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The TeensyROM Multifunction Cartridge for the C64 & C128, designed by Travis Smith. This plug and play cartridge is designed for use with the Commodore 64 and 128, and offers a multitude of functions in one sleek device. Whether you're looking to load multiple programs or games with ease, the TeensyROM cartridge has got you covered. Say goodbye to the hassle of swapping cartridges - this multipurpose cart is the perfect solution for any C64 enthusiast. Upgrade your computing experience with the TeensyROM Cart and unlock the full potential of your Commodore 64 system.
 
 - Superfast Loader
 - MIDI Connectivity
 - Connect to the Internet
 - Use MicroSD or USB
 
TeensyROM is a ROM emulator, super fast loader, MIDI Host+Device and Internet interface cartridge for the Commodore 64 & 128, based on the Teensy 4.1
 
This is a fully assembled and tested TeensyROM+ board, including a pre-loaded Teensy 4.1.   It has a selection of built-in utilities and games, ready to plug and play! 
 
TeensyROM is an open source project, and offered here with the kind permission of the developer.
 
- PCB has ENIG (Electroless Nickel Immersion Gold) finish
- USB flashdrive included. 
- 8GB MicroSD included (Supports up to 32GB)
 
TeensyROM Main Features:
Compatable with C64 and C128 machines, NTSC and PAL supported
TeensyROM compatability has been fully validated on many different NTSC and PAL machines: C64, C64C, SX-64, and C128
 
Super Fast Loading of .CRT .PRG & .P00 Files directly from:
  • USB Thumb Drive
  • Micro SD card
  • Teensy Internal Flash Memory
  • Transfer directly from PC (Windows app included)
  • NFC Loading system available to quickly select/load with NFC tags (Tapto)
 
MIDI in/out via USB Host Connection:
  • Play your SID with a USB MIDI keyboard!
  • Use with popular software such as Cynthcart, Station64 etc
  • Supports all regular MIDI messages in and out
    • Can use your C64 to play a MIDI sound capable device.
  • Sequential, Datel/Siel, Passport/Sentech, and Namesoft MIDI cartridges emulated
  • Use a USB Hub for multiple instruments+thumb drive access
 
MIDI in via USB Device Connection:
  • Stream .SID or .MIDI files/data from a modern computer directly to your Commodore's SID chip!
  • Play MIDI files out of your PC into C64 apps such as Cynthcart or the MIDI2SID app
  • Play .SID files out of your PC using the ASID MIDI protocol to hear any SID file on original hardware.
 
Internet Communication via Ethernet Connection
  • Surf the web with built-in web browser, including URL bookmarks and high speed file downloads
  • Connect to your favourite C64/128 Telnet BBS
  • Use with released software such as CCGMS, StrikeTerm2014, DesTerm128, etc
  • Swiftlink cartridge + 38.4k modem emulation
  • Send AT commands from terminal software to configure the Ethernet connection
  • Sets C64 system time from internet
 
Firmware Updates Directly from SD card or USB Thumb-drive
  • Just drop the .hex file on an SD card or USB drive, no need for extra software to update.
Key parameters stored in internal EEPROM
  • Startup, Ethernet, timezone, etc retained after power down.
 
These units are kindly made and supplied to us by Travis Smith, the designer & developer of TeensyROM.
 
Also Available:
-  TeensyROM 3D Printed Case
-  NFC Reader/Writer

TeensyROM+ (Plus) Multipurpose Cart for C64 & C128

From £89.00Sale Price

5% OFF TWO OR MORE C64 CARTS

Quantity

  • PRODUCTION NOTES

    TeensyROM designed by Travis S/Sensorium is a ROM emulator, super fast loader, MIDI Host/Device, Internet interface cartridge and more for the Commodore 64 & 128, based on the Teensy 4.1

     

    More Info at: github.com/SensoriumEmbedded/TeensyROM

  • PCB DESIGN

    Component selection was done using parts large enough (SOIC and 0805s at the smallest) that any soldering enthusiast should be able to assemble themselves. Since high volume production isn't necessarily the vision for this device, 2 sided SMT was used to reduce the PCB size while still accommodating larger IC packages.

