
. . . . .
M E M O R Y C O N T R O L L E R
Static Memory Extended Wait register
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247
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S t a t i c M e m o r y E x t e n d e d W a i t r e g i s t e r
Address: A070 0080
The Static Memory Extended Wait register times long static memory read and write
transfers (which are longer than can be supported by the Static Memory Read Delay
registers or the Static Memory Write Delay registers) when the EW (extended wait)
bit in the related Static Memory Configuration register is enabled.
There is only one Static Memory Extended Wait register, which is used by the
relevant static memory chip select if the appropriate EW bit is set in the Static
Memory Configuration register.
It is recommended that this register be modified during system initialization, or
when there are no current or outstanding transactions. If necessary, however, these
control bits can be changed during normal operation.
Register
Register bit
assignment
Example
Static memory read/write time = 16
μ
s
CLK frequency = 50 MHz
This value must be programmed into the Static Memory Extended Wait register:
(16 x 10
-6
x 50 x 10
6
/ 16) - 1 = 49
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D y n a m i c M e m o r y C o n f i g u r a t i o n 0 – 3 r e g i s t e r s
Address: A070 0100 / 0120 / 0140 / 0160
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
EXTW
Bits
Access
Mnemonic
Description
D31:10
N/A
Reserved
N/A (do not modify)
D09:00
R/W
EXTW
External wait timeout
0x0
16 clock cycles, where the delay is in
clk_out
cycles
0
x1-
0
x3FF
(n=1) x 16 clock cycles
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...