ALFAT-OM-337 GHI Electronics, ALFAT-OM-337 Datasheet - Page 49

• Manufacturer Part Number: ALFAT-OM-337
• Description: Memory IC Development Tools ALFAT USB / SD to UART / SPI OEM BOARD
• Manufacturer: GHI Electronics

Specifications of ALFAT-OM-337

• Rohs: yes
• Product: SD OEM Board
• Tool Is For Evaluation Of: SD, SDHC, MMC Cards, USB drives
• Memory Type: Flash
• Operating Supply Voltage: 3.3 V
• Description/function: OEM board offers a seamless way to access files on SD & MMC cards and on USB memory drives
• Interface Type: I2C, SPI, UART, USB
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Part # Aliases: GHI-ALFAT-OM-337

The actual speed of a specific media can be easily determined using the E command,
which range from 1000KBytes/sec to 4000KBytes/sec. This is the internal speed with
complete FAT file system overhead. Such speeds are achieved when using the copy
command. But when using other commands like read or write commands, the serial
connection with the hosting system adds a major delay overhead.
When one of the serial interfaces is used to exchange the data with a hosting system,
some command-response overhead is introduced. There is also a maximum clock and
other restrictions on the interfaces. On an average, file access speed is about
230KBytes/sec when using UART or SPI and about 25KBytes/sec when using I2C. That is
about the same when using SD, USB FS or USB HS.
To achieve higher writing speed, ALFAT command-set includes
File
Command but, with L Command, it uses internal DMA to reach faster receiving rates. The
average speed with this command is 1400KBytes/sec with SD cards, 1200KBytes/sec with
USB HS and 750KBytes/sec with USB FS.
9.3. Serial Interface Speed Overhead
GHI Electronics
Rev. 1.13
command). Available for SPI interface only, this command is very similar to the W
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Conditions of Use and Performance
L Command (Fast Write to
ALFAT SoC Processor
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