1971

The first single chip CPU was the Intel 4004, a 4-bit processor meant for a calculator. It processed data in 4 bits, but its instructions were 8 bits long. Program and data memory were separate, 1K of data memory and a 4K of program memory (in the form of a 4 level stack, used for CALL and RET instructions). There were also sixteen 4-bit general purpose registers The processor' speed is 60.000 opearations per second.

The 4004 consists of 2,300 transistors and has a 10mm² area.The microprocessor has 46 instructions. The 4040 is an enhanced version of the 4004, adding 14 instructions, larger stack (8 levels) and 8K program space. The sales price will be USD 200 per piece.

Robert Noyce invents the MICRO PROCESSOR. A Microprocessor is the hart of a computer. It is the active brain. When combined with memory, in and output ports than it becomes a complete computer.