- The Intel 8086 microprocessor (1978) started the x86 architecture that continues to this day. In this blog post, I’m focusing on a small part of the chip: the address and data pins that connect the chip to external memory and I/O devices. In many processors, this circuitry is straightforward, but it is complicated in the 8086 for two reasons. First, Intel decided to package the 8086 as a 40-pin DIP, which didn’t provide enough pins for all the functionality. Instead, the 8086 multiplexes address, data, and status. In other words, a pin can have multiple roles, providing an address bit at one time and a data bit at another time.