GMS30C7201 Datasheet, PDF (83/352 Pages) Hynix Semiconductor – 60MHz operation frequency Low power consumption

SDRAM Controller
8.6 SDRAM Memory Map
The SDRAM controller can interface with up to four SDRAMs. Three SDRAM sizes are
supported—16, 64 and 128Mbits—which may be organized in either two or four banks but
which must have a 16-bit data bus. A maximum of 64Mbytes of memory may be addressed by
the SDRAM controller, which is subdivided into four 16Mbyte blocks, one for each of the
external SDRAMs.
The mapping of the AMBA address bus to the SDRAM row and column addresses is given in
Table 8-8: SDRAM row/column address map. The first row of the diagram indicates the
SDRAM address bit (A[13:0]); the remaining numbers indicate the AMBA address bits
MBA[23:1]. Note that for 16Mbit devices, pins A[11,9] on the SDRAM should be connected to
pins A[13,12] on the GMS30C7201, and the pins A[11,9] should not be connected.
SDRAM
13
12
11
10
ADDR
(BS0) (BS1)
Row 16Mbit 10*
9*
Device
Note 20*
1
Col 16Mbit 10
9
Device
Note 20
1
Row 64Mbit 10*
9*
Device
22* 20*
Col 64Mbit 10
9
Device
22
20
Row
128Mbit
Device
10*
9*
22* 20*
Col
128Mbit
Device
10
9
22
20
Mode Write 10*
9*
22* 20*
Summary
10
9
22
20
9
8
7
6
5
4
3
2
1
0
Note 19* 18* 17* 16* 15* 14* 13* 12* 11*
1
Note 23
8*
7*
6*
5*
4*
3*
2*
Note
1
2
21* 19* 18* 17* 16* 15* 14* 13* 12* 11*
21
23
8*
7*
6*
5*
4*
3*
2*
Note
2
21* 19* 18* 17* 16* 15* 14* 13* 12* 11*
21
23* 8*
7*
6*
5*
4*
3*
2*
Note
2
21* 19* 18* 17* 16* 15* 14* 13* 12* Note
2
21
19/23 18/8 17/7 16/6 15/5 14/4 13/3 12/2 11
Table 8-8: SDRAM row/column address map
Notes
(1) For the 16Mbit device, SDRAM address line A11 should be connected to the GMS30C7201
pin SA[13](BS0), and the SDRAM address line A9 should be connected to the GMS30C7201 pin
SA[12](BS1). The GMS30C7201 address lines A11 and A9 should not be connected.
(2) Since all burst accesses commence on a word boundary, and SDRAM addresses are non-
incrementing (the address incrementer is internal to the device), column address zero will
always be driven to logic ‘0’.
* An asterisk denotes the address lines that are used by the SDRAM.
The start addresses of each SDRAM is fixed to a 16Mbyte boundary. The memory management
unit will be used to map the actual banks that exist into contiguous memory as seen by the ARM.
Bits [25:24] of the AMBA address bus select the device to be initialized, as described in
Table 8-9: SDRAM device selection on page 8-12.
GMS30C7201 Data Sheet
8-11