Description of Operation
21-8
ADSP-BF50x Blackfin Processor Hardware Reference
• Identify the device type,
• Assign/request a relative card address (RCA)
Only once a device has been assigned an RCA will the device then transi-
tion to a stand-by state, where it is then known to be in
data transfer mode
.
Only once the device has entered this mode may data transfers then take
place. All communication during the card identification phase between
the host and the attached device occur via the
RSI_CMD
signal. The maxi-
mum clock frequencies during this identification phase may typically be
far lower than the cards maximum operating frequency for data transfers.
Once the device is in data transfer mode, communication may take place
via the
RSI_CMD
and the
RSI_DATAx
signals. The card may be interrogated
to then identify further supported features such as supported bus widths,
maximum supported clock frequency, and the device capacity. At this
point the bus width may then be altered and the supplied clock frequency
increased.
Data may be written to the device or read from the device using the
following two methods:
• Stream reads and writes
• Block reads and writes
Stream transfers result in a continual stream of data being transferred until
a specific command is sent to the device by the RSI informing the device
to stop the transfer. There may be additional maximum operating fre-
quency limitations imposed by the device for stream read and write
operations. In addition, stream write operations may have restrictions that
are dependent on writable block boundaries.
Block-based transfers result in a block of a pre-configured size being trans-
ferred. The size of a block is dependent upon the device and can be
obtained by reading registers contained on the device that are read during
the device detection procedure.
Summary of Contents for EZ-KIT Lite ADSP-BF506F
Page 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Page 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...