Sdram Controller Commands - Analog Devices ADSP-TS101 TigerSHARC Hardware Reference Manual

SDRAM Controller Commands

SDRAM Controller Commands
This section describes each command the SDRAM controller uses to man-
age the SDRAM interface. These commands are transparent to
applications.
A summary of the various commands used by the on-chip controller for
the SDRAM interface is as follows.
MRS (Mode Register Set). Initializes the SDRAM operation parameters
during the power up sequence.
PRE (Precharge). Precharges the active bank.
ACT (Bank Activate). Activates a page in the required bank.
Read
Write
REF (Refresh). Causes the SDRAM to enter refresh mode and generate all
addresses internally.
SREF (Self-Refresh). Places the SDRAM in self-refresh mode, in which it
controls its refresh operations internally.
NOP (No Operation). Issued after a read or write to enable burst opera-
tion or to insert wait cycles for different SDRAM accesses.
deasserted during this command.
Mode Register Set (MRS) Command
Mode Register Set (
initializes SDRAM operation parameters by using
SDRAM as data input. The
SHARC processor with
SDRAM access after power up.
6-30
) is a part of the system initialization sequence.
MRS
command is issued only by the Tiger-
MRS
= , and must be issued prior to the first
ID 000
ADSP-TS101 TigerSHARC Processor
is
MSSD
of the
ADDR13–0
Hardware Reference
MRS