Datasheet

7-3-2-3) MCU Serial Interface (3-wire SPI)
The 3-wire serial interface consists of serial clock SCLK, serial data ADIN and CS#.
In 3-wire SPI mode, D0 acts as SCLK, D1 acts as SDIN, The pin D/C# can be connected to an external ground.
The operation is similar to 4-wire serial interface while D/C# pin is not used. There are altogether 9-bits will be shifted into the shift
register on every ninth clock in sequence: D/C# bit, D7 to D0 bit. The D/C# bit (first bit of the sequential data) will determine the
following data byte in shift register is written to the Display Data RAM (D/C# bit = 1) or the command register (D/C# bit =
0).Under serial mode, only write operations are allowed.
Table 7-3: Control pins of 3-wire Serial Peripheral Interface
Note 7-5: ↑stands for rising edge of signal
Figure 7-2: Write procedure in 3-wire Serial Peripheral Interface mode
Function CS# D/C# SCLK
Write Command L Tie LOW ↑
Write data L Tie LOW ↑
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