Whenever master wants to send data it first generates a request which has particular address of that slave. Here is an illustration of SPI:Įach slave has its own unique 7 to 10 bit address which master uses to identify them. SS (slave select) is used to make a particular slave awake with who master wants to communicate. In the entire process SCK (serial clock) plays a very important role, every slave device depends on this clock to read data from MOSI and respond through MISO. Master sends data via MOSI while slaves respond via MISO line. The entire communication is handled by master itself no slave can send data on its own will. In a SPI, at any given time there could be only one master device and several other slaves under it who only respond to master’s call. SS – Slave Select (line used to select slave to which master wants to communicate)

SCK – Serial Clock (clock provided by master device) MISO – Master In Slave Out (line though which salves responds back to the master) MOSI – Master Out Salve In (line though which master sends data to its slaves) Slave – Device other than master which utilises master’s clock to communicate Master – Device which provides clock for communication Before moving ahead here are some terms that you should be aware of: This is a synchronous type serial communication protocol which consists of two data lines (MOSI and MISO), one clock line (SCK) and a slave select line (SS). PART 2 - SPI (Serial Peripheral Interface)

Types of Serial Communication Protocols: There are various types of serial communication protocols being used in embedded industry. Asynchronous serial communication: This type of serial communication does not require any common clock source between the transmitter and receiver, both the sides work according to their independent clocks. Synchronous serial communication: In this type of communication both transmitter and receiver share a common clock to remain in sync with each other.

Serial communication can be further categorized into synchronous and asynchronous type. In Serial Communication, only communication is done serially rest everything, like processing of the data etc., happens in a parallel fashion i.e.

Serial communication types