Digi NS9750 User Manual
Page 252
R e g i s t e r s
2 2 8
N S 9 7 5 0 H a r d w a r e R e f e r e n c e
A chip select can be connected to a single memory device; in this situation, the chip
select data bus width is the same as the device width. As an alternative, the chip
select can be connected to a number of external devices. In this situation, the chip
select data bus width is the sum of the memory device databus widths.
Examples
1
0
100
00
512 Mb (64Mx8), 4 banks, row length=13, column length=11
1
0
100
01
512 Mb (32Mx16), 4 banks, row length=13, column length=10
32-bit extended bus low-power SDRAM address mapping (bank, row, column)
1
1
000
00
16 Mb (2Mx8), 2 banks, row length=11, column length=9
1
1
000
01
16 Mb (1Mx16), 2 banks, row length=11, column length=8
1
1
001
00
64 Mb (8Mx8), 4 banks, row length=12, column length=9
1
1
001
01
64 MB (4Mx16), 4 banks, row length=12, column length=8
1
1
001
10
64 Mb (2Mx32), 4 banks, row length=11, column length=8
1
1
010
00
128 Mb (16Mx8), 4 banks, row length=12, column length=10
1
1
010
01
128 Mb (8Mx16), 4 banks, row length=12, column length=9
1
1
010
10
128 Mb (4Mx32), 4 banks, row length=12, column length=8
1
1
011
00
256 Mb (32Mx8), 4 banks, row length=13, column length=10
1
1
011
01
256 Mb (16Mx16), 4 banks, row length=13, column length=9
1
1
011 10
256 Mb (8Mx32), 4 banks, row length=13, column length=8
1
1
100
00
512 Mb (64Mx8), 4 banks, row length=13, column length=11
1
1
100
01
512 Mb (32Mx16), 4 banks, row length=13, column length=10
For a chip select connected to
Select this mapping
32-bit wide memory device
32-bit wide address mapping
16-bit wide memory device
16-bit wide address mapping
4 x 8-bit wide memory devices
32-bit wide address mapping
2 x 8-bit memory devices
16-bit wide address mapping
[14]
[12]
[11:9]
[8:7]
Description
Table 157: Address mapping