What is the significance of hardware abstraction layer?

Answer 1

H.A.L.----is a MICROSOFT-standardized,software-structured, interface for ALL and Any I/O devices to communicate their configuration particulars and interrupt sequences to & from a Windows Operating system;as well as any others that can make efficient use of the HARDWARE-ABSTRACTION-LAYER (H.A.L.) concept. Since all devices communicate to the same computer memory address RANGE---only the timing need be controlled----DEVICE IRQ and CPU micro-code (and clock speed!!!) to the rescue!!!! Because of these things and more,when a new device is added (let's say..)it can BROADCAST its needs to the operating systems' I/O interface--H.A.L.---thereby making PLUG-and-PLAY interfacing a "no-Brainer" as the next logical step!!!!!!!!!! ALSO:--Prevents direct access to RAM by hardware devices;preventing 2 or more devices from seeking the same address or address range by more than one IRQ at-a-time; which can cause questionable 'hangs' or "reasonless" fault(s) during operation. *-reasonless---ANY error NOT anticipated by hardware designers and/or device driver programmers---and is not stored in ROM,(most anticipated device errors ARE stored in a memory within the device)which then allows both a device and its hosting compter to recognize and report the condition to a human-interface-device such as a printer or terminal-screen. Together these functions,when efficiently orchestrated,make plug and play the beautiful thing we've come to know! THAT IS THE SIGNIFICANCE OF THE HARDWARE ABSTRACTION LAYER. (sRj)