What is masking and why it is needed in microprocessor?

What is masking and why it is needed in microprocessor?

It provides the ability for selectively disabling the interrupts. An interrupt pin which is already masked cannot interrupt, even though the interrupt pin is still in active state and the interrupts which are generally enabled using the EI set of instructions.

What is masking of interrupt in microprocessor?

Masking of Interrupts in 8085 microprocessor is most important portion of interrupt. In 8085 microprocessor masking of interrupt we can do for four hardware interrupts INTR, RST 5.5, RST 6.5, and RST 7.5. So no interrupt recognized by the hardware reset. The interrupts can enabled by the EI instruction.

What do you mean by masking the interrupt how it is activated in 8085?

Maskable Interrupts are those which can be disabled or ignored by the microprocessor. These interrupts are either edge-triggered or level-triggered, so they can be disabled. INTR, RST 7.5, RST 6.5, RST 5.5 are maskable interrupts in 8085 microprocessor. TRAP is a non-maskable interrupt.

What is masking and unmasking of interrupts?

Masking an interrupt does not clear or disable the interrupt. If a GPIO interrupt is enabled, active, and masked, unmasking this interrupt causes the GPIO controller device to signal an interrupt request to the processor. A GPIO interrupt mask bit has no effect while the GPIO interrupt is disabled.

Which of the instruction is used to selectively mask an interrupt?

Answer: SIM Instruction: The SIM instruction generally used to mask or unmask RST hardware interrupts. When it executed, the SIM instruction reads the content of accumulator and accordingly mask or unmask the interrupts.

What is mask register?

The mask register modifies the pattern in the pattern register by masking certain bits in the pattern. The SEARCH command searches for all words that match the part of the pattern that is not masked.

What is the meaning of maskable?

maskable in British English (ˈmɑːskəbəl) adjective. capable of being masked.

What is meant by non-maskable interrupts?

In computing, a non-maskable interrupt (NMI) is a hardware interrupt that standard interrupt-masking techniques in the system cannot ignore. It typically occurs to signal attention for non-recoverable hardware errors. Some NMIs may be masked, but only by using proprietary methods specific to the particular NMI.

What are maskable and non maskable interrupts give examples how will you mask an interrupt in 8086?

The 8086 has two hardware interrupt pins, i.e. NMI and INTR. NMI is a non-maskable interrupt and INTR is a maskable interrupt having lower priority. One more interrupt pin associated is INTA called interrupt acknowledge.

What are maskable and non-maskable interrupts give examples how will you mask an interrupt in 8086?

Which instruction is not masking and masking of interrupt instruction?

If MSE bit = 0, SIM instruction is not being used for masking or unmasking of interrupts. In such a case, the LS 3bits of the Accumulator are not having any useful information. If MSE bit = 1, the SIM instruction is used for masking or unmasking of interrupts.

Which is non-maskable interrupt?

What is the point of masking and unmasking interrupts in interrupt handling?

What is the point of masking and unmasking interrupts in interrupt handling? It kind of depends on the system. What masking does is protect critical sections of code from being used while that code is modifying some specific data. But it also depends on the system as simple masking causes a system slowdown…

How to check if an interrupt is maskable?

The interrupt enable register (IER) is checked to ensure that the interrupt is enabled. The interrupt mask register (INTM) is checked to be sure that the interrupt is not masked. The interrupt flag register (IFR) corresponding to the flag is cleared. Appropriate registers are saved as context.

What happens if I don’t mask the timer?

If I didn’t mask that timer, it might have been enabled and continued making interrupts which would slow down my code. Another example was that I would use the UART receive REGISTER full interrupt and so would never need the UART receive BUFFER full interrupt to occur.

What happens when you unmask a GPIO interrupt?

Later, after the ISR runs and clears the interrupt, the interrupt can be safely unmasked. Masking an interrupt does not clear or disable the interrupt. If a GPIO interrupt is enabled, active, and masked, unmasking this interrupt causes the GPIO controller device to signal an interrupt request to the processor.