Pic 16xxx

Originated at Harvard university for a Defense Department project, but was
beaten by a simpler and more reliable single memory design from Princeton.
The microelectronics division was eventually spun off into Arizona Microchip Technology (around 1985), with the PIC as its main product.

The PIC 16x is an 8 bit design made with slightly newer design techniques than other 8 bit CPUs. It lost out to more popular CPUs and was later sold to Microchip Technology. MT still sells it for small embedded applications (see description below).

PIC1654S

N-Channel silicon gate technology; MOS/LSI device containing RAM, I/O, and a central processing unit as well as customer-defined ROM on a single chip; single +5 V power supply; on-chip oscillator; real time clock / counter; arithmetic logic unit; used to scan keyboards, drive displays, control electronic games; motor control, telecommunication equipment, radios, television, consumer appliances, industrial timing and control applications;

4 MHz

*SOIC: Plastic Small Outline

PIC1655

N-Channel silicon gate technology; MOS/LSI device containing RAM, I/O, and a central processing unit as well as customer-defined ROM on a single chip; single +5 V power supply; on-chip oscillator; real time clock / counter; arithmetic logic unit; used to scan keyboards, drive displays, control electronic games; motor control, telecommunication equipment, radios, television, consumer appliances, industrial timing and control applications; user programmable; 32 8-bit RAM registers; 512 x 12 bit program ROM; 4 inputs, 8 outputs, 8 bi-directional I/O lines

4 MHz

PIC1670

N-Channel silicon gate technology; MOS/LSI device containing RAM, I/O, and a central processing unit as well as customer-defined ROM on a single chip; single +5 V power supply; on-chip oscillator; real time clock / counter; arithmetic logic unit; used to scan keyboards, drive displays, control electronic games; motor control, telecommunication equipment, radios, television, consumer appliances, industrial timing and control applications; user programmable; 64 8-bit RAM registers (16 special purpose registers); 1024 x 13 bit program ROM

4 MHz

PIC16C5x

EPROM-based 8-bit CMOS technology

4 - 8 MHz

*SOIC: Plastic small outline