Serial communication is an essential part of computer architecture – it allows for the effective exchange of data between two or more devices. It is used for many applications, such as in micro controllers and embedded systems, where it is used to store and transmit data, control peripherals and connect to the Internet. In this article, we’ll take a closer look at what serial communication is, how it works and its applications.
Serial communication typically involves a single data wire that carries a stream of data packets, which can then be read by devices with suitable serial interfaces. This single data wire carries binary data, which are typically arranged in 8-bit bytes. These 8-bit bytes represent a single character, such as a letter, number or symbol. The advantage of serial communication is that it requires fewer connections compared to other digital communication protocols, and is therefore cheaper and less complex to implement.
Before serial communication was possible, devices used to communicate using parallel communication – which required multiple wires in order to transmit data simultaneously. However, this was more expensive and harder to implement than serial communication, and so serial communication has become the preferred protocol for embedded systems and micro controllers.
Serial communication works by the transmission of data bits over the same data wire. This means that the device sending the data must be able to send the data bits in a specific order, while the receiving device must be able to read the data bits in the same order. This process is known as synchronous serial communication. Asynchronous serial communication is also possible, where the data bits are not transmitted in a specific order, but rather sent as soon as they are available.
Serial communication is used in many applications, including computer networks, robotics, remote data collection, industrial process control, and medical devices. It is also often used to connect micro controllers and embedded systems to the Internet, as it offers more efficient data transfer than other protocols. Serial communication is also more reliable than other protocols, as data can be transmitted without interference from external sources, such as electromagnetic interference.
Serial communication is a critical part of any computer architecture, as it allows for the efficient, effective exchange of data. It is often used in embedded systems and micro controllers, as well as for connecting to the Internet, and has numerous applications in various industries. Understanding how it works and its advantages can help developers and engineers make better use of this protocol in their projects.
Data Rates
The speed at which the data is sent and received is referred to as the data rate. Serial communication protocols typically use variable-rate protocols, which means that the data rate can vary with certain factors, such as the distance between the sending and receiving devices, the type of cable used, and the amount of traffic on the network. This flexibility of the data rate makes it an ideal choice for applications that require varying data rates.
The most common data rates used in serial communication protocols are 9600, 19200, 38400, and 115200 bits per second (bps). Depending on the complexity of the application, the data rate may need to be increased in order to send and receive data more quickly. Some protocols, such as RS-232, can also support higher data rates of up to 115200 kbps.
For applications where data needs to be sent and received quickly, such as in industrial automation, it may be best to use higher data rates. Higher data rates allow for faster and more efficient data transfer, which can be beneficial in complex applications. However, these higher data rates also come with an increase in power consumption.
Fault Tolerance
Fault tolerance is a feature of serial communication protocols designed to reduce the chances of data loss due to transmission errors. Fault tolerance is achieved by using error detection and correction protocols such as Cyclical Redundancy Checks (CRCs). These protocols ensure that data is sent correctly and that any errors that occur during transmission are detected and corrected.
Fault tolerance is not a feature of all serial communication protocols, and so it is important to consider this when choosing a protocol for a particular application. For applications where data accuracy is paramount, such as in medical or industrial automation, a protocol with fault tolerance may be the best choice.
When considering fault tolerance, it is also important to consider whether the protocol supports hardware flow control. This is a feature that allows the data to be sent and received over the same connection and helps to prevent data loss caused by buffer overflows. Hardware flow control is not supported by all serial communication protocols, so it is important to check before selecting a protocol.
Choosing The Right Protocol
When choosing a serial communication protocol for a particular application, it is important to consider the type of data that will be sent and received. Different protocols may offer different features, so it is important to select the protocol that best suits the required application. For example, if the transmission of data needs to be extemely accurate, then a protocol with fault tolerance may be the best choice.
It is also important to consider the data rate that is required for the application. Different protocols offer different data rates, so it is important to select the protocol that best meets the demands of the application. For most applications, the data rate should be high enough to facilitate efficient data transfer, while being low enough to optimise power consumption.
In addition to these considerations, it is also important to take into account the hardware and software requirements of the application. Different serial communication protocols may have different hardware or software requirements, or may require the use of specific drivers or hardware devices. It is important to research these requirements before selecting a protocol, in order to make sure that the right protocol is chosen for the application.
Data Security
Data security is an important consideration for any application that involves the transmission of sensitive data. Even though most serial communication protocols are relatively secure, it is still important to take steps to ensure that the data is protected. This can be done by using encryption protocols, such as Secure Sockets Layer (SSL) or Transport Layer Security (TLS), and by making sure that the data is not exposed to any malicious third parties.
Data security is also important when connecting to the Internet. When using a serial communication protocol to connect to the Internet, it is important to make sure that the data is securely transmitted and stored. This can be achieved by using secure communication protocols, such as IPsec, which encrypts the data before it is sent, and by using secure servers to store the data.
Controller Area Network
Controller Area Network (CAN) is a serial communication protocol developed by Bosch, which is often used in automotive applications. CAN is an efficient and reliable protocol that is used in a variety of systems, such as in powertrain, braking, and infotainment systems in cars. It is designed to be a robust protocol and is highly resistant to interference from other systems or devices.
CAN is a multi-master protocol and can support communication with up to sixteen devices. This makes it ideal for use in distributed systems and applications that need to communicate with multiple devices. It is also a low-bandwidth protocol, which means that it can be used in applications where data needs to be sent and received over limited bandwidth.
In addition to its low bandwidth requirements, CAN is also a deterministic protocol, which allows data to be sent and received with minimal latency. This makes it well suited for applications such as real-time control and data acquisition, where instantaneous response times are important. It is also a fault-tolerant protocol, which makes it reliable for mission critical applications.
Summary
Serial communication is an essential part of any computer architecture, providing a fast and efficient way to transmit data between two or more devices. It has numerous applications, from micro controllers and embedded systems to industrial and medical applications, and is also often used to connect to the Internet. Understanding how serial communication works and its advantages can help developers and engineers make the most of this protocol.
Data rates are an important part of serial communication, with variable rate protocols allowing the data rate to vary depending on the application. Fault tolerance is also an important feature of some serial communication protocols, allowing data to be sent and received with minimal errors. When choosing a serial communication protocol, it is important to consider the type of data that will be sent, the hardware and software requirements, and the data rate that is required.
Controller Area Network (CAN) is a popular serial communication protocol, often used in automotive applications. CAN is an efficient and reliable protocol, with low bandwidth requirements and deterministic performance, making it well-suited for sending and receiving data in real-time with minimal latency. It is also a fault-tolerant protocol, making it reliable for mission critical applications.
