Classic computing fanatic Travis Smith has designed a brand new accent for the traditional Commodore 64 microcomputer, and its follow-up the Commodore 128, providing a spread of options in a single Teensy 4.1-powered cartridge: the TeensyROM.
“TeensyROM is a ROM [Read-Only Memory] emulator, tremendous quick loader, MIDI Host [and] System, and Web interface cartridge for the Commodore 64 & 128, based mostly on the Teensy 4.1,” Smith explains of his creation. “Compatable with C64 and C128 machines/variants, NTSC and PAL supported.”
At its easiest, the TeensyROM can work as a strategy to load cartridge ROM photographs into an actual Commodore 64 or suitable, loaded from the Teensy’s personal flash storage or from a microSD Card or USB storage system. It might probably additionally load program information straight, and at a significantly quicker pace than official Commodore storage gadgets just like the 1541 floppy drive or Datasette cassette tape deck.
That is solely a part of the TeensyROM’s feature-set, although. The system may also function a MIDI enter or output, permitting you to utilize the Commodore 64’s well-known MOS Expertise 6581 Sound Interface System (SID) chip from a USB MIDI keyboard — or to drive an exterior MIDI system from the Commodore 64 itself. It is also doable to stream MIDI- or SID-format information from a contemporary PC and listen to them performed on the unique {hardware}. Lastly, the gadget additionally gives web connectivity over an Ethernet port — emulating a Swiftlink cartridge with 38.4kbps modem hooked up.
“I selected the Teensy 4.1 for this mission to reap the benefits of all its exterior interface capabilities (USB Host & System, SD Card, Ethernet),” Smith explains. “I additionally wished to make use of its many IO [Input/Output] pins to do ‘direct’ interfacing so it may be largely software program outlined.”
The TeensyROM has been revealed to GitHub beneath the permissive MIT license with full supply code, {hardware} design information, and a 3D-printable case, with Smith saying it was designed for these “medium expert” at soldering; he’s additionally promoting fully-assembled models on his Tindie retailer for $59.
