Communication

In embedded systems, communication refers to the transfer of data between different components, such as between microcontrollers, sensors, and external devices.

Communication allows an embedded system to collect, process, and exchange information, either internally (within the system) or externally (with other systems or networks).

Communication Types

Depend on the physical layer communication categories:

• Wired
• Wireless
  And every physical types has 2 main categories:
• Serial communication
• Parallel communication
  And every category has communication mode:
• Simplex
• Half-Duplex
• Full-Duplex

Wired Communication

It involves a physical medium, such as cables or wires, to transmit data between devices. Common examples include copper wires, fiber optic cables, and connectors like USB or Ethernet cables.

Wireless Communication

It uses electromagnetic waves, such as radio or infrared, to transmit data without physical connections. This enables data exchange over long distances and in applications where mobility and flexibility are essential.

Communication Protocol

A communication protocol is a set of rules that define how data is exchanged between devices in a network.

In embedded systems and electronics, communication protocols are essential for coordinating the transfer of data between microcontrollers, sensors, actuators, and other devices.

They establish guidelines for timing, data format, error detection, and data integrity, enabling devices with different architectures and functions to communicate reliably.

Communication protocols fall broadly into two categories: serial and parallel.

Serial Communication

In serial communication, data is transmitted one bit at a time over a single line or channel, allowing long-distance communication with minimal wiring. Serial communication is slower than parallel but more efficient in terms of wiring and space, making it ideal for many embedded systems.
Examples:

• UART (Universal Asynchronous Receiver-Transmitter): An asynchronous protocol used in serial communication where data is transferred without a shared clock signal. Start and stop bits define each data frame, making it popular in devices where low data transfer rates are acceptable.

• I2C (Inter-Integrated Circuit): A synchronous protocol used for short-range communication between devices. It requires two lines: a data line (SDA) and a clock line (SCL). I2C supports multiple devices on the same bus and is widely used in sensors and low-speed devices.

• SPI (Serial Peripheral Interface): A synchronous protocol ideal for fast data transfer between a master device and one or more slave devices. It uses multiple lines (MOSI, MISO, SCK, and SS) and is known for its simplicity and high data transfer speed in short-range applications.

  Parallel Communication

  In parallel communication, multiple bits are sent simultaneously over multiple wires or lines. This type of communication is generally faster than serial but requires more wiring and is usually limited to shorter distances.
  Parallel protocols are typically used for high-speed data transfer over short distances, such as within a computer system.
  Example:

• PCI (Peripheral Component Interconnect) and Parallel ATA (Advanced Technology Attachment) are examples of parallel protocols used for connecting peripherals within computers.

Simplex Communication

It is one-way communication from fixed sender to fixed receiver, like car radio.

Half-Duplex Communication

It is a Two-way communication, but only one direction is working at a time, like Walkie-talkie

Full-Duplex Communication

it is a type of data transmission where two devices can send and receive data simultaneously. Unlike half-duplex (where devices take turns to communicate) or simplex (one-way communication), full-duplex allows for continuous, bidirectional data flow, making it ideal for applications that require real-time or high-speed communication.