Written and Maintained by Gregory Nacu

1541 Ultimate II+

Last modified: Jun 30, 2017,  Page views: 363

Home Page: http://www.1541ultimate.net
Categories: memory, network, storage, audio
Compatible: C64, C64c, SX-64, c128*, c128D*, (* Some features not compatible with c128 and c128D)
Price: € 149.95
How to Order: Follow instructions on the order page
Documentation: http://rr.c64.org/wiki/1541_Ultimate
Three 1541 Ultimate II+

Comes in multiple colors

1541 Ultimate II+ with top case open

Circuit board with top case open

1541 Ultimate II+ without its case

Circuit board without its case

Left profile with case. IEC serial, USB, Audio In/Out

Left profile with case. IEC serial, USB, Audio In/Out

Right profile with case. USB, 100Mbps Ethernet

Right profile with case. USB, 100Mbps Ethernet

Extra Hardware

Black IEC serial cable IEC Serial Cable

Similar Hardware

IDE64 v4.2 uIEC/SD Final Expansion 3

My Take

On Twitter, I referred to this piece of kit as The Jesus Device. And in the feature spot in the Buyer's Guide I say that it's almost uncategorizable in its breadth of usefulness.

Well, those were hardly exaggerations. The 1541 Ultimate II+ has a deceptive name. In fact I'd go so far as to say the name is horrible. It made me think it was just some sort of basic 1541 replacement, perhaps even the ultimate 1541 replacement, but essentially just a floppy disk storage alternative. This is completely wrong. The 1541 Ultimate II+ offers a staggering array of brilliant features and functions all packed into a very small, sexy and professional case.

It is a bit costly. At 149 euros it's ~166 USD and around 225 Canadian dollars. But, when you consider what it contains, and what it costs for those products if you buy them as stand–alone solutions, it's actually a bargain. It's an REU upto 16 megabytes, the 1MB REU clone available from Shareware Plus is 40 euros ($60 CAD) all on its own. It contains an RR-Net compatible ethernet adapter, the 64NIC+ from Retro Innovations is $50 USD (45 Euros, $67 CAD). But it also has USB ports into which you can plug storage devices, such as USB Keys, or even Hard Drives and CD-ROM drives. It's super fast if the load routines are standard because it goes through the Expansion port, and it's got an IEC port for backwards compatibility with serial bus calls. The uIEC/SD (without the daughter card) is another $50 USD (45 euros, $67 CAD), and is slower and limited only to SD Card storage. Add those together 40 + 45 + 45 and you're almost up to the price of the 1541 Ultimate II+, but spread across a bunch of devices, you'd need to add the daughter card and a port expander, and we haven't even touched many of the other features of the 1541 Ultimate II+.

Full disclosure, I haven't actually tried this device yet. But what I hear from people on Twitter is that they love it. It's definitely on my short list of Commodore hardware to sneak past my wife. :) If you've purchased one, let us know what you think in the comments below.

I got two. Greatest retro add-on of all time IMHO. Rob O'Hara — Twitter, 2017


  • Full, cycle accurate emulation of two real Commodore 1541 diskdrives.
    • Uses .D64 and .G64 files stored on USB stick
    • Supports .G64 files as well (Read/Write)
    • Configurable IDs
    • Configurable ROM (1541/1541C/1541II or custom)
    • RAMBoard memory expansion (up to 40K)
  • Built-in Speaker; outputs drive and floppy sounds
  • Support for USB storage devices (stick, card reader, and even HD)
  • 100 Mbps Ethernet port (for use with Telnet or FTP)
  • FAT/FAT32 support, with sub-directories and long filenames
  • ISO9660 support with Joliet, for reading .ISO files and access external CD/DVD drives through USB
  • Battery backed up Real Time Clock
  • Command Interface module with UltimateDOS
    • Accessible module through I/O space that allows direct commands to Ultimate-II
    • Ultimate-DOS, I/O space driven direct file access to SD/USB
  • Dual SID implementation, optionally 8 voices each
  • Ultimate Audio module
    • Up to 7 voices of sampled audio simultaneously
    • Accessible through I/O space
    • 8— or 16—bit samples
    • up to 48 kHz sample rate
  • Built-in SID player; plays SID files on either 'real' SID or emulated SID.
  • C64 cartridge emulation
    • Final Cartridge III
    • Action Replay
    • Retro Replay
    • Super Snapshot
    • Turbo Assembler w/ Codenet
    • Epyx Fastloader
    • Custom 8K/16K carts
    • Custom Ocean / System3 carts (up to 512K)
  • Commodore 1750/1764 REU
    • REU Compatible
    • Size selectable from 128K up to 16 MB
    • Can be combined with Retro Replay and SuperSnapshot compatible roms
  • Flexible freezer menu
    • select, mount, create D64 images, browse disk images
    • create new directories, delete files
    • Ultra fast DMA load of single file programs (.PRG files on USB, inside .D64 or .T64)
  • Configuration screen, with resident settings
  • Tape emulation, through special USB3.0 cable to tape port of C64*
    • Load .TAP files to C64
    • Capture tape data from C64 to .TAP file
    • Capture tape data from a datasette and store it as .TAP file
    • Write .TAP files back to tape, using a Commodore tape deck
    • (* Tape emulator cable is an accessory, which is needed to work with tap files.)
  • Totally rewritten firmware, for easier expansion and maintenance


  • Board size: 62 x  90 mm
  • Sturdy ABS plastic case
  • 1M-gate FPGA
  • Full size 6-pin DIN connector (IEC)
  • 5 MB Flash ROM
  • 64 MB DDR2 SDRAM
  • Three USB host ports
  • One 100 Mbps Ethernet port 
  • Stereo audio output
  • Stereo audio input (currently not yet used)
  • Specialty USB 3.0 port with USB 2.0 signals for storage device OR cable to tape adapter board (for C2N emulation), or other future features.