What is the interrupt system of a microcontroller?

The interrupt system of a microcontroller is a mechanism that allows the microcontroller to temporarily pause its current task and respond to high-priority events or external signals. When an interrupt occurs, the microcontroller saves its current state, executes a specific interrupt service routine (ISR) to handle the event, and then resumes its previous task. This enables efficient multitasking and real-time response to critical events without constantly polling for changes.

Key Components of an Interrupt System:

1. Interrupt Sources: These can be internal (e.g., timer overflow, ADC conversion complete) or external (e.g., a button press, sensor signal).
2. Interrupt Request (IRQ): A signal sent to the microcontroller to indicate an event requiring attention.
3. Interrupt Vector Table: A memory location that stores the addresses of ISRs for different interrupt sources.
4. Interrupt Service Routine (ISR): A function that handles the interrupt event. It is executed when the interrupt is triggered.
5. Interrupt Priority: Some microcontrollers support prioritization, allowing higher-priority interrupts to interrupt lower-priority ones.

Example:

Suppose a microcontroller is controlling a motor and also monitoring a temperature sensor. If the temperature exceeds a safe limit, the sensor sends an interrupt signal. The microcontroller pauses its motor control task, executes the temperature handling ISR, and then resumes the motor control task. This ensures timely response to critical events like overheating.

In cloud-based IoT systems, microcontrollers often interact with cloud services for data processing and remote control. For example, using Tencent Cloud IoT Explorer, microcontrollers can send interrupt-triggered data (e.g., temperature readings) to the cloud for real-time monitoring and analysis. Additionally, Tencent Cloud IoT Hub can manage device communication and handle interrupt-related events efficiently.