ADSP-BF537 Blackfin Processor Hardware Reference
6-39
External Bus Interface Unit
t
REF
This is the row refresh period, and typically takes 64 ms.
Dependency: system clock frequency
SDC setting: none
SDC usage:
auto-refresh command
t
REFI
This is the row refresh interval and typically takes 15.6 ms for < 8k rows
and 7.8 ms for >= 8k rows. This spec is available by dividing the number
of rows by t
REF
. This number is used by the SDC refresh counter.
Dependency: system clock frequency
SDC setting: t
REFI
normalized system clock cycles (RDIV register)
SDC usage:
auto-refresh command
SDC Functional Description
The functional description of the SDC is provided in the following
sections.
SDC Operation
The AMC normally generates an external memory address, which then
asserts the corresponding
CS
select, along with
RD
and
WR
strobes. However
these control signals are not used by the SDC. The internal strobes are
used to generate pulsed commands (
SMS
,
SCKE
,
SRAS
,
SCAS
,
SWE
) within a
truth table (see
is based by mapping
ADDR[28:0]
causing an internal memory select to
SDRAM space (see
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 ...