Orao Emulator

Introduction

This is an Orao emulator for the SAM Coupé. It emulates the Croatian Eagle home computer, a 6502-based machine developed by PEL Varaždin and released in 1985.

It’s really a proof-of-concept project rather than a practical emulator, though it does provide a surprisingly complete emulation considering the running platform:

• Full 65C02 emulation.
• Scaled or pan-and-scan 256x192 view of original 256x256 display.
• 1-bit DAC sound output.
• Full keyboard input.

Running speed is around 1/8^th that of the original machine, but also dependent on how much is being written to the display. The animated images below show the running speed on a normal SAM (6MHz Z80B).

Using the Quazar Mayhem accelerator board (at 20MHz) gives up to 75% original speed. As well as the increase in processor speed, it benefits from reduced memory contention and the emulation’s heavy register use. Games are finally playable!

Many thanks to Josip Perušanec, whose Orao emulator source code was an invaluable reference. Thanks also to Tomaz Kac for providing additional information.

Download

Version 1.2, last updated 5th September 2008.

Orao Emulator (79K)
Source Code (GitHub)

Controls

In SimCoupe, use Ctrl for the Symbol key modifier.

Screenshots