Data Sheet

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7-3-1-2) MCU Serial Interface (4-wire SPI)
The 4-wire SPI consists of serial clock SCLK, serial data SDIN, D/C#, CS#. In SPI mode, D0 acts as SCLK, D1 acts as SDIN.
Function
CS#
D/C#
SCLK
Write Command
L
L
↑
Write data
L
H
↑
Table 7-4-1-2: Control pins of 4-wire Serial Peripheral interface
Note 7-4: ↑stands for rising edge of signal
SDIN is shifted into an 8-bit shift register in the order of D7, D6, ... D0. The data byte in the shift register is written to the Graphic Display
Data RAM (RAM) or command register in the same clock. Under serial mode, only write operations are allowed.
Figure 7-4-1-2: Write procedure in 4-wire Serial Peripheral Interface mode