SDC Description of Operation
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ADSP-BF537 Blackfin Processor Hardware Reference
Burst Type
The burst type determines the address order in which the SDRAM deliv-
ers burst data. The burst type is selected by writing the
BT
bits in the
SDRAM’s mode register during the SDRAM powerup sequence.
CAS Latency
The CAS latency or read latency specifies the time between latching a read
address and driving the data off chip. This spec is normalized to the sys-
tem clock and varies from 2 to 3 cycles based on the speed. The CAS
latency is selected by writing the
CL
bits in the SDRAM’s mode register
during the SDRAM powerup sequence.
Data I/O Mask Function
SDRAMs allow a data byte-masking capability on writes. The mask pins
DQM[1:0]
are used to block the data input buffer of the SDRAM during
write operations.
SDRAM Commands
SDRAM commands are not based on typical read or write strobes. The
pulsed
CS
,
RAS
,
CAS
, and
WE
lines determine the command on the rising
clock edge by a truth table.
Mode Register Set (MRS) command
SDRAM devices contain an internal extended configuration register
which allows specification of the mobile SDRAM device’s functionality.
Extended Mode Register Set (EMRS) command
Mobile SDRAM devices contain an internal extended configuration regis-
ter which allows specification of the mobile SDRAM device’s
functionality.
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...