Hardware signals that pause the main program to run a handler.
An interrupt signals an event, saves context, runs an ISR and returns. Vectors map sources to handlers; priorities and nesting resolve conflicts. Keep ISRs short, use volatile flags and avoid blocking calls. Latency determines real-time capability.
A UART receive interrupt stores a byte in a buffer.
Interrupts let a device get the processor's attention immediately, so systems can respond to events without constant polling.
Hardware signals that pause the main program to run a handler.
Interrupts let a device get the processor's attention immediately, so systems can respond to events without constant polling.
It should do the minimum work, such as clearing the flag and saving data, and leave longer processing to the main program.
Shared data can be corrupted if an interrupt changes it during main code, so critical sections and volatile variables are needed.
Typical applications include handling a button press without polling the input in a loop, receiving a byte from a serial port as soon as it arrives and reacting to a timer overflow to update a control loop.
Study "Cache memory" first (topic 59 of 104 in Electronics & Embedded). It covers the groundwork this topic builds on.
Edge vs level triggered. Debouncing. Critical sections disable interrupts.
A UART receive interrupt stores a byte in a buffer.
The next topic is "GPIO", which builds directly on this one.
It is classed as Intermediate in Electronics & Embedded (topic 60 of 104). It is an intermediate topic. Work through the beginner topics in Electronics & Embedded first.
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