8 levels of interrupts.
- Can be cascaded in master-slave configuration to handle 64 levels of interrupts.
- Internal priority resolver.
- Fixed priority mode and rotating priority mode.
- Individually maskable interrupts.
- Modes and masks can be changed dynamically.
- Accepts IRQ, determines priority, checks whether incoming priority > current level being serviced, issues interrupt signal.
- In 8085 mode, provides 3 byte CALL instruction. In 8086 mode, provides 8 bit vector number.
- Polled and vectored mode.
- Starting address of ISR or vector number is programmable.
- No clock required
Pin diagram
