W90N745CD Datasheet, PDF (64/422 Pages) Winbond – 16/32-bit ARM microcontroller

W90N745CD/W90N745CDG
6.3.2.2. SDRAM Power Up Sequence
The SDRAM must be initialized predefined manner after power on.W90N745 SDRAM Controller
automatically executes the commands needed for initialion and set the mode register of each bank to
default value. The default value is：
— Burst Length = 1
— Burst Type = Sequential (fixed)
— CAS Latency = 2
— Write Burst Length = Burst (fixed)
The value of mode register can be changed after power up sequence by setting the value of
corresponding bank’s configuration register “LENGTH” and “LATENCY” bits and set the MRSET bit
enable to execute the Mode Register Set command.
6.3.2.3. SDRAM Interface
A[20:0]
D [1 5 :0 ]
M CLK
MCKE
nSCS[1:0]
nSRAS
nSCAS
nSW E
nSDQM [1:0]
W 90N745
A [ 1 0 :0 ]
A13
A14
nSCS0
nSDQM [1:0]
A [1 0 :0 ]
BS0
BS1
DQ [[15:0]
CLK
CKE
nCS
nRAS
nCAS
nW E
DQM [1:0]
SDRAM
32Mb 512Kx4x16
Figure 6.3.1 SDRAM Interface
Publication Release Date: September 22, 2006
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Revision A2