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
   1. K RAM, Basic 2.0, 40 column text

MOS 8502 CPU operated at 1 MHz


1. ) C128 Native Mode
   1. K RAM, Basic 7.0, 40 or 80 column text

MOS 8502 CPU operated at 1 or 2MHz


1. ) CP/M Plus (3.0) Mode
   1. K 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


1. ) 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


1. ) RAM:
   1. K (2x64K RAM Banks)

Expandable up to 1MB (16 RAM Banks)


1. ) I/O:
   1. K memory mapped I/O area interfaced to I/O chips (SID, VIC, CIAs etc)
   2. K 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


1. independent sound voices
2. waveform (triangle, sawtooth, pulse) and a white noise
3. bit frequency resolution

Approximately 8 octave sound pitch range
ADSR volume envelopes


1. 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


1. colors

Composite Video & TV (RF) Output Signals


1. K 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


1. x25 characters text mode

Singlecolor mode: 8x8 pixel character resolution
Multicolor mode : 4x8 pixel character resolution
Each character set contains 256 character definitions (total 2K)


1. x200 pixel hi-res graphics mode

Each 8x8 pixel block can have different fore and background color


1. x200 pixel lo-res multicolor graphics mode

Each 4x8 pixel block can have 3 different colors and one fixed background color


1. 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


1. ) 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


1. x25 characters text mode (16 colors & attributes)
2. x200 regular graphics resolution
3. x400 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
2. User port
3. Serial port (up to 5 devices)
4. Joystick ports (9 pin)
5. RF port (TV Output, VIC chip)
6. Composite Video Output (VIC chip)
7. RGBI Video Output (VDC chip)