I am using ssd1306 module I can't use spi control principle diagram look
Before heard hardware spi
This is to use hardware spi

CodePudding user response:

According to the data in this table is to see, is through the disconnect switch R1 and R3 to SPI and I2C is 4 line,

CodePudding user response:

That is now the connection is connecting the R3 R1 is disconnected

CodePudding user response:

Your four wire serial, that sounds like the 3 line serial refers to the SPI mode