Am2900 is a family of integrated circuits (ICs) created in 1975 by Advanced Micro Devices (AMD). They were constructed with bipolar devices, in a bit-slice topology, and were designed to be used as modular components each representing a different aspect of a computer control unit (CCU). By using the bit slicing technique, the Am2900 family was able to implement a CCU with data, addresses, and instructions to be any multiple of 4 bits by multiplying the number of ICs. One major problem with this modular technique was that it required a larger number of ICs to implement what could be done on a single CPU IC. The Am2901 chip was the arithmetic logic unit (ALU), and the "core" of the series. It could count using 4 bits and implement binary operations as well as various bit-shifting operations. The 2901 and some other chips in the family were second sourced by an unusually large number of other manufacturers, starting with Motorola and then Raytheon both in 1975 and also Cypress Semiconductor, National Semiconductor, NEC, Thomson, and Signetics. In the Soviet Union and later Russia the Am2900 family was manufactured as the 1804 series (with e.g. the Am2901 designated as KR1804VS1 / ) which was known to be in production in 2016. Computers made with Am2900-family chips There are probably many more, but here are some known machines using these parts: The Apollo Computer Tern family: DN460, DN660 and DSP160. All used the same system board emulating the Motorola 68010 instruction set. The Itek Advanced Technology Airborne Computer (ATAC) used on the Galileo Attitude and Articulation Control Computer System and some Navy aircraft had a 16-register, 16-bit word width assembled from 4-bit-wide 2900 series processors. Four special instructions were added to the Galileo version of the ATAC, and later some chips were replaced with radiation-hardened 2901 chips. Data General Nova 4, which obtained 16-bit word width using four Am2901 ALUs in parallel; one of the boards had 15 Am2901 ALUs on it. Digital Equipment Corporation (DEC) PDP-11 models PDP-11/23, PDP-11/34, and PDP-11/44 floating-point options (FPF11, FP11-A and FP11-F, respectively). The DEC VAX 11/730, which used eight AM2901s for the CPU. Hewlett-Packard 1000 A-series model A600 used four AM2901 ALUs for its 16-bit processor The Xerox Dandelion, the machine used in the Xerox Star and Xerox 1108 Lisp machine. Several models of the GEC 4000 series minicomputers: 4060, 4150, 4160 (four Am2901 each,