Hello there,
Advanced High-performance Bus (AHB)
AHB is a bus protocol introduced in Advanced Microcontroller Bus Architecture version 2 published by ARM Ltd company.
it has the following features:
1.single edge clock protocol
2.split transactions
3.several bus masters
4.burst transfers
5.pipelined operations
6.single-cycle bus master handover
7.non-tristate implementation
8.large bus-widths (64/128 bit).
example: DMA,USB,ETHERNET,etc
Advanced Peripheral Bus (APB)
APB is designed for low bandwidth control accesses, for example register interfaces on system peripherals. This bus has an address and data phase similar to AHB, but a much reduced, low complexity signal list (for example no bursts). It has to support 32bit and 66 MHz signals.
Example : SPI, I2C,Timer,UART,ADC,etc