Abstract: The Advanced Microcontroller Bus Architeture (AMBA) is a widely used interconnection standard for System on Chip (SoC) design. An AMBA-based microcontroller typically consists of a high-performance system backbone bus (AMBA AHB or AMBA ASB), able to sustain the external memory bandwidth, on which the CPU, on-chip memory and other Direct Memory Access (DMA) devices reside. This bus provides a high-bandwidth interface between the elements that are involved in the majority of transfers. This paper present three distinct buses and their comparison. By considering merits of APB , AMBA can be design by using HDL.