Editing Commodore 128 (section)

== Specifications ==

* CPUs:<ref>{{cite magazine|title=The Commodore 128 Personal Computer System |magazine=[[Byte (magazine)|BYTE]]|publisher=[[McGraw-Hill]]|last=Wiese |first=William Jr|date=July 1986|quote=C-128 CP/M uses both the Z80 and 8502 processors. The Z80 executes most of the CP/M BIOS functions.|pages=269–278 |url=https://archive.org/details/eu_BYTE-1986-07_OCR/page/n278/mode/1up |volume=11 |issue=7 }}</ref>
** [[MOS Technology 8502]] @ 2 [[megahertz|MHz]] (1&nbsp;MHz selectable for C64 compatibility mode or C128's 40-column mode)
** [[Zilog Z80]]&nbsp;&nbsp;@ 4&nbsp;MHz (running at an effective 2&nbsp;MHz because of [[wait state]]s to allow the VIC-II video chip access to the system bus)
** (C128D(CR)): [[MOS Technology 6502]] for the integrated floppy controller
* MMU: MOS Technology 8722 Memory Management Unit controls 8502/Z80 processor selection; ROM/RAM banking; common RAM areas; relocation of zero page and stack
* RAM: 128 KB system RAM, 2&nbsp;KB 4-bit dedicated color RAM (for the VIC-II E), 16&nbsp;KB or 64&nbsp;KB dedicated video RAM (for the VDC), up to 512&nbsp;KB REU expansion RAM
* ROM: 72 KB
** 28 KB [[Commodore BASIC|BASIC 7.0]]
** 4 KB [[machine code monitor|MLM machine code monitor]]
** 8 KB C128 [[KERNAL]]
** 4 KB screen editor
** 4 KB Z80 [[BIOS]]
** 16 KB C64 ROM: ≈9&nbsp;KB C64 BASIC 2.0 + ≈7&nbsp;KB C64 KERNAL
** 4 KB C64 (or international) [[PETSCII|character generator]]
** 4 KB C128 (or national) character generator
** 32 KB Internal Function ROM (optional: for placement in motherboard socket)
** 32 KB External Function ROM (optional: for placement in REU socket)
* Video:
** [[MOS Technology VIC-II|MOS 8564/8566 VIC-II E]] (NTSC/PAL) for 40-column [[composite video]] (a [[television set|TV set]] can be used instead of a monitor if desired)
*** Direct register access through memory-mapped I/O
*** Text mode: 40×25, 16 colors
*** Graphics modes: 160×200, 320×200
*** 8 hardware sprites
*** 2 KB dedicated 4-bit color RAM, otherwise uses main memory as video RAM
** [[MOS Technology 8563|MOS 8563 VDC]] (or, in C128DCR, the [[MOS Technology 8568|8568]]) for 80-column digital [[RGB]]I component video, compatible with [[IBM Personal Computer|IBM PC]] [[Color Graphics Adapter|CGA]] monitors, monochrome display also possible on composite video monitors; usable with TV sets only when the set has [[SCART]] and/or baseband video-in sockets in addition to the antenna connector. Color is possible through SCART, only monochrome through baseband video-in.
*** Indirect register access (address register, data register in mapped memory)
*** Text mode: Fully programmable, typically 80×25 or 80x50, 16&nbsp;RGBI colors (not the same palette as the VIC-II)
*** Graphics modes: Fully programmable, typical modes are 320x200, 640×200, and 640×400 (interlaced).
*** 16 KB dedicated video RAM (64&nbsp;KB standard in C128DCR, C128/C128D can be upgraded to 64&nbsp;KB), accessible to the CPU only in a doubly indirect method (address register, data register on VDC, which in turn are addressed through address register, data register in mapped memory)
*** Limited [[blitter]] functionality
* Sound:
** [[MOS Technology SID|MOS 6581 SID]] (or, in the C128DCR, the [[MOS Technology SID|MOS 8580 SID]]) synthesizer chip
*** 3 [[Electronic oscillator|voices]], [[Envelope (music)#ADSR|ADSR]]-controllable
*** Standard SID waveforms ([[Triangle wave|triangle]], [[Sawtooth wave|sawtooth]], variable [[Square wave (waveform)|pulse]], [[white noise|noise]], and certain combined modes)
*** Multi-mode [[Audio filter|filter]]
*** 3 [[Ring modulation|ring modulators]]
* I/O ports:
** All [[Commodore 64#Specifications|Commodore 64 ports]] with 100 percent compatibility, plus the following:
** Higher "burst mode" speed possible on the serial bus
** Expansion port more flexibly programmable
** RGBI video output ([[D-subminiature|DE9]]-connector) logically similar to the [[IBM Personal Computer|IBM PC]] [[Color Graphics Adapter|CGA]] connector, but with an added [[monochrome]] composite signal. This added signal causes a minor incompatibility with certain CGA monitors that can be rectified by removing pin 7 from the plug at one end of the connecting cable.
** External keyboard input ([[D-subminiature|DB25]]-connector) (C128D(CR) only)