Gregory's Server
#TIL In the mid-70s, General Instrument and Honeywell designed the CP1600 microprocessor, and it used an architecture largely based on the PDP-11. Like the PDP-11, CP1600 used MMIO, memory and I/O shared the same address space, and there was no dedicated I/O address space. So far so good, but in order to fit the CP1600 into a small DIP-40 package, it must multiplex all the address and data signals on the same pins, making the MMIO difficult and expensive to decode.
To solve the MMIO problem, a dedicated, low-cost I/O controller for the CP1600 was developed. It was named the Programmable Interface Controller - and thus the PIC microcontroller was born.
It's weird to see how everything is connected together. In a sense, PIC came and once dominated the embedded electronics world because of PDP-11...