next up previous contents
Next: 2 Frequently asked questions Up: SIDPLAY Home Page Previous: Contents

1 Introduction

1.1 What is SIDPLAY

Basically, SIDPLAY is just an ordinary music player software. More specifically, SIDPLAY emulates the Sound Interface Device chip (MOS 6581, commonly called SID) and the Micro Processor Unit (MOS 6510) of the Commodore 64 on your computer. It is a platform independent software emulating these hardware components. Therefore it is able to load and execute C64 machine code programs which produce music or sound. In general these are independent fragments of code and data which have been ripped from games and demonstration programs and have been transferred directly from the C64. All you need is a supported operating system and audio hardware with average PCM waveform playback capabilities. A fast CPU and a 16-bit sound card are recommended for better performance and quality.

SID emulation has its roots in the Amiga programs The 100 most remembered C64 game-tunes and PlaySID by Per Håkan Sundell and Ron Birk.

SIDPLAY itself is not based on any portions of sourcecode for PlaySID. It has been developed and programmed from scratch. As a result and also influenced by the different hardware that has been used during development, its SID emulator architecture differs significantly from PlaySID.

After PlaySID, SIDPLAY was the second publically available SID music player world-wide and the first one on multiple operating systems.

SIDPLAY is not related to the music editing and playing programs on the C64, called Sidplayer by Craig Chamberlain and Stereo Sidplayer by Mark Dickenson. In the early days of the SIDPLAY project I was not aware of the existence of those C64 programs. I didn't want to start any confusion by choosing a similar namegif. Nevertheless, minor support for Sidplayer .MUS files is implemented, too.

1.2 Disclaimer

Unlike some available C64 emulators SIDPLAY does not claim it would emulate the original SID chip perfectly, neither the MOS-6581 revisions nor the later MOS-8580 revisions. Better do not replay at frequencies much higher than 48 kHz.

The analogue output of the SID hardware is extremely complex and partially irregular. This makes it almost impossible for an emulator author to develop software that calculates equivalent output. Additionally, the output of each individual SID chip varies not just slightly due to tolerances in its electronical components, such as capacitors for instance. To give you an impression of the extent of a possible difference between two SID chips, it is possible that you are hardly able to notice a low-pass filter effect on one chip whereas the same filter effect sounds way too strong on another chip.

1.3 The term sidtune

Apparently, the European part of the world refers to any piece of Commodore 64 music - where the SID chip is used to produce sound - as sidtune, while some of the American part of the world only denote music, which is made with the C64 programs Sidplayer or Stereo Sidplayer, sidtunes or just sids.

In any SIDPLAY related document the term sidtune applies to any kind of SID music. This is an obvious decision, because almost all the music in well-known C64 games and demos was not made with either the two applications mentioned above, but each song is commonly called a sidtune. Especially it is not distinguished between ready-to-play files and music player machine code (and data) in a C64 program.

When a song is just playing through the SID chip this is called a sidtune, too. For instance, you can hear someone saying ``I'm listening to the Commando sidtune'' instead of ``I'm listening to Rob Hubbard's music from Commando''.

1.4 Sidtunes for SIDPLAY and compatibles

More than 7700 different sidtunes from Commodore 64 games and demos are available on the Internet. A lot even contain several sub-songs. These musics are still copyrighted by their original creators or by the company who owned the rights in the first release.

A lot of the sidtunes are 10 years old. Some are even older, some are not a month old. Hence, spreading them together with the original credits is more likely to act as advertising than causing any consequential damage. Additionally, the maintainers of recent sidtune collections are in contact with a lot of (famous) C64 music composers and get invaluable support upon verifying the song credits and ownerships.

See section 2.4 on where to get SID music.

1.5 License Agreement

NOTE TO DISTRIBUTORS OF FREEWARE, SHAREWARE,
PUBLIC DOMAIN SOFTWARE, CD-ROMS AND OTHER SIMILAR SOFTWARE

This license applies to any of the official versions of SIDPLAY unless explicitly stated otherwise by an official SIDPLAY author. Official versions are any releases of this software that have been distributed or linked from the SIDPLAY Home Page, respectively. Only official SIDPLAY authors are allowed to restrict or tighten up this license in either way.

Any official SIDPLAY software package does not need to include a copy of this license text. If any official version of SIDPLAY is distributed under the terms and conditions of a modified or different license, a copy of the license text has to be included.

This software including all enclosed files is protected by the German and international copyright laws.

You may not modify or alter parts or the entire software package or its contents.

You may not publish, transfer, or otherwise make available this software, in any form, to anyone without the prior written consent of the authors.

You are only free to use, copy and distribute this software for noncommercial use, if no fee is charged for copying, distribution, media (e.g. disks, streamer tapes, CD-ROMs ...), porto, package or electronic download services, and the software package including all original files remains unmodified or unchanged in any other way. It is also prohibited to give away this software as a free sample or promotion matter with commercial purposes.

However the authors are interested in the publication of this software by commercial (or private) distributors, e.g. by adding it to a Freeware collection or putting it on CD-ROMs. Certainly this requires a prior written permission from the author as already stated above.

Firms, companies and private distributors who like to aquire rights in the software or even exclusive rights in further programs are hereby asked to contact the authors.


next up previous contents
Next: 2 Frequently asked questions Up: SIDPLAY Home Page Previous: Contents