What is EI in microprocessor 8085?

In the 8085 microprocessor, EI stands for "Enable Interrupt." It is an instruction used to enable the interrupt system, allowing the microprocessor to recognize and respond to external interrupt requests. When the EI instruction is executed, the microprocessor sets the interrupt enable flip-flop, permitting it to accept interrupts after the current instruction is completed. This is crucial for handling asynchronous events and multitasking in embedded systems.