The successor to the Intel 8008. The 8080 had a 16-bit address bus and an 8-bit data bus. It had seven 8-bit registers (six which could also be combined as three 16-bit registers), a 16-bit stack pointer to memory which replaced the 8008's internal stack and a 16-bit program counter. It also had 256 I/O ports (so I/O devices could be connected without needing to allocate any addressing space as is required for memory mapped devices) and a signal pin that allowed the stack to occupy a separate bank of memory. Shortly after the 8080, the Motorola 6800 was introduced.