Interrupts in 8085 Microprocessor: Vectored-Non Vectored Interrupts And Maskable-Non Maskable Interrupts
Vectored Interrupt: In vectored interrupts, the manufacturer fixes the address of the ISR to which the program control is to be transferred. the processor automatically branches to the specific address in response to an interrupt. • The TRAP, RST 7.5, RST 6.5 and RST 5.5 are vectored interrupts. Non-Vectored Interrupt: But in non-vectored interrupts the interrupted device should give the address of the interrupt service routine (ISR). • The INTR is a non-vectored interrupt. Hence when a device interrupts through INTR, it has to supply the address of ISR after receiving interrupt acknowledge signal. Maskable & Non-Maskable Interrupt: The hardware vectored interrupts are classified into maskable and non-maskable interrupts. • TRAP is non-maskable interrupt. • RST 7.5, RST 6.5 and RST 5.5 are maskable interrupt. Masking is preventing the interrupt from disturbing the main program. When an interrupt is masked the processor will not accept the interrupt signal. The interrupts ca