8
／
30
HTE029A1
6.2
MCU Interface
6.2.1
MCU Serial Peripheral Interface (4-wire SPI)
The 4-wire SPI consists of SCLK (serial clock), SDIN (serial data), D/C# and CS#. D0 acts as SCLK and D1 acts as
SDIN.
Table -1 : Control pins of 4-wire Serial Peripheral interface
Function
CS# pin D/C# pin SCLK pin
Write command
L
L
↑
Write data
L
H
↑
Note:
↑ 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 6-1 : Write procedure in 4-wire Serial Peripheral Interface mode
CS#
D/C#
SDIN/
SCLK
SCLK(D0)
SDIN(D1)
D7
D6
D5
D4
D3
D2
D1
D0
DB1
DB2
DBn
