Understanding the Polling Method for Embedded Systems
What Is Polling Method in Embedded System?
Polling method is a software technique used in embedded systems that detects changes within the system and allows devices to react accordingly. It is commonly used in embedded systems as it helps to save energy and is easy to implement.
The polling method works by checking for changes in the system, either through regular intervals or on specific triggers. For example, a processor in an embedded system may have a certain task to perform, such as a certain calculation or transfer of data to another device. The processor will then check for the completion of the task at certain intervals. If the task has been completed, it can move on to the next one. If not, it can continue to wait until the task has been completed.
Polling methods are particularly useful when dealing with processes that take a long time to complete, or when dealing with inputs from multiple sources that need to be processed quickly. This is because they allow the system to detect changes without having to constantly monitor them.
In addition to being energy-efficient, using the polling method can also help to reduce latency when processing multiple tasks. The processor doesn’t need to wait for a response from a certain device, giving it more time to process other tasks.
Overall, the polling method is an efficient way to handle processes and inputs within an embedded system. It saves energy and reduces latency, making it a powerful tool for embedded system developers.
Application of polling method in embedded system
Polling is a common technique used in embedded systems to interact with peripheral devices. It involves repeatedly checking the status of a device or input signal to determine if an event has occurred or if data is available.
The following are some common applications of polling in embedded systems:
-
Reading Input Signals: Polling is commonly used to read input signals from sensors, switches, and other devices. In this application, the microcontroller repeatedly checks the status of the input pin and takes appropriate action based on the input state.
-
Communication with Peripherals: Polling is often used to communicate with peripherals such as serial ports, I2C, and SPI devices. In this application, the microcontroller repeatedly checks the status of the peripheral to determine if data is available to read or write.
-
Timing: Polling can be used to implement simple timing functions, such as measuring a delay between two events. In this application, the microcontroller repeatedly checks the time elapsed since the start of an event and takes action when the desired delay has been reached.
-
Resource Management: Polling can also be used for resource management in embedded systems. For example, a microcontroller can poll a shared resource such as memory or a communication bus to determine if it is available for use.
While polling is a simple technique, it can lead to inefficient use of processing resources, particularly when multiple devices need to be polled frequently. Interrupt-driven techniques are often used instead, as they allow the microcontroller to respond immediately when an event occurs, rather than wasting time repeatedly checking the status of a device.