ADSP-BF526 EZ-Board Evaluation System Manual
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Using The ADSP-BF526 EZ-Board
SPI Interface
The ADSP-BF526 processor has one serial peripheral interface (SPI) port
with multiple chip select lines. The SPI port connects directly to serial
flash memory, audio codec, and expansion interface II.
Serial flash memory is a 4 Mb SST SST25WF040 device, which is selected
using the
SPISEL1
line of the processor.
SPI flash memory is factory programmed with Das U-Boot—the universal
boot loader. Das U-Boot (
U-Boot
for short) is open source firmware for
embedded processors, including the ADSP-BF526 Blackfin processors.
U-Boot can load files from a variety of peripherals, such as a serial connec-
tion, an Ethernet network connection, or flash memories. U-Boot is
executed at system reset, which automatically loads up another application
(such as the Linux kernel or a stand alone application). U-Boot can parse
many types of files on many types of storage devices.
U-Boot is controlled via a serial communications, the default setting is
56700 baud, 8 data bits, No parity, 1 stop bit. See
for information on the serial connector.
For more information about U-Boot, refer to the online documentation:
http://docs.blackfin.uclinux.org/doku.php?id=bootloaders:u-boot
For U-Boot support on the Blackfin processors, refer to the online help
forums:
http://blackfin.uclinux.org/gf/proj-
ect/u-boot/forum/?action=ForumBrowse&forum_id=51
.
SPI flash can be modified. For instructions, refer to the online help, exam-
ple program included in the EZ-Board installation directory, and U-Boot
documentation. U-Boot includes an SPI flash driver and can be used to
download a new file over Ethernet or serial connection, and write that to
SPI flash.
