Definition of ACCESS.bus

ACCESS.bus, or A.b, is a digital communication protocol primarily used to connect low-bandwidth devices, like keyboards, mice, and other peripherals, to a central system. It was developed in the 1990s by Philips Semiconductors and is based on the I²C (Inter-Integrated Circuit) serial bus system. ACCESS.bus allows multiple devices to be connected to a single bus, simplifying wiring and reducing overall system complexity.


The phonetic pronunciation of the keyword “ACCESS.bus” would be: /ˈæʌs/ or “ACK-sehs-buhs”

Key Takeaways

  1. ACCESS.bus is a low-cost, low-speed serial bus system designed for communication between computer peripherals.
  2. It enables a plug-and-play interface, allowing devices to be hot-swapped, and uses a single cable to interconnect multiple devices in a daisy-chained configuration.
  3. Although it was introduced in 1994, ACCESS.bus has largely been replaced by more advanced communication systems like USB, but remains a viable option for simpler peripheral integration in niche applications.

Importance of ACCESS.bus

ACCESS.bus, or A.b, is a significant technology term because it refers to an innovative, low-cost, and low-power serial communication protocol that improves expandability and interoperability among a variety of devices.

Developed by Philips in the early 1990s, ACCESS.bus facilitates simplified connections and data transfers between multiple devices such as keyboards, mice, modems, and other peripherals.

It streamlines the management of numerous devices, reducing the need for multiple cables and managing multifarious connections.

Furthermore, the advanced capabilities of ACCESS.bus enable improved system configuration, diagnostics, and control, making it an essential milestone in the evolution of computer peripherals and communication technologies.


ACCESS.bus, also known as A.b, is a communication protocol that facilitates the connection and interaction between low-bandwidth devices such as keyboards, mice, and other peripherals, and a computer system. The primary purpose of ACCESS.bus technology is to allow various peripheral devices to communicate with a computer system in an efficient, cost-effective, and organized manner. Its plug-and-play functionality enables users to connect or disconnect devices without having to restart the computer.

Developed by Philips and DEC in the early 1990s, ACCESS.bus aimed to streamline device management and minimize cable clutter by allowing multiple devices to be connected to a single port, thus reducing the need for individual connectors. The implementation of ACCESS.bus technology is advantageous for users who require flexibility and ease of use when interacting with their computer systems. The A.b protocol adapts the I²C (Inter-Integrated Circuit) serial bus system, ensuring efficient data transfer and reducing the possibility of data loss or miscommunication.

This makes it ideal for home and office environments, where several peripheral devices are present and are regularly connected or disconnected. Moreover, its inherent ability to support hot-swapping (connecting/disconnecting devices while the system is running) further enhances the user experience. Although ACCESS.bus technology has been largely replaced by newer connection interfaces such as USB and Bluetooth in recent years, it remains a notable innovation that paved the way for more advanced and versatile device management solutions.

Examples of ACCESS.bus

ACCESS.bus (Advanced Configuration, Control, and Energy Saving System bus) is an electronic bus protocol that facilitates two-way communication between simpler devices and microcontrollers. Here are three real-world examples of its application:

Peripheral Devices: ACCESS.bus technology can be found in peripheral devices like keyboards, mice, and other input devices as it allows for seamless communication with the host system. It simplifies device connectivity and management by standardizing the interface and protocols for digital communication, thus reducing complexity and support costs.

Industrial Controls: In industrial settings, ACCESS.bus can be utilized in devices and systems for data acquisition and control. It allows microcontrollers to communicate with plant machinery and sensors like temperature sensors or production line devices efficiently and effectively, making it easier to monitor and control the operation of these machines.

Energy Management Systems: ACCESS.bus has found its application in commercial energy management systems, where it helps coordinate and control energy-consuming devices like HVAC and lighting. It allows system administrators to monitor, control, and manage energy usage in real-time, ultimately leading to reduced operational costs and a more energy-efficient building.Overall, ACCESS.bus technology helps simplify digital communication and control in various applications, ranging from standard computer peripherals to industrial control systems and energy-efficient building systems.


What is ACCESS.bus?

ACCESS.bus is a communication protocol created by Philips for easy communication between different types of electronic devices. It is designed to be user-friendly, cost-effective, and versatile. The benefits of ACCESS.bus include flexible data exchange and the ability to support various electronic devices and peripherals.

How does ACCESS.bus work?

ACCESS.bus uses a master-slave communication model, in which the “master” device initiates communication and sends commands to the “slave” devices, which respond accordingly. This communication occurs through a two-wire serial bus, with data exchange happening at a speed of up to 100 kbps.

Which devices can use ACCESS.bus?

ACCESS.bus can be used with various electronic devices, including computers, peripherals, and consumer electronics. Some examples of devices that can be connected using ACCESS.bus include keyboards, mice, monitors, printers, and digital cameras.

What are the advantages of using ACCESS.bus?

ACCESS.bus offers several advantages, such as easy integration with different types of electronic devices, flexible data exchange, and cost-effective implementation. It is also very user-friendly and can automatically detect and configure peripherals when they are connected to the system.

Is ACCESS.bus still widely used?

While ACCESS.bus was once popular due to its versatility and ease of use, it has been largely replaced by more modern communication protocols, such as USB and I2C. However, some legacy devices may still use ACCESS.bus for communication.

Related Technology Terms

  • ACCESS.bus protocol
  • ACCESS.bus devices
  • Device communication
  • Peripheral connection
  • Plug and play

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