    A note about overclocking The Teensy 4.1 is slightly "overclocked" to 816MHz from FW in this design. Per the app, external cooling is not required for this speed. However, in abundance of caution, a heatsink is specified in the BOM for this project. In addition, the temperature can be read on the setup screen of the main TeensyROM app. The max spec is 95C, and there is a panic shutdown at 90C. In my experience, even on a warm day running for hours with no heatsink, the temp doesn't excede 75C.

  • YOUTUBE VIDEOS

    This YouTube Playlist contains all the latest TeensyROM demo videos, such as:
    Real-time video/audio capture of menu navigation and loading/running/emulating various programs/cartridges
    Demo using Cynthcart and Datel MIDI emulation to play with a USB keyboard
    MIDI ASID Demo: Stream .SID & .MIDI files directly to your C64/SID
    Web Browser and internet file download demo

  • GITHUB

    Full details along with TeensyROM docs, information, firmware updates and accompanying Windows app are available at github.com/SensoriumEmbedded/TeensyROM

  • CUSTOMER COMMENTS

    "I bought the teensyrom the device is pure genius. I can now play all my old favorites in 0.5 a second" TBJ

  • TR+ FEATURES OVERVIEW

    TeensyROM+ (TR+) New Features Overview

    The TeensyROM+ (PCB v0.4) represents the next generation of TeensyROM hardware, retaining 100% of the standard feature set and codebase while introducing an entirely new tier of advanced capabilities.

     

    The Foundation: Real Bus-Mastering DMA

    While the original TeensyROM could assert the DMA line to pause the C64 CPU (enabling features like CRT bank-swapping), it never took actual control of the address and data buses.

     

    TR+ introduces dedicated bus-buffering hardware for full bi-directional control of the address bus, data bus, and $R/\overline{W}$ line, operating as a genuine second bus master. This hardware foundation enables live KERNAL replacement, a full 512KB RAM Expansion Unit (REU), and remote memory access.

     

    TR+ Specific Additions

    • Kernal Replacement: Load custom KERNAL ROM images directly from the SD or USB file browser using Shift-K. Preferences are saved in EEPROM and applied via the standard "Exit to BASIC" (F2) path or when launching a .prg file.

    • 512KB REU (RAM Expansion Unit): Emulates a hardware-compatible REU detectable by C64 software. Pre-load binary images via Shift-R or by selecting .reu files directly, and save active REU contents to auto-numbered files on the fly. Fully validated against the REU-Checker and CMD 1750/1750XL REU Test suites.

    • Freezer Cartridge Support: Natively emulates Action Replay and Super Snapshot V5 (both PAL and NTSC), accessible on demand via the new physical Alt button.

    • Remote DMA Memory Access: Exposes WriteC64Mem and ReadC64Mem functions, granting external applications real-time read and write access to C64 memory over Serial or Ethernet (powering utilities like c64cast).

    • Battery-Backed Real-Time Clock: Features an onboard CR1225 coin-cell holder to maintain accurate time across power cycles without requiring manual Ethernet synchronization or hardware soldering, keeping BASIC's TI/TI$ variables accurate immediately upon boot.

    • External Reset Detect: Responds to external reset signals (from the C64U button, User port, or custom wiring) identically to pressing the onboard TR menu button.

    • Programmable Alternate Button: Assign the physical Alt button to multiple functions when not engaged in freezer or REU duties:

       

      • AutoLaunch (Default): Launch a designated game or utility instantly.

      • Pause/Unpause: Halt and resume the C64/128 mid-session, indicated by a flashing button LED.

      • System Actions: Jump to the TR menu, reboot TR, or disable the cartridge entirely.

    • TR+ Expansion Port Test: A complete hardware diagnostic suite for the C64 cartridge port that exercises individual signals ($(\text{address/data}, \text{DMA}, \text{BA}, R/\overline{W}, \text{IO1}/\text{IO2}, \text{IRQ}, \text{NMI}, \text{ROMH}/\text{ROML}/\text{GAME}/\text{EXROM})$ via Walking Ones, Cascading Ones, and extended burn-in looping modes.

  • C64 ULTIMATE / ULTIMATE 64

    Using TR+ with a Commodore 64 Ultimate / Ultimate64

    When operating TR+ on a C64 Ultimate or Ultimate64 motherboard, configure the system settings as follows for optimal compatibility with DMA-driven features:

    Setting Recommended Value
    Cartridge Preference External
    Bus Operation Mode Writes

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