ALU ORGANISATION
An ALU performs simple arithmetic and logic operation as well as shift operations. Complexity of an ALU relies on the type of instruction set for that it has been realized for. Simple ALUs can be designed for fixed-point numbers. Whereas the floating-point arithmetic implementation needs more complex control logic and data processing capabilities which implies that the hardware. Numerous micro-processor families use only fixed-point arithmetic capabilities in ALUs. For floating point arithmetic or other type of complex functions they might utilize an auxiliary special purpose unit. This unit is known as arithmetic co-processor.