83Plus:Software:usb8x/Asm Interface/MSD/UFI Read

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Synopsis

Name: UFI_Read

Minimum usb8x version: 0.10

Reads one sector from (MSDLBA) address and stores in sector buffer.

Inputs

  • DE contains area to store sector
  • (MSDLBA) contains LBA address of sector to read

Outputs

  • DE points to contents of (MBDLBA) sector
  • C set if problems

Destroys

  • AF, BC, DE, HL

Notes

(MSDLBA) is a 4-byte area in the mass storage driver's internal memory buffer used by this routine. The following example code would set the value to zero, where appBackUpScreen is where the mass storage internal buffer is: 

xor a
ld (appBackUpScreen+MSDLBA),a
ld (appBackUpScreen+MSDLBA+1),a
ld (appBackUpScreen+MSDLBA+2),a
ld (appBackUpScreen+MSDLBA+3),a

This is just to demonstrate where MSDLBA is in memory. See [[../MSD_Initialize|MSD_Initialize]] for more information about the internal buffer used by the mass storage driver.

See Also

  • [[../MSD_Initialize|MSD_Initialize]] - Initializes the mass storage driver
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