In 1974 National Semiconductor introduced what is arguably the first 16-bit microprocessor (it had a 8-bit mode as well which was more efficient but could run 16-bits as well). This chip was made on a PMOS process and ran at 1.3MHz. In some ways it was ahead of its time, there wasn’t a ton of demand for a 16-bit processor at the time and interfacing to its PMOS architecture was…tricky.
