SDRAM Interface Functional Overview
Memory Connection
Copyright © 2002 Marvell
CONFIDENTIAL
Doc. No. MV-S300165-00, Rev. A
May 21, 2002, Preliminary
Document Classification: Proprietary Information
Page 35
Note
The DRAM controller drives the DRAM address and control pins to their inactive value during reset
assertion, as required by the DRAM specification (100 us of idle cycles before DRAM initialization).
4.2
Memory Connection
The GT-64260A supports 16, 64, 128, 256 and 512 MB SDRAM devices. Each SDRAM physical bank (SCS[3:0])
can be built from different SDRAM devices. The DRAM density is configured via the DRAM Bank Parameter regis-
ters.
for details on how the various DRAM device sizes differ in the usage of DAdr[12:0] and BankSel[1:0]
lines.
SData[63:0]
t/s I/O
When using DRAM DIMMs,
connect to the data pins.
When using SDRAM
devices, must be connected
to data pins of each device in
parallel to achieve 64-bits
data width.
In UMA mode the
master must drive
these pins.
SDRAM Data
ECC[7:0]
t/s I/O
When using DRAM DIMMs,
connect to the DP pin. When
using SDRAM devices, must
be connected to ECC bank
device.
NOTE:
Since the SDRAM
controllers do not write par-
tials when ECC is enabled,
the ECC bank device can be
connected to any of the
SDQM pins.
In UMA mode the
master must drive
these pins.
SDRAM ECC
Table 8:
SDRAM Interface Pinout Description
SDRAM
Addressing
x4
x8
x16
x32
16 Mb
(2 virtual banks)
Row
A0 - A10
A0 - A10
NA
NA
Column
A0 - A9
A0 - A8
NA
NA
64 Mb
(4 virtual banks)
Row
A0 - A11
A0 - A11
A0 - A11
A0 - A10
Column
A0 - A9
A0 - A8
A0 - A7
A0 - A7
Table 7:
SDRAM Interface Pinout Description (Continued)
Pin Name
Input/
Output
SDRAM Device or
DIMM Connector
Required
External
Resistor
Description