Digi NS9750 User Manual

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M e m o r y C o n t r o l l e r

Dynamic Memory Exit Self-refresh register

Address: A070 0050
The Dynamic memory Exit Self-refresh register allows you to program the exit self-
refresh to active command time, t

XSR

. 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

XSR

Note:

The Dynamic Memory Exit Self-refresh register is used for all four dynamic
memory chip selects. The worst case value for all the chip selects must be
programmed.

Register bit assignment

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

cycles.

0x1F

32 clock cycles (reset value on

reset_n

)

Table 152: Dynamic Memory Exit Self-refresh register

Reserved

XSR