MCS-4

The MCS-4 (Micro-Computer Set-4) or 4000 Series or Busicom Chip Set was a family of 4-bit microprocessor chipsets developed by Intel. The entire chipset was made of four individual chips, including the 4004 CPU which became the first commercial microprocessor. MCS-4 was completed by March 1971, entered production in June, and introduced into the market on November 15, 1971.

Intel

Part	Description	Photo
4001	ROM
4002	RAM
4003	shift register
4004	MPU
4008	Address latch
4009	I/O Interface

White Ceramic - Grey Trace 

	C4001	C4002-1	C4002-2	C4003	C4004
Grey Trace
Normal
Half Round Key

White Ceramic - Normal

C4001	C4002-1	C4002-2	C4003	C4004

White Ceramic - Half Round Key

C4001	C4002-1	C4002-2	C4003	C4004

White Ceramic - Black Dot

C4001	C4002-1	C4002-2	C4003	C4004
Black Dot

White Ceramic - 5 Series Left Grounding

C4001	C4002-1	C4002-2	C4003	C4004

White Ceramic - 5 Series Right Grounding

C4001	C4002-1	C4002-2	C4003	C4004

Grey Ceramic

C4001	C4002-1	C4002-2	C4003	C4004

Plastic

	C4001	C4002-1	C4002-2	C4003	C4004
Black
Grey
Yellow Print		Black Grey	Black Grey	Black	Black

Plastic MCS-4 - Full Set

National Semiconductor (2nd Source)

White Ceramic

Variant	INS4001D	INS4002-1D	INS4002-2D	INS4003D	INS4004D
No Grounding
Left Grounding

Gold

INS4001D	INS4002-1D	INS4002-2D	INS4003D	INS4004D

Purple Ceramic

Variant	INS4001D	INS4002-1D	INS4002-2D	INS4003D	INS4004D
Gold Pins - SL
Silver Pins - NS
Silver Pins - SL

Grey Ceramic

INS4001D	INS4002-1D	INS4002-2D	INS4003D	INS4004D

Plastic

Logo	INS4001D	INS4002-1D	INS4002-2D	INS4003D	INS4004D
NS Logo
Squiggly Line