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Daterad Rekreationell Övnings-Mikrodator

DRÖM ("DREAM" in Swedish) is an emulator for the CHIP-8-based DREAM 6800 home computer, powered by LÖVE and Moon6800.

You can read about the development of DRÖM in these blog posts, and about the DREAM's history on the official DREAM 6800 Archive Site.

Screenshot of CHIPOS in DRÖM

Features

  • Faithful emulation of the DREAM
  • 4K of RAM
  • Can quickload and play CHIP-8 games
  • Includes software:
    • Michael J. Bauer's original CHIPOS monitor program
    • Michael J. Bauer's DREAM INVADERS game
  • A comprehensive debug interface, powered by love-imgui
  • CRT shaders!

A very special thanks to Michael J. Bauer who permitted me to include the original software.

Memory map

Address range Contents
0000 - 03FF RAM
8010 - 8011 PIA A (keypad)
8012 - 8013 PIA B (speaker & cassette)
C000 - C3FF EPROM
C400 - FFFF Mirrored EPROM

CHIPOS

When CHIPOS starts up, it will display an address at the bottom of the screen.

First, type a 4-digit hexadecimal number to enter a memory address.

Then execute one of the following commands:

  • FN, 0: MEMOD (MEMory MODify): The contents of the address will be displayed as a 2-digit hexadecimal number. Type a new 2-digit number to replace the memory contents. The memory address will automatically advance by one. You can also press FN to advance one byte without modifying anyting.
  • FN, 3: Run: Executes a program starting at the current address. To run a CHIP-8 program (which is loaded at address 0200), run the CHIP-8 interpreter at C000.

Loading (FN, 1) and dumping (FN, 2) cassettes isn't supported yet, but instead you can use the "File" menu to quickload CHIP-8 games or DREAM INVADERS.

At any time, press RESET to return to the monitor program.

History

The DREAM 6800 (Domestic Recreational Educational and Adaptive Microcomputer) was a Motorola 6800-based microcomputer created by Michael J. Bauer. Its construction was detailed in Electronics Australia in 1979, and it included a monitor program called CHIPOS (Compact Hexadecimal Interpretive Programming and Operating System) and a CHIP-8 interpreter.

It had its own newsletter, DREAMER, published between 1980 and 1982.

You can read more about the DREAM's history on Michael's official DREAM 6800 Archive Site.