<
computer> (Or
Commodore 64DX, C65, C64DX) The last 8-bit
computer designed by
Commodore Business Machines, about
1989-1991. The C65 boasts an
ugly collection of
custom
integrated circuits which makes even the
Amiga hardware
look standard.
The core of the C65
chipset is the
CSG 4510 and {CSG
4569}. The 4510 is a
65CE02 with two
6526 CIAs. The
4569 is equivalent to a combination of the
6569 VIC-II and
the
MMU of the
Commodore 64. The C65 also has a {DMA
controller} (Commodore's purpose built
DMAgic) which also
functions as a simple
blitter, and a
floppy controller for
the internal
Commodore 1581-like disk drive. The floppy
controller, known as the
F011, supports seven drives (though
the
DOS only supports 2). The
4510 supports all the
C64
video modes, plus an 80 column text mode, and
bitplane
modes. The bitplane modes can use up to eight bitplanes, and
resolutions of up to 1280 x 400. The
palette is 12-bit
like 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
RAM
on each. The VIC-III can access the D-bus while the CPU
accesses the E-bus, and then they can swap around. This
effectively makes the whole 8MB
address space both {chip
ram} and
fast ram.
RAM expansion is accomplished through
a
trap door slot in the bottom which uses a
grock of a
connector. The C65 has a
C128-like native mode, where all
of the new features are enabled, and the CPU runs at 3.5
megahertz with its
pipeline enabled. It also has a C64
incompatibility mode which offers approx 50-80%
compatibility with C64 software by turning off all its {bells
and whistles}. The
bells and whistles can still be accessed
from the C64 mode, which is dissimilar to the C128's
inescapable C64 mode.
Production of the C65 was dropped only a few weeks before it
moved from the Alpha stage, possibly due to Commodore's cash
shortage.
Commodore estimate that "between 50 and 10000"
exist. There are at least three in Australia, about 30 in
Germany and "some" in the USA and Canada.
(1996-04-07)