Intel MCS-48

Because of this, it is used in high-volume, cost-sensitive consumer electronics devices such as TV remotes, computer keyboards, and toys.

The MCS-48 series was commonly used in computer and terminal keyboards, converting key presses into protocols that can be understood by digital circuits.

This also allows the possibility of serial communication, reducing the amount of conductors needed in cables on external keyboards.

The Sinclair QL used the closely related Intel 8049 to manage its keyboard, joystick ports, RS-232 inputs and audio.

The ROM-less 8035 variant was used in Nintendo's arcade game Donkey Kong to generate the background music.

Philips Semiconductors (now NXP) owned a license to produce this series and developed their MAB8400-family based on this architecture.

Intel 8048 microcontroller
The 8749 with UV EPROM
An Intel 8049 microcontroller, as used in a HP3478A multimeter. This chip was manufactured in the second week of 1984.
Intel 8749 die
Intel P8242 - keyboard controller with Phoenix firmware for AT-compatible computers
National Semiconductor NS87P50D-6 – Second source for the 87P50 piggyback microcontroller