The most interesting one for Another World is of course the 9h 320x200 16 colors. If at first Tandy "embraced" IBM's graphic sub-system, better sales enabled them to "improve" and ultimately "extinguish" the PCjr name.Įach version of the MDA/CGA/EGA/VGA was backward compatible but the TGA has three exclusive modes named 8h, 9h, and Ah. Later that year, Tandy Corporation released the "Tandy 1000" at a lower cost with easier expandability, and wider PC compatibility. When the big iron company released its 1984 "PCjr" aimed at the Apple II/Commodore 64 market they took the opportunity to improve on their aging CGA. Surprisingly, the graphics mode labeled TGA were not introduced by Tandy Corporation but by IBM. As we will see this is not quite what ended up being used. Notice the three 320x200 modes with at least 16 colors which match Another World VM requirements. Mode Type Resolution Colors RAM/VRAM Mapping VRAM (KiB) At the time, depending on the graphic card, 19 modes were available. Thankfully the PC BIOS provided a routine to configure everything. The latest VGA generation used a much more impressive 6-bit channel (18 bits/pixel) system.Ĭonfiguring these cards was a mess of 300 registers all interacting together. The older generations TGA/EGA used an abysmal 2-bit channel (6 bits/color) color system. MDA and CGA were mostly extinct but there was still a large base of old TGA/EGA which had not upgraded yet to VGA. The US$36 IBM PC Technical Reference Manual included complete circuit schematics, commented ROM BIOS source code, and other engineering and programming information for all of IBM's PC-related hardware, plus instructions on designing third-party peripherals.įrom the first PC in 1981 to 1991, five major graphic standard were released. For consumers used to wrestle with manufacturers for technical details, it was a whole new world. They took the approach even further by making available specs and schematics of the machine. They purchased elements such as the CPU from Intel and shipped with a PC DOS 1.0 operating system from Microsoft. Instead of proceeding vertically as they had done by the past, with most components and software developed in-house, IBM built its micro-computer horizontally. With several competitors such as Hewlett-Packard (HP), Texas Instruments (TI), Tandy, and Data General already established, IBM did things differently in order to stand out. When 1979 saw sales of micro-computers reach $150 million, the "Colossus of Armonk" decided to release one of its own. For three decades, IBM had been comfortable dominating the mainframe market.
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