National COP400
Developer	National Semiconductor
Manufacturer	National Semiconductor
Type	microcontrollers
Production	1977
ISA	COP400
Word size	4 bit 0.5 octets 1 nibbles
Technology	nMOS, CMOS
Clock	4.098 kHz-500 kHz
Package	DIP16, DIP20, DIP24, DIP28, DIP40

The COP400 or COPS II or simply COPS (Controller Oriented Processor System II) was a family of 4-bit microcontrollers developed by National Semiconductor. The family was introduced a year after the COPS I in 1977. Components in the COPS II were made in nMOS and CMOS technology instead of pMOS as used in COPS I. The COPS II obsoleted the COPS I family soon after release.

In later 1981 National Semiconductor introduced a number of dual-core microcontrollers, one of the earliest instances of multiple CPUs in on single integrated circuit.

2nd sources

• Western Digital
• SGS-Thomson
• Texas Instruments

Members

Part	ROM	RAM	Frequency	Package	Notes
COP310C	512 B	128 b	4.098 kHz - 62.5 kHz	DIP24	CMOS, extended temperature version of 410
COP311C	512 B	128 b	4.098 kHz - 62.5 kHz	DIP16	CMOS, extended temperature version of 411
COP324C	2,048 B	512 b	62.5 kHz - 250 kHz	DIP28	extended temperature version of 424
COP325C	2,048 B	512 b	62.5 kHz - 250 kHz	DIP24	extended temperature version of 425
COP326C	2,048 B	512 b	62.5 kHz - 250 kHz	DIP20	extended temperature version of 426
COP402		256 b	250 kHz - 500 kHz	DIP40	ROM-less version of COP420, for prototyping
COP402M		256 b	250 kHz - 500 kHz	DIP40	ROM-less version of COP420, for prototyping, for MICROBUS
COP404L		512 b	250 kHz - 500 kHz	DIP28	ROM-less version of COP444L, for prototyping
COP410L	512 B	128 b	4.098 kHz - 62.5 kHz	DIP24
COP410C	512 B	128 b	4.098 kHz - 62.5 kHz	DIP24	CMOS version of 410
COP411L	512 B	128 b	4.098 kHz - 62.5 kHz	DIP16
COP411C	512 B	128 b	4.098 kHz - 62.5 kHz	DIP16	CMOS version of 411
COP413L	512 B	128 b	4.098 kHz - 62.5 kHz	DIP20
COP413L	512 B	128 b	4.098 kHz - 62.5 kHz	DIP20	CMOS version of 413
COP414L	512 B	128 b	4.098 kHz - 62.5 kHz	DIP20
COP420	1,024 B	256 b	250 kHz - 500 kHz	DIP28
COP420L	1,024 B	256 b	62.5 kHz - 250 kHz	DIP28	Low-power version
COP420C	1,024 B	256 b	4.098 kHz - 62.5 kHz	DIP28	CMOS version of 420
COP421	1,024 B	256 b	250 kHz - 500 kHz	DIP24	Identical to COP420, but DIP24
COP421L	1,024 B	256 b	62.5 kHz - 250 kHz	DIP24	Low-power version
COP424C	2,048 B	512 b	62.5 kHz - 250 kHz	DIP28	Enhanced version of COP420, obsoleted it
COP425C	2,048 B	512 b	62.5 kHz - 250 kHz	DIP24
COP426C	2,048 B	512 b	62.5 kHz - 250 kHz	DIP20
COP444L	2,048 B	512 b	250 kHz - 500 kHz	DIP28	Identical to COP420, twice the memory (2xROM/2xRAM)
COP444C	2,048 B	512 b	250 kHz - 500 kHz	DIP28	CMOS version of 444
COP445L	2,048 B	512 b	250 kHz - 500 kHz	DIP24	Identical to COP444L, but DIP24
COP445C	2,048 B	512 b	250 kHz - 500 kHz	DIP24	CMOS version of 445
DIP28 and DIP24 chips are architecturally identical; 4 IN ports are simply omitted on the smaller package.

Dual cores

Announced in 1981 and manufactured later that year, National introduced a number of dual-core microcontrollers. While primitive by today's standard (no notion of mutual exclusion), those chips were true dual core - perform calculations independently of each other and capable of accessing the same ROM, RAM, and I/O ports.

Part	ROM	RAM	Frequency	Package	Notes
COP2404					ROM-less version of COP2440, for prototyping
COP2440	2,048 B
COP2441
COP2442

Design

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COP400 ISA

Main article: COP400 ISA

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Documents

• National COPS400 Databook

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