Dynamic memory precharge command period register, Register register bit assignment – Digi NS9215 User Manual
Page 238

M E M O R Y C O N T R O L L E R
Dynamic Memory Precharge Command Period register
238
Hardware Reference NS9215
Register
Register bit
assignment
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D y n a m i c M e m o r y P r e c h a r g e C o m m a n d P e r i o d r e g i s t e r
Address: A070 0030
The Dynamic Memory Precharge Command Period register allows you to program the
precharge command period, t
RP
. Modify this register only during system
initialization. This value normally is found in SDRAM datasheets as t
RP
.
Note:
The Dynamic Memory Precharge Command Period 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
RD
Bits
Access
Mnemonic
Description
D31:02
N/A
Reserved
N/A (do not modify)
D01:00
R/W
RD
Read data strategy
00
Reserved.
01
Command delayed strategy, using
CLKDELAY
(command
delayed, clock out not delayed).
10
Command delayed strategy plus one clock cycle, using
CLKDELAY
(command delayed, clock out not delayed).
11
Command delayed strategy plus two clock cycles, using
CLKDELAY
(command delayed, clock out not delayed).
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
RP