Connecting peripherals to a processor is a crucial process in computer systems. It allows the processor to communicate with and control various input and output devices such as keyboards, mice, printers, and storage devices. There are several methods for connecting peripherals to the processor, but the most common one is through external interrupts.

External Interrupts:
External interrupts are signals generated by the peripherals to gain the attention of the processor. When a peripheral needs to communicate with the processor, it sends an interrupt signal to the processor. This signal interrupts the normal execution of the processor and directs it to a specific interrupt handling routine. The interrupt handling routine is a piece of code that is responsible for processing the request from the peripheral.

Advantages of External Interrupts:
- Scalability: External interrupts provide a scalable solution as multiple peripherals can share the same interrupt line. Each peripheral is assigned a unique interrupt number, allowing the processor to identify the source of the interrupt and execute the corresponding interrupt handling routine.
- Real-time response: External interrupts enable real-time response as the processor can immediately respond to the interrupt request from the peripheral. This is particularly important for time-sensitive applications where delay can result in data loss or system failure.
- Efficient resource utilization: External interrupts help in efficient resource utilization as the processor does not need to constantly poll the peripherals for data. Instead, it can focus on other tasks and only respond when an interrupt occurs.

Other Methods:
While external interrupts are the most common method, there are other ways to connect peripherals to the processor as well:
- Internal interrupts: Internal interrupts are generated within the processor itself and are used to handle internal events or exceptions. These interrupts are not related to the peripherals.
- Software: Some peripherals may require software-based communication protocols. In such cases, the processor communicates with the peripheral using specific software instructions or protocols.
- Exceptions: Exceptions are abnormal events or conditions that occur during the program's execution. They can be triggered by various factors such as arithmetic errors, memory access violations, or divide-by-zero errors. Exceptions are not specifically related to peripheral communication but can interrupt the normal execution flow of the processor.

In conclusion, while there are multiple methods for connecting peripherals to the processor, the most common and efficient method is through external interrupts. External interrupts allow peripherals to send interrupt signals to the processor, enabling real-time response and efficient resource utilization.