Individual Computers Catweasel

The Catweasel is a family of enhanced floppy drive controllers from German company Individual Computers. These controllers are designed to allow more recent computers, such as PCs, to access a wide variety of older disk formats using standard floppy drives.

The initial version of the Catweasel was introduced circa 1996 and has since undergone several revisions. The Catweasel MK2, for the Commodore Amiga 1200 and Amiga 4000, sold out in October 2001. The MK3 added PC compatibility, sold more units than the MK2, and sold out in mid-2004. It was succeeded by the MK4.

Because of widespread shortage (due to low production volumes) and relatively high demand, older versions of the Catweasel can accrue high prices when sold privately; for instance on the Internet auction site eBay.

Catweasel MK3

The Catweasel MK3 was designed with the goal of maximum compatibility, and would interface with either a PCI slot, an Amiga Zorro II slot or the clock-port of an Amiga 1200. In addition to the low-level access granted to floppy drives, it has a socket for a Commodore 64 SID sound chip, a port for an Amiga 2000 keyboard, and two 9-pin digital joysticks (Atari 2600 de facto standard).

The SID chip socket allows Catweasel users to play SID chiptunes on the real chip instead of relying on software emulation for original sounding SID playback. The WinVICE emulator supports the Catweasel's SID features starting with version 1.13.

As of September 2004, software support for major operating systems such as Windows and Linux was limited, although new drivers and hardware were under development (see below). The most promising development for the floppy controller portion was reported to be a modular software product for Windows called Arjuna, the first public version of which was announced on 8 February 2004.

Catweasel MK4

The Catweasel MK4 was officially announced on 18 July 2004, with a wide array of new features planned. However, due to manufacturing delays and production backlogs, the MK4 was not released until early February 2005.

The latest versions of the Catweasel make heavy use of reconfigurable logic in the form of FPGA chips. On the MK4, software drivers may update the hardware directly so that e.g. unsupported disk formats at the time of shipping can be added simply by downloading the new setup code through the Internet and then reprogramming the hardware core with the Catweasel still sitting in the host computer.

The Catweasel MK4 has drivers for Linux, Windows 98SE/ME/2000/XP, and Amiga OS 4; additionally, the intention is to support Mac OS X at a later date.

External links

• Catweasel product webpage, Catweasel MK4 announcement
• Arjuna floppy controller software homepage,
• Catweasel Floppy Read/Write Tools for TRS-80 & DEC RX-02 diskettes
• ACID 64 Player - C64 Music Player for all HardSID cards and the Catweasel MK series
• Linux kernel driver and command-line utility