ADSP-BF537 Blackfin Processor Hardware Reference
6-67
External Bus Interface Unit
EBIU_SDGCTL Register
The SDRAM memory global control register (
EBIU_SDGCTL
) includes all
programmable parameters associated with the SDRAM access timing and
configuration.
shows the
EBIU_SDGCTL
register bit definitions.
•
SDRAM clock enable
(
SCTLE
)
The
SCTLE
bit is used to enable or disable the SDC. If
SCTLE
is dis-
abled, any access to SDRAM address space generates an internal
bus error, and the access does not occur externally. For more infor-
mation, see
SCTLE
is
disabled, all SDC control pins are in their inactive states and the
SDRAM clock is not running. The
SCTLE
bit must be enabled for
SDC operation and is enabled by default at reset. The CAS latency
(
CL
), SDRAM t
RAS
timing (
TRAS
), SDRAM t
RP
timing (
TRP
),
SDRAM t
RCD
timing (
TRCD
), and SDRAM t
WR
timing (
TWR
) bits
should be programmed based on the system clock frequency and
the timing specifications of the SDRAM used.
The
SCTLE
bit allows software to disable all SDRAM control pins.
These pins are
SDQM[3:0]
,
SCAS
,
SRAS
,
SWE
,
SCKE
, and
CLKOUT
.
•
SCTLE
= 0
Disable all SDRAM control pins (control pins negated,
CLKOUT
low).
•
SCTLE
= 1
Enable all SDRAM control pins (
CLKOUT
toggles).
Note the
CLKOUT
function is also shared with the AMC. Even if
SCTLE
is disabled,
CLKOUT
can be enabled independently by the
CLKOUT
enable in the AMC (
AMCKEN
in the
EBIU_AMGCTL
register).
If the system does not use SDRAM,
SCTLE
should be set to 0.
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 ...