[Gordonjcp]

There's a flag set in hardware when /INT is asserted. At this point you can smack /INT around all you want, you're not getting any more interrupts firing.

Once you're done you clear the flag, either explicitly in the CPU's "condition code register" in some chips or by using a specific "Return from Interrupt" opcode that works like a "normal" subroutine return but clears the flag.

We use the analogy of a doorbell to describe interrupts a lot. In truth it's like if your doorbell could only be rung once, until you open and shut the door.