For example, to write H'0230 to the area 2 SDMR register, arbitrary data is written to address
H'FF900000 (address “Y”) + H'08C0 (value “X”) (= H'FF9008C0). As a result, H'0230 is written
to the SDMR register. The range of value “X” is H'0000 to H'0FFC.
Similarly, to write H'0230 to the area 3 SDMR register, arbitrary data is written to address
H'FF940000 (address “Y”) + H'08C0 (value “X”) (= H'FF9408C0). As a result, H'0230 is written
to the SDMR register. The range of value “X” is H'0000 to H'0FFC.
The lower 16 bits of the address are set in the synchronous DRAM mode register.
When the bus width is 32 bits, the burst length is 4* and 8. When the bus width is 64 bits, the burst
length is fixed at 4. When a setting is made in SDMR, byte-size writes are performed at the
following addresses.
Bus Width
Burst Length
CAS Latency
Area 2
Area 3
32
4*
1
2
3
1
2
3
1
2
3
H'FF900048
H'FF900088
H'FF9000C8
H'FF90004C
H'FF90008C
H'FF9000CC
H'FF900090
H'FF900110
H'FF900190
H'FF940048
H'FF940088
H'FF9400C8
H'FF94004C
H'FF94008C
H'FF9400CC
H'FF940090
H'FF940110
H'FF940190
32
64
8
4
For a 32-bit bus:
17 16 15 14 13 12 11 10
9
0
8
7
6
5
4
3
2
1
0
Address
0
0
0
0
0
0
0
0
LMO LMO LMO WT BL2 BL1 BL0
DE2 DE1 DE0
←
→
10 bits set in case of 32-bit bus width
For a 64-bit bus:
17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
Address
0
0
0
0
0
0
0
0
LMO LMO LMO WT BL2 BL1 BL0
DE2 DE1 DE0
←
→
10 bits set in case of 64-bit bus width
Rev. 6.0, 07/02, page 363 of 986
RENESAS [ RENESAS TECHNOLOGY CORP ]
