Sandisk Memory Stick PRO Duo™ 4GB SDMSPD-4096-E11 Merkblatt
Produktcode
SDMSPD-4096-E11
Symptoms:
Why is the capacity of my flash memory card (as reported by many operating systems)
different than the capacity that is listed on its label?
Why is the capacity of my flash memory card (as reported by many operating systems)
different than the capacity that is listed on its label?
Affects:
Description:
Sandisk products:
CompactFlash
SmartMedia
Multimedia
PC card
Ultra CompactFlash
Memory Stick
Memory Stick Pro
Memory Stick Duo
Extreme CompactFlash
Ultra II CompactFlash
SmartMedia
Multimedia
PC card
Ultra CompactFlash
Memory Stick
Memory Stick Pro
Memory Stick Duo
Extreme CompactFlash
Ultra II CompactFlash
Operating systems:
Most
Hardware platform:
All PCs, Jornadas, etc.
Cause:
The operating system, when reading the size of the card, reports a slightly different capacity than
what is listed on the card’s label
The operating system, when reading the size of the card, reports a slightly different capacity than
what is listed on the card’s label
Solution:
Definitions of a Megabyte:
1) Operating Systems commonly define a Megabyte (MB) as: 2 to the 20th power (1,024KB--
Kilobytes).
2) DiskDrive and Flash Memory Card Manufacturers commonly define a MB as one million bytes
(exactly 1,000,000 bytes).
1) Operating Systems commonly define a Megabyte (MB) as: 2 to the 20th power (1,024KB--
Kilobytes).
2) DiskDrive and Flash Memory Card Manufacturers commonly define a MB as one million bytes
(exactly 1,000,000 bytes).
Unformatted (Capacity)
Also known as drive byte capacity before formatting. The Maximum capacity of disk drive before
formatting equals
[ (# Cylinders) X (# Heads) X (# Sectors) X (# Bytes per Track) ]
Also known as drive byte capacity before formatting. The Maximum capacity of disk drive before
formatting equals
[ (# Cylinders) X (# Heads) X (# Sectors) X (# Bytes per Track) ]
Example:
64MB CompactFlash Card consists of:
490 Cylinders
8 Heads
32 Sectors
512 Bytes per Track
This equates to: [ (490) X (8) X (32) X (512) ] = 64,225,280
64MB CompactFlash Card consists of:
490 Cylinders
8 Heads
32 Sectors
512 Bytes per Track
This equates to: [ (490) X (8) X (32) X (512) ] = 64,225,280
Unformatted Capacity: 64,225,280 bytes
Formatted Capacity: 63,934,464 bytes (User Data)
Formatted Capacity: 63,934,464 bytes (User Data)
Cause:
Disk Drive Companies such as SanDisk define 1 MEGABYTE as 1,000,000 BYTES. Operating
Systems define 1 MEGABYTE as 1,048,576 BYTES (1024K X 1024K or 2 to the 20th power).
Disk Drive Companies such as SanDisk define 1 MEGABYTE as 1,000,000 BYTES. Operating
Systems define 1 MEGABYTE as 1,048,576 BYTES (1024K X 1024K or 2 to the 20th power).
Example:
SanDisk 64MB CompactFlash Card being read by Microsoft Operating System.
SanDisk Total Formatted Capacity divided by 1 MB (as defined by the Operating System)
equates to the following: 63,934,464 BYTES / 1,048,576 BYTES = 60,972,656 BYTES, 60.9MB
displayed by OS.
SanDisk 64MB CompactFlash Card being read by Microsoft Operating System.
SanDisk Total Formatted Capacity divided by 1 MB (as defined by the Operating System)
equates to the following: 63,934,464 BYTES / 1,048,576 BYTES = 60,972,656 BYTES, 60.9MB
displayed by OS.