System Specification for C65
March 1, 1991
CPU -- Commodore CSG4510 running at 1.02 or 3.5 Mhz
New instructions, including Rockwell and GTE extensions
Memory Mapper supporting up to 1 Megabyte address space
R6511-type UART (3-wire RS-232) device, programmable baud rate (50-56K baud, MIDI-capable), parity, word size, sync and async. modes. XD/RD wire ORed/ANDed with user port.
Two CSG6526-type CIA devices, each with 2 I/O ports, programmable TOD clocks, interval timers, interrupt control
RAM-- 128K bytes (DRAM)
Externally expandable from additional 512K bytes to 4MB using dedicated RAM expansion port.
ROM -- 128K bytes
C64 Kernel and BASIC 2.2
C65 Kernel, Editor, BASIC 10.0, ML Monitor (like C128)
DOS v10- (1581 subset)
Multiple character sets: 40 and 80 column versions
National keyboards/charsets for foreign language systems
Externally expandable by conventional C64 ROM cartridges via cartridge/expansion port using C64 decodes.
Externally expandable by additional 128K bytes or more via cartridge/expansion port using new system decodes.
DMA -- Custom DMAgic controller chip built-in
Absolute address access to entire 81-M system map, including 1/0 devices, both ROM & RAM expansion ports.
List-based DMA structures, can be chained together
Copy (up,down,invert), Fill, Swap, Mix(boolean Minterms) Hold, Modulus (window), Interrupt, and Resume modes
Block operations from 1 byte to 64K bytes
DRQ handshaking for I/O devices
Built-in support for (optional) expansion RAM controller
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Last updated May 23, 2002.