THE MCS-4 - An LSI micro computer system [reprint]

The MCS-4 is a totally self-contained four-bit general purpose microprogrammable computer in component form. It consists of four basic elements: the CPU (central proces sing unit), the ROM (read only memory), the RAM (random access memory), and the SR (shift register). They are fabricated by MOS silicon gate technology and packaged in economical sixteen pin DIPs to minimize board area and reduce system cost. Using combinations of these standard building blocks, any degree of customization may be built into these powerful microprogrammed fourbit computers. Using as few as two devices, a C,PU and a ROM, a four-bit microprogrammed dedicated computer may be built for under $50. This paper describes this new micro-computer set, highlighting the system partitioning and the basic CPU hardware instruction set.