Have you heard of SP2?

Have you heard of SP2?

Today, we will take a look at the basics of serial peripheral interface (SPI) communication and its four main operating modes.

SPI is one of the most widely used communication protocols in serial communication, typically used to communicate with memory, converters, real-time clocks, sensors, audio chips, and more.

SPI is also a synchronous communication protocol with communication speeds of up to 8 megabits per second and possibly even higher, as it supports higher clock frequencies.

Furthermore, SPI communication is a full-duplex communication and has a master-slave configuration. In this mode, two devices communicating with each other can simultaneously send and receive data because SPI communication does not rely on a single data line. In SPI communication, a master device can be connected to multiple slave devices, and each level has four lines connected to the host. The first line, called MOSI, represents the host sending data to the second base of the slave. The second line, called MISO, represents the slave sending data to the host. The third line is called SCK and represents a synchronization line.

Lastly, the chip select line has as many lines as there are slave devices available.

The chip select lines are initially set to a high logic level, which is equivalent to VC. When the master device needs to communicate with a particular slave device, it simply pulls the corresponding chip select line to a low logic level to notify the slave device that data transmission is about to begin.

There are four different clock mode combinations in SPI, depending on the clock polarity and clock phase. Mode 0 has a clock polarity and clock phase of zero, indicating that the clock is at a low logic level when idle and data is sampled on the rising edge of the clock.

Mode 1 has a clock polarity of zero and a clock phase of one, indicating that the clock is at a low logic level when idle and data is sampled on the falling edge of the clock.

Mode 2 has a clock polarity of one and a clock phase of zero, indicating that the clock is at a high logic level when idle and data is sampled on the falling edge of the clock.

In the final mode 3, the clock polarity and clock phase are both one, indicating that the clock is at a high logic level when idle and data is sampled on the rising edge of the clock.