10 SDRAM CONTROLLER (SDRAMC)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
10-3
4.2.1 SDRAM Setup Items
Table 10.
Item
Setting contents
Control bit settings
SDRAM address
configuration
32M
×
16 bits
×
1
ADDRC[2:0]/SDRAMC_CFG register = 0x7
16M
×
16 bits
×
1
ADDRC[2:0]/SDRAMC_CFG register = 0x3
8M
×
16 bits
×
1
ADDRC[2:0]/SDRAMC_CFG register = 0x2
4M
×
16 bits
×
1
ADDRC[2:0]/SDRAMC_CFG register = 0x1
1M
×
16 bits
×
1 (default)
ADDRC[2:0]/SDRAMC_CFG register = 0x0 (default)
16M
×
8 bits
×
2
ADDRC[2:0]/SDRAMC_CFG register = 0x6
8M
×
8 bits
×
2
ADDRC[2:0]/SDRAMC_CFG register = 0x5
CAS latency
3, 2, or 1
CAS[1:0]/SDRAMC_APP register = 0x3, 0x2 or 0x1
Burst length
2 (fixed)
–
t
RP
, t
RCD
1 (default) to 4 cycles
T24NS[1:0]/SDRAMC_CFG register = 0x0 (default) to 0x3
t
RAS
1 (default) to 8 cycles
T60NS[2:0]/SDRAMC_CFG register = 0x0 (default) to 0x7
t
RC
, t
RFC
, t
XSR
1 to 16 cycles (default: 15 cycles) T80NS[3:0]/SDRAMC_CFG register = 0x0 to 0xf (default: 0xe)
SDRAM address configuration
Use ADDRC[2:0]/SDRAMC_CFG register to select the SDRAM size and chip configuration. This selection
also sets up the bank size, column address size (page size), and row address size.
4.2.2 SDRAM Size Selections and SDRAM Address
Table 10.
ADDRC[2:0]
0x0 (default)
0x1
0x2
0x3
0x7
0x4
0x5
0x6
SDRAM device
16-bit device
–
Two 8-bit devices
Capacity (M bit)
16
64
128
256
512
–
64
×
2
128
×
2
Data width
16 bits
Row size
2048
4096
4096
8192
8192
–
4096
4096
Column size
256
256
512
512
1024
–
512
1024
Number of banks
2
4
4
4
4
–
4
4
A25
–
–
–
–
R10
–
–
–
A24
–
–
–
R12
R12
–
–
R11
A23
–
–
R11
R11
R11
–
R11
R10
A22
–
R11
R9
R9
R9
–
R9
R9
A21
–
R8
R8
R8
R8
–
R8
R8
A20
R7
R7
R7
R7
R7
–
R7
R7
A19
R6
R6
R6
R6
R6
–
R6
R6
A18
R5
R5
R5
R5
R5
–
R5
R5
A17
R4
R4
R4
R4
R4
–
R4
R4
A16
R3
R3
R3
R3
R3
–
R3
R3
A15
R2
R2
R2
R2
R2
–
R2
R2
A14
R1
R1
R1
R1
R1
–
R1
R1
A13
R0
R0
R0
R0
R0
–
R0
R0
A12
R10
R10
R10
R10
B1
–
R10
B1
A11
R9
R9
B0
B0
B0
–
B0
B0
A10
R8
B1
B1
B1
C9
–
B1
C9
A9
B0
B0
C8
C8
C8
–
C8
C8
A8
C7
C7
C7
C7
C7
–
C7
C7
A7
C6
C6
C6
C6
C6
–
C6
C6
A6
C5
C5
C5
C5
C5
–
C5
C5
A5
C4
C4
C4
C4
C4
–
C4
C4
A4
C3
C3
C3
C3
C3
–
C3
C3
A3
C2
C2
C2
C2
C2
–
C2
C2
A2
C1
C1
C1
C1
C1
–
C1
C1
A1
C0
C0
C0
C0
C0
–
C0
C0
A0
DQM
DQM
DQM
DQM
DQM
–
DQM
DQM
When reading/writing byte data, the SDRAMC decodes A0/#BSL and #WRH/#BSH into DQML and DQMH.
Upper address bits that are not used (depending on memory size) are all fixed to 0.