Analog Devices SHARC ADSP-214 Series Hardware Reference Manual page 203

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T0
T1
DDR2_CLKx
DDR2_CLKx/
COMMAND
READ
ACT
BA0, BA1,
Bank
Bank
BA2
a
a
t RDD(min)
Figure 3-17. Bank Activation for a 8 Banked Device
Multibank access reduces precharge and activation cycles by map-
ping opcode/data among different internal DDR2 banks driven by
the (
DDR2_BA2-0
Multi Bank Operation with Data Packing
A logical address correspond to 2 physical addresses. Consequently a phys-
ical address for example of 1024 x 16 page size translates into a logical
address of 512 x 16 words to satisfy the packing. According to this all row
addresses are shifted by 2.
A populated DDR2 of 8M x 16 x 8 with 1K words page size connected to
external bank 0 has a logical mapping as follows.
Page Interleaving (DDR2ADDRMODE bit = 0):
0x200000 logical start address int bankA
0x2001FF logical end address int bankA
0x200200 logical start address int bankB
0x2003FF logical end address int bankB
0x200400 logical start address int bankC
0x2005FF logical end address int bankC
0x200600 logical start address int bankD
0x2007FF logical end address int bankD
0x200800 logical start address int bankE
0x2009FF logical end address int bankE
ADSP-214xx SHARC Processor Hardware Reference
www.BDTIC.com/ADI
T2
T3
T4
READ
ACT
ACT
Bank
Bank
Bank
b
b
c
t RDD(min)
) pins and external memory selects (
T5
T6
T7
READ
READ
ACT
Bank
Bank
Bank
c
d
d
t RDD(min)
t RDD(min)
t
External Port
T8
T9
T10
NOP
NOP
NOP
).
DDR2_CS3-0
3-73
T11
ACT
Bank
e

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