IBM ThinkPad R52 Motherboard Schematic Circuit Diagram
IBM ThinkPad R52 Motherboard Schematic Circuit Diagram
What is Reverse Engineering in PC Software?
We try to know who controls PC software or who works behind the PC software in some of the early posts. In this post, we will know more about these.
The Compaq and Phoenix used to legally duplicate the IBM PC BIOS was an intelligent form of reverse engineering. This is known as a clean-room technique to reverse-engineering software, and it can protect you from legal action if done correctly. The clean-room method was not difficult to duplicate since IBM's original PC BIOS had a restricted but well-defined set of operations and were just 8,096 bytes long. It was pretty simple to keep up with any modifications IBM made to the IBM BIOS as it evolved. Even today, most motherboard BIOSs have only approximately 32KB– 128KB of active code after excluding the power-on self-test (POST) and BIOS Setup (used for system configuration) portions of the BIOS, and current OSs disregard much of it anyway by loading code and drivers from the disk. In essence, the current motherboard BIOS is simply used to set up the system and load the operating system. Although some PC manufacturers still build portions of their own BIOS code, the majority of PC makers now get their BIOS from a third-party developer. The primary BIOS software developers for PC systems and motherboard manufacturers are Phoenix Technologies and American Megatrends, Inc. (AMI). Phoenix Technologies owns Award Software, a third major provider of BIOS software, and continues to market Award BIOS-based devices. Insyde Software, a fourth major BIOS software producer, specialized in BIOS solutions for laptops and mobile devices.
