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7.3inch e-Paper (E)
User Manual
15
7-3-1-2 MCU SERIAL INTERFACE (4-WIRE SPI)
The 4-wire SPI consists of serial clock SCLK, serial data SDA, D/C#, CS#.
Function
CS#
D/C#
SCLK
Write Command
L
L
↑
Write data
L
H
↑
Table 7-2: Control pins of 4-wire Serial Peripheral interface
Note 7-5: ↑stands for rising edge of signal
SDA 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 7-1: Write procedure in 4-wire Serial Peripheral Interface mode