileCore ones, except that the
caller does not need to set up R8 on entry.


SWI SDFS_ReadCardInfo (SWI &59060)

On entry

R0 = reason code:
       0 => return card capacity in bytes in R2-R3 (64-bit little-endian)
31
       1 => return card location (slot, bus, RCA) in R2
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       other values reserved for future use
R1 = drive number

On exit

Some registers may be used to return results, depending upon the reason code in
R0. Other registers are preserved.

Not reentrant


*SDFS

Selects SDFS as the current filing system. This command takes no parameters.


*Configure SDFSdrive

Sets the drive number that SDFS defaults to when it starts (e.g. during boot)

Syntax: *Configure SDFSdrive <drive>