
. . . . .
M E M O R Y C O N T R O L L E R
Dynamic Memory Active Bank A to Active Bank B Time register
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245
Register
Register bit
assignment
D y n a m i c M e m o r y A c t i v e B a n k A t o A c t i v e B a n k B T i m e
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
r e g i s t e r
Address: A070 0054
The Dynamic Memory Active Bank A to Active Bank B Time register allows you to
program the active bank A to active bank B latency, t
RRD
. It is recommended that
this register be modified during system initialization, or when there are no current
or outstanding transactions. Wait until the memory controller is idle, then enter
low-power or disabled mode. This value normally is found in SDRAM datasheets as
t
RRD
.
Note:
The Dynamic Memory Active Bank A to Active Bank B Time register is used for
all four dynamic memory chip selects. The worst case value for all chip
selects must be programmed.
Register
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
Reserved
Reserved
XSR
Bits
Access
Mnemonic
Description
D31:05
N/A
Reserved
N/A (do not modify)
D04:00
R/W
XSR
Exit self-refresh to active time command
0x0–0x1E
n+1 clock cycles, where the delay is in
clk_out
cycles
0
x1F
32 clock cycles (reset value on
reset_n
)
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
Reserved
Reserved
RRD
Summary of Contents for NS9215
Page 1: ...NS9215 Hardware Reference 90000847_C Release date 10 April 2008...
Page 3: ......
Page 4: ......
Page 26: ...26 Hardware Reference NS9215...
Page 44: ...P I N O U T 26 5 System clock 44 Hardware Reference NS9215 System clock drawing...
Page 52: ...P I N O U T 26 5 Power and ground 52 Hardware Reference NS9215...
Page 80: ...I O C O N T ROL M O D U L E Memory Bus Configuration register 80 Hardware Reference NS9215...
Page 136: ...WOR KI N G W I TH T H E C P U Noncachable instruction fetches 136 Hardware Reference NS9215...
Page 202: ...S Y S T E M C O N T RO L M OD U L E RTC Module Control register 202 Hardware Reference NS9215...
Page 354: ...E X T E R N A L D M A DMA Peripheral Chip Select register 354 Hardware Reference NS9215...
Page 472: ...R E A L TI M E C L O C K M O D U L E General Status register 472 Hardware Reference NS9215...
Page 512: ...TI M I NG Clock timing 512 Hardware Reference NS9215...
Page 515: ...PA CKA GING Processor Dimensions www digiembedded com 515...
Page 516: ...PA CKA GING Processor Dimensions 516 Hardware Reference NS9215...