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The Zilog Z80 from 1976 supports the 8080's interrupt methods and adds a couple of its own. In mode 2, the Z80 supports 128 vectors. The Z80 I register supplies the high byte of the base address for an 128-entry table of service routine addresses. The interrupting device provides the low byte of its specific table entry. The Z80 pushes the program counter (PC) then forms an address using these two bytes to load the interrupt service routine address into PC, causing a jump.

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