The APB is part of the AMBA 3 protocol family. It provides a low-cost interface that is optimized for minimal power consumption and reduced interface complexity. The APB interfaces to any peripherals that are low-bandwidth and do not require the high performance of a pipelined bus interface. The APB has unpipelined protocol. All signal transitions are only related to the rising edge of the clock to enable the integration of APB peripherals easily into any design flow. Every transfer takes at least two cycles.

The APB can interface with the AMBA Advanced High-performance Bus Lite (AHB-Lite) and AMBA Advanced Extensible Interface (AXI). You can use it to provide access to the programmable control registers of peripheral devices.-The APB is part of the AMBA 3 protocol family. It provides a low-cost interface that is optimized for minimal power consumption and reduced interface complexity. The APB interfaces to any peripherals that are low-bandwidth and do not require the high performance of a pipelined bus interface. The APB has unpipelined protocol. All signal transitions are only related to the rising edge of the clock to enable the integration of APB peripherals easily into any design flow. Every transfer takes at least two cycles.

The APB can interface with the AMBA Advanced High-performance Bus Lite　(AHB-Lite)　and AMBA Advanced Extensible Interface (AXI). You can use it to provide access to the programmable control registers of peripheral devices.