ADSP-BF535 Blackfin Processor Hardware Reference
18-71
External Bus Interface Unit
register (
EBIU_SDGCTL
) must be written, and a transfer must be started to
SDRAM address space. The
SDRS
bit of the SDRAM Control Status regis-
ter can be checked to determine the current state of the SDC. If this bit is
set, the SDRAM power-up sequence has not been initiated.
The
RDIV
field of the
EBIU_SDRRC
register should be written to set the
SDRAM refresh rate.
The
EBIU_SDBCTL
register should be written to describe the sizes and
SDRAM memory configuration used (
EBxSZ
and
EBxCAW
) and to enable
the external banks which are populated (
EBxE
). Note until the SDRAM
power-up sequence has been started, any access to SDRAM address space,
regardless of the state of the
EBxE
bits, generates an internal bus error, and
the access does not occur externally.
For more information, see “Error
Detection” on page 18-8.
After the SDRAM power-up sequence has com-
pleted, any transfer to a disabled external bank results in a hardware error
interrupt, and the SDRAM transfer does not occur.
The
EBIU_SDGCTL
register should be written:
• to set the SDRAM cycle timing options (
CL
,
TRAS
,
TRP
,
TRCD
,
TWR
,
EBUFE
)
• to enable the SDRAM clocks (
SCTLE
,
SCLK1
)
• to set the prefetch functionality (
PFE
,
PFP
)
• to set the datapath width (
X16DE
)
• to select and enable the start of the SDRAM power-up sequence
(
PSM
,
PSSE
)
Note if
SCTLE
is disabled, any access to SDRAM address space generates an
internal bus error and the access does not occur externally.
For more infor-
mation, see “Error Detection” on page 18-8.
Содержание ADSP-BF535 Blackfin
Страница 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Страница 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 908: ...SDRAM Controller External Bus Interface Unit B 36 ADSP BF535 Blackfin Processor Hardware Reference...