The AHB and APB are advanced buses designed for different purposes. The AHB is a high-performance bus meant for transferring large amounts of data quickly, while the APB is a peripheral bus meant for connecting low-bandwidth devices to the system. Despite their differences, the two buses share some similarities, which this article will explore.
What is AHB?
AHB is short for Advanced High-performance Bus. AHB was developed by DEC, Intel, and Motorola as a point-to-point bus protocol that supports multiplexing, burst transfers, and split transactions. AHB provides a high-bandwidth path between the processor and peripheral devices.
AHB also includes error detection and correction mechanism to ensure data integrity. AHB is used in many embedded systems and is well suited for applications that require high bandwidth or real-time data transfer. AHB has been widely adopted in the industry and is used in many processors and chipsets.
What is APB?
APB computer bus is a synchronous bus used in computer systems. APB stands for Advanced Peripheral Bus. APB was first used in 1985 by Intel Corporation. APB was later co-developed by Motorola and Intel. APB is a low-speed bus used to connect low-bandwidth devices to the system’s memory and CPU.
APB devices are connected to the APB bus through an APB bridge. The APB bus is not plug-and-play compatible with the PCI bus. APB uses a different signaling method than PCI, which limits its speed. APB has a maximum transfer rate of 10 megabits per second.
Difference between AHB and APB
- AHB and APB are two different types of computer buses used to connect various devices to the CPU. AHB is an advanced high-performance bus that provides high-speed data transfer between devices. AHB can be used to connect devices such as RAM, ROM, and I/O devices. AHB is a point-to-point bus, which means that each device is directly connected to the CPU.
- APB is an advanced peripheral bus that connects low-speed peripherals to the CPU. APB is a multi-drop bus, which means that all devices share a common bus. AHB has a lower pin count than APB, which makes it more scalable. AHB also supports multiple masters, while APB only supports one master.
- AHB is faster than APB, but it uses more power. AHB is not compatible with 5V devices, while APB is compatible with both 3.3V and 5V devices. AHB uses a burst mode of data transfer, while APB uses a single data transfer. AHB requires a separate address and data bus, while APB uses a single bus for both address and data transfer.
The AHB Advanced High-performance Bus and the APB Advanced Peripheral Bus are both designed for different purposes. The AHB bus is intended for high-performance systems while the APB bus is aimed at peripheral devices. When deciding which bus to use, it’s important to consider what system you are building and what functions need to be performed.