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(Or Commodore 64DX, C65, C64DX) The last 8-bitcomputer designed by Commodore Business Machines, about1989-1991. The C65 boasts an ugly collection of customintegrated circuits which makes even the Amiga hardwarelook standard.The core of the C65 chipset is the CSG 4510 and CSG4569. The 4510 is a 65CE02 with two 6526 CIAs. The4569 is equivalent to a combination of the 6569 VIC-II andthe MMU of the Commodore 64. The C65 also has a DMAcontroller (Commodore's purpose built DMAgic) which alsofunctions as a simple blitter, and a floppy controller forthe internal Commodore 1581-like disk drive. The floppycontroller, known as the F011, supports seven drives (thoughthe DOS only supports 2). The 4510 supports all the C64video modes, plus an 80 column text mode, and bitplanemodes. The bitplane modes can use up to eight bitplanes, andresolutions of up to 1280 x 400. The palette is 12-bitlike the Amiga 500. It also has two SID's (MOS 8580/6581)for stereo audio.The C65 has two busses, D and E, with 64 kilobytes of RAMon each. The VIC-III can access the D-bus while the CPUaccesses the E-bus, and then they can swap around. Thiseffectively makes the whole 8MB address space both chipram and fast ram. RAM expansion is accomplished througha trap door slot in the bottom which uses a grock of aconnector. The C65 has a C128-like native mode, where allof the new features are enabled, and the CPU runs at 3.5megahertz with its pipeline enabled. It also has a C64incompatibility mode which offers approx 50-80%compatibility with C64 software by turning off all its bellsand whistles. The bells and whistles can still be accessedfrom the C64 mode, which is dissimilar to the C128'sinescapable C64 mode.Production of the C65 was dropped only a few weeks before itmoved from the Alpha stage, possibly due to Commodore's cashshortage. Commodore estimate that "between 50 and 10000"exist. There are at least three in Australia, about 30 inGermany and "some" in the USA and Canada.