Commodore 64 disk / tape emulation

Some of the oldest adapters are the C64 user port to RS232 converters. Those were standardized and originally designed to connect printers and other 3rd party hardware, including modems. Later, those adapters have also been adopted for disk drive emulation and even Internet connections. However, the most widespread adapters were probably the different disk drive and printer plug C64 serial bus to Parallel port adapter that evolved for transferring data between disk drives and parallel port supplied computers. Because of hard timing requirements on the C64 side, those are unfortunately not applicable to laptops or multitasking operation systems. There also exist a more limited number of adapters for the C64 tape interface. While the data transfer over the user port is usually limited to 2.4 kbit/s, the C64 expansion port cartridge interface supports transfer rates of one to two magnitudes higher through proprietary protocols. There exist C64 expansion port adapters that support both hard disks, memory cards, USB-disks and Ethernet connections.

The software is typically open source, and so is most of the hardware designs. You can therefore build most of the hardware yourself, though they are usually also available from online shops.

Full emulation of the Commodore 1541 disk drive or Commodore 1530 datasette is required e.g. to support fast loaders. Software that supports the basic transfer protocols, such as load and save, will not support fast loaders.

Software exists that replaces the basic transfer protocols with proprietary alternatives. These protocols require special software on both the host side and the Commodore 64 side.

Some software supports transfer between a disk or tape drive and a computer other than a Commodore 64.

Tape connector adapters

• The C2N232 adapter is a RS-232 interface that can be plugged to the cassette port of an 8-bit Commodore computer and supports emulation of the tape deck. The C2N232 hardware was designed in 2001-2003 by Marko Mäkelä. It is freely available as open source, and a few hundred were built and sold.[17]
• The C64S tape adapter lets you connect your tape deck to a PC parallel port.[22]
• The Cassadapt tape adapter allows to convert tape programs (T64 and PRG) from a PC to either the Commodore 64 or a C2N tape deck.[23]

Disk connector adapters

• The 1541-III is a PIC microcontroller controlling a MMC/SD card with .D64 files. It does however NOT support fastloaders.[24]
• The 1541EMU cable hardware supports full emulation of the Commodore 1541 disk drive. The cable exists in type0 and type1 flavors with full and slightly reduced compatibility, respectively.[3] The 1541EMU hardware was designed in 2001-2002 by Ville Muikkula et al. for use with the 1541EMU software. The 1541EMU cable is available through both building instructions and shops.[25]
• The 1541U-I (and 1541U-II) emulates a 1541 disk drive for Commodore computers. It uses an SD-card or MMC-card to store virtual floppy disks. Disk content can be browsed through software on the cartridge and navigated through buttons on the device. The selected disk can be downloaded either through the fully compatible 1541 interface or through a faster but less compatible proprietary interface.[4]
• The X1541 cables allow (full emulation of? /) copying to and from the Commodore 1541 disk drive. The realtime requirements for emulating the 1541 disk drive are exceptionally hard, and a variety of cable flavors have been constructed to improve compatibility with multi-tasking systems and faster PCs than the Pentium to some degree.[26] For compatibility, check the documentation of each application, or confer the reference. The X1541 cable is available through both building instructions and shops.[25][27] The original X1541 cable was designed in 1992 by Leopoldo Ghielmetti for use with the X1541 software.
• The XP1541 cables are variants of the X1541 cables flavors, adding parallel support for faster transfer between PC and the C64 disk drive. The XP1541 cable was designed in 1997 by Joe Forster/STA.[28]
• The XU1541 adapter (beta) attaches a 1541 etc. disk drives to a PC using the USB connection, opening for easy transfer of disk images from and to the disk drive. The XU1541 is currently only recommended for people who are willing to cope with glitches and will perhaps even do some testing and bug hunting.[29]
• The ZoomFloppy connects your Commodore 1541/1571/1581 drives to a Windows, Mac, or Linux computer. This allows you to read and write files or entire disk images from the original media.[30] The ZoomFloppy uses the XUM1541 firmware by Nate Lawson, based on XU1541.[31] The PCB was manufactured by Jim Brain and can also be bought online.[32]

RS232 user port adapters

The User Port RS232 adapters provides a low-speed serial port for Commodore 8-bit computers, originally for connecting printers etc. They can operate at speeds of up to 2.4 kbit/s.

