DDR2 DRAM Controller (ADSP-2146x)
3-62
ADSP-214xx SHARC Processor Hardware Reference
bits in the
DDR2CTL0
register. The bank address width is three bits as
.
Row Address Width (DDR2RAW).
These bits in the
DDRCTL0
register
determine the row width of the DDR. The
DDR2RAW
bits can be pro-
grammed for row widths of 8 to 15.
Column Address Width (DDR2CAW).
The DDR2 memory control reg-
ister also includes external bank specific programmable parameters. The
external bank can be configured for a different DDR2 size. The DDR
controller determines the internal DDR2 page size from the
X16DE
and
DDR2CAW
parameters. Page sizes of 256, 512, 1K, 2K and 4K words are
supported.
The mapping of the addresses depends on the row address width
(
DDR2RAW
), column address width (
DDR2CAW
), and the address mode
bit (
DDR2ADDRMODE
) setting.
16-Bit Address Mapping
Even if the external data width is 16 bits, the processor supports only
32-bit data accesses. The DDR2 controller performs two 16-bit accesses to
get and place 32-bit data. The controller takes the IA address and appends
one extra bit to the LSB to generate the address externally.
Table 3-11. External Memory Address Bank Decoding
IA[27]
IA[26]
External Bank
0
0
Bank 0
0
1
Bank 1
1
0
Bank 2
1
1
Bank 3
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Содержание SHARC ADSP-214 Series
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Страница 72: ...Notation Conventions lxxii ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 130: ...Programming Model 2 52 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 264: ...Programming Models 3 134 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 290: ...Programming Model 4 26 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 296: ...Programming Model 5 6 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 396: ...Effect Latency 7 28 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 520: ...Programming Model 10 62 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 616: ...Debug Features 14 22 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 656: ...Programming Model 15 40 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 714: ...Programming Model 19 10 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 1132: ...Register Listing A 306 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 1192: ...Index I 34 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...