Rainbow Electronics W90N745CDG - Manual (Page 73)

W90N745CD/W90N745CDG
- 68 -
Continued.
BITS DESCRIPTION
[10:8] RESERVED -
[7] COMPBK
Number of component bank in SDRAM bank 0/1
Indicates the number of component bank (2 or 4 banks) in external
SDRAM bank 0/1.
0 = 2 banks
1 = 4 banks
[6:5] DBWD
Data bus width for SDRAM bank 0/1
Indicates the external data bus width connect with SDRAM bank 0/1
If DBWD = 00, the assigned SDRAM access signal is not generated
i.e. disable.
DBWD [6:5] Bits
0 0 Bank disable
0 1 8-bit (byte)
1 0 16-bit (half-word)
1 1 REVERSED
[4:3] COLUMN
Number of column address bits in SDRAM bank 0/1
Indicates the number of column address bits in external SDRAM
bank 0/1.
COLUMN [4:3] Bits
0 0 8
0 1 9
1 0 10
1 1 REVERSED
[2:0] SIZE
Size of SDRAM bank 0/1
Indicates the memory size of external SDRAM bank 0/1
SIZE [2:0] Size of SDRAM （Byte）
0 0 0 Bank disable
0 0 1 2M
0 1 0 4M
0 1 1 8M
1 0 0 16M
1 0 1 32M
1 1 0 64M
1 1 1 REVERSED