• The Comet64 Internet Modem is a Serial-to-Ethernet (S2E) device. This modem connects to the user port and provides an Internet connection. Also available with RS232 output.[33]
• The EZ-232 RS232 Serial Interface provides a low-speed serial port for Commodore 8-bit computers. It can operate at speeds of up to 2400 bit/s, when configured as a standard interface, and at speeds of up to 9600 bit/s, when configured as a UP9600 interface. The EZ-232 RS232 Serial Interface was designed by Jim Brain.[34]
• The Handic V24 is a RS-232 converter for Commodore machines.
• The VIC-1011A RS232C is a RS-232 converter for Commodore machines.

Proprietary user port adapters

• The PC64 cable was designed in 1994 by Wolfgang Lorenz.[35]
• The Power-Loader cable is a companion for the X1541 cables flavors, adding parallel support for faster transfer between PC and the C64. The Power-Loader (Pwr/XE) cable was developed by Nicholas Coplin, for use with 64HDDsoftware.[36]
• The Prlink is a cable designed for the Prlink software by Marko Mäkelä and Olaf Seibert.

RS232 expansion port adapters

Expansion port cartridges provides a high-speed connection to an external computer and/or the Internet. The output interface is a RS232 interface for connecting to an external computer. Internet connection can be obtained through the external computer or via a series to Internet adapter.[37] Some adapters also have separate Ethernet interface for connecting to Internet. The most common cartridges for external connection is listed below.[38]

• The RR Net is an add on to the Retro-Replay cartridge that allows for broadband Internet access.
• The Silver Surfer add on to the Retro-Replay cartridge provides RS232 capabilities. It provides a transfer rate probably similar to that of Turbo232, limited to 57.8 kbit/s for most software.[39] Silver Surfer is available from an online store.[40]
• The SwiftLink-232 is a RS-232 serial port cartridge for the C64/128. It provides up to 38.4 kbit/s transfer rate.[41] Swiftlink was manufactured by CMD, who has stopped producing Commodore gear. There exist several clones such as the Datapump cartridge or the Pitchlink cartridge.[42] The Link-232 is another clone of Swiftlink.
• The Turbo232 cartridge is a high-speed RS-232c modem interface for Commodore 64 or 128 computer. It provides up to 230 kbit/s transfer rate, though limited to 57.8 kbit/s for most software.[43] Turbo232 was manufactured by CMD, who has stopped producing Commodore gear.

Proprietary expansion port adapters

• The 1541Ultimate-II emulates a 1541 disk drive for Commodore computers on a cartridge, using MicroSD or USB disks to store virtual floppy disks. The disk can be downloaded through fast, but not fully compatible proprietary disk emulation. Disk connector for fully compatibility is integrated, but not yet supported in software (as for the 1541U-I). Disk content can be browsed through software on the cartridge and navigated through buttons on the device.[4]
• The Comet64 Internet Modem Serial-to-Ethernet device provides an Ethernet connection. See the Comet64 Internet Modem entry under the User Port RS232 section.

• Data transfer alternatives by Bo Zimmerman (updated around 2005): Data Transfers with Commodore Computers
• Disk and tape transfer at The Starcommander pages (updated around 2010) Useful DOS software, Useful Windows software, Useful Linux software, etc.
• Relevant tools listed by World of Fairlight at The C64 tool list.
• Tape transfer and conversion (updated around 2006) Alternatives to WAV-PRG and Audiotap.
• Internet connection: The Internet For Commodore C64/128 Users - a manual from Commodore Homestead.