Commodore One Twenty Eight

COMMODORE 128 / 128D

My first & beloved computer :) (by Hayrettin YILDIZ)

All information below come from my fond memories.

OPERATING MODES:

  1) C64 Compatibility Mode
        64K RAM, Basic 2.0, 40 column text
        MOS 8502 CPU operated at 1 MHz
  2) C128 Native Mode
        128K RAM, Basic 7.0, 40 or 80 column text
        MOS 8502 CPU operated at 1 or 2MHz
  3) CP/M Plus (3.0) Mode
        128K RAM, CP/M 3.0, 40 or 80 column text
        Zilog Z80A CPU operated at 1 MHz

CPU:

  Two microprocessors included:
  1) MOS 8502 (6502/6510 derivative)
        Operates at 1 or 2 MHz
        Both C64 and C128 modes uses this CPU
  2) Zilog Z80A
        Operates at 2 MHz
        CP/M Plus (3.0) mode uses this CPU
        Boots up the system

MEMORY:

  1) ROM:
        C64 Basic 2.0 ROM    8K
        C64 Kernal ROM       8K
        C64 Character ROM    4K
        C128 Basic 7.0 ROM  32K
  2) RAM:
        128K (2x64K RAM Banks)
        Expandable up to 1MB (16 RAM Banks)
  3) I/O:
        4K memory mapped I/O area interfaced to I/O chips (SID, VIC, CIAs etc)
        1K Color Memory (for VIC chip modes)

MMU:

    Controls up to 16 banks of 64K memory blocks
    With bank switching 1024K of total memory possible

SOUND:

    SID 8581 (6581 derivative)
    Analog sound processor
    3 independent sound voices
    3 waveform (triangle, sawtooth, pulse) and a white noise
    16 bit frequency resolution
    Approximately 8 octave sound pitch range
    ADSR volume envelopes
    4 bit master volume register
    Voice modulation and filtering
    Reads potentiometer inputs (eg. paddles) from joystick ports
    Random number generator

VIDEO:

  Two different & independent video chips included
  Both can operate simultaneously with two video outputs (one composite vide, one RGB)
  1) VIC 8567 (Video Interface Chip)
       VIC II (6567/9) derivative
       Runs only at slow (1 MHz) mode
       16 colors
       Composite Video & TV (RF) Output Signals
       16K RAM mapped from main RAM (selectable 16K VRAM bank)
       Horizontal and vertical pixel based smooth scrolling (up to 7 pixels)
       Interrupt creation
          Sprite collisions
          Raster line compare
          Light gun latch
       40x25 characters text mode
          Singlecolor mode: 8x8 pixel character resolution 
          Multicolor mode : 4x8 pixel character resolution 
          Each character set contains 256 character definitions (total 2K)
       320x200 pixel hi-res graphics mode
          Each 8x8 pixel block can have different fore and background color
       160x200 pixel lo-res multicolor graphics mode
          Each 4x8 pixel block can have 3 different colors and one fixed background color
       8 MOBs (Movable Object Blocks, Sprites) per rasterline
          In hi-res single color mode: 24x21 pixel resolution
          In lo-res multi-color mode: 12x21 pixel resolution
          Collision detection with other sprites and background is possible
          Sprite-sprite (number based) and sprite-background priority is selectable

  2) VDC 8564 (Video Display Controller):
       Runs at slow (1 MHz) and fast (2 MHz) modes
       RGBI Video Output
       Separate video memory (16K or 64K) accessible from 2 byte memory interface
       80x25 characters text mode (16 colors & attributes)
       640x200 regular graphics resolution
       640x400 interlaced resolution
       Programmable resolutions (up to 720x512) & colour depths (up to 16 colors)

INPUT/OUTPUT:

   Two CIA 8526 I/O chips included (Complex Interface Adapter)
   CIA 6526 derivatives (compatible)
   Keyboard, joystick, serial port handling
   Time of Day (TOD) clocks, precise time counters
   External Connectors:
      1 Expansion port
      1 User port
      1 Serial port (up to 5 devices)
      2 Joystick ports (9 pin)
      1 RF port (TV Output, VIC chip)
      1 Composite Video Output (VIC chip)
      1 RGBI Video Output (VDC chip)