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Amiga Ranger is an unreleased prototype personal computer by Commodore which was intended to be the second generation Amiga chipset, prior to ECS. It was designed by the original Los Gatos Amiga team including Jay Miner. ==Overview== After the release of the Amiga 1000, Jay Miner began to design its intended successor, between 1986 and 1987. Code named Amiga Ranger, it was planned to be highly expandable like Amiga 2000 with better graphics and CPU. The Ranger is said to have possibly included a 68010 or 68020 CPU. Information for this new chipset remains unclear. However, the sound system may have still been the same as the original chipset. According to R. J. Mical, the new chipset kept the original 13 bit DAC for its CLUT but with quadrupled color registers from 32 to 128. The color palette would have remained at 4096 colors but the resolution could go up to 1024×1024 pixels with 128 colors (7 bit color depth). Additionally the chipset can address up to of Chip RAM space. Ranger used 2MB VRAM as chip memory. In an interview, Jay Miner described benefits of using VRAM instead of DRAM; this gave the display system enough memory bandwidth for 1024×1024 pixel displays. From the known specification, it could be said that Ranger chipset was designed to compete with Sharp's X68000 personal computers (released in 1987) which takes advantage of VRAM technology for displaying a 1024×1024 pixel screens in 16 colors. Jay Miner made sure that the Ranger chipset was completed and fully tested before he left Commodore in hope that one day the company would release it. But at that time, VRAM was considered expensive compared to DRAM, so Commodore refused to release Ranger for its high price which was unsuitable for the low-end systems like Amiga 500 to cover its costs. Dale Luck is in possession of a Ranger system prototype, but it's unknown in what state it is. In a few years, VRAM costs dropped to be only 20% more than DRAM, so Commodore planned to use VRAM in the AAA chipset, the next-gen Amiga chipset left in an unfinished state when the company went into voluntary liquidation in 1994. Some thoughts of a built-in blitter per playfield designed in Ranger had been rejected by Dave Haynie. However, a post on Team Amiga explained the Ranger idea: 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Amiga Ranger Chipset」の詳細全文を読む スポンサード リンク
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