Group 6 Flashcards
A signal to the processor emitted by the hardware or software indicating an event that needs
immediate attention.
Interrupts
What are the 3 main reasons why we use interrupts?
Low level programming concept, extremely important, irreplaceable
An electronic alerting signal is sent from the processor from an external device, like a disk controller or an external peripheral.
Hardware Interrupts
Caused either by an exceptional condition or a special instruction in the instruction set which causes an interrupt when it is executed by the processor.
Software Interrupts
What is the Meaning of ISR?
Interrupt Service Routine
What are the two types of Interrupt Modules?
Level Triggered, Edge Triggered
Recall that registers are special, fixed-size variables with hardware implications.
Timers
It is generated when a timer tries to exceed its maximum value and resets to 0.
Overflow Interrupt
It is called when the. value of the timer equals a specific value, set. by the user.
Compare Match Interrupt
What are the 3 Timer Modes?
Normal Mode, CTC (Clear Time on Compare) Mode, PWM (Phase Width Modulation) Mode
The timer starts at 0, goes to a maximum value, and then resets itself.
Normal Mode
On a compare match, we can configure the timer to reset itself to 0.
CTC (Clear Time on Compare) Mode
The mode in which the timers generate the output signals.
PWM (Phase Width Modulation) Mode
What is the meaning of OCR?
Output Compare Register
