1541 Ultimate

Technical Info
ROM	2 MB flash
RAM	32.5 MB
Hardware features	3 Buttons - Freeze, Reset and 1541U Freeze
Manual	PDF: 28 pages from 1541ultimate.net PDF: 2 pages scan of suplied documentation sheet
CRT ID	None
Programming	See 1541ultimate.net

This article as well as WiPeD 1541 Ultimate are describing the v1 version of this nice hardware - v2 is already due and 1541 Ultimate-II is the current revision. This article needs an update badly - for recent news and data please check: 1541ultimate.net

1541U is one of the ultimate cartridges for the C64 and regular checks at

1541ultimate.net

are a strict requirement for any C64 cartridge lover. Since the 1541U emulates a range of freezer cartridges and allows re-flashing them it is a perfect platform for testing ROMs on the real machine. Cartridge emulation is pretty good and should suit most requirements. This emulation also made the 1541u enter the charts here. There are some problems left as with any other hardware but since this baby can be updated and firmware is publicly available we see a bright future for it.

The awesome list of features below speaks for this fine C64 hardware extension by itself just one important info appears to be missing: the stereo audio output mentioned towards the end of the hardware specs allows to connect speakers to the 1541U. The speakers will then produce original 1541 sound including compositions like 1541-Music or own tracks done with e.g. Drive Composer.

Mostly from the 1541Ultimate Website:

Features

• Full emulation of a real Commodore 1541 diskdrive.
  • Uses .D64 files stored on SD card
  • Supports .G64 files as well (Read only)
  • Configurable ID
  • Configurable ROM (1541/1541C/1541II or custom)
  • RAMBOard memory expansion (16K)
• Secondary 'IEC-drive' for direct access to FAT filesystem
  • Can be used in stand alone mode to mount disks into the emulated 1541.
• FAT/FAT32 support, with sub-directories and long filenames
• Supports SD V1.1 cards as well as SD V2.0 in High Capacity mode (SDHC)

1541Ultimate-II Board

The new 1541U-II will be around soon (including a case).

• C64 cartridge emulation:
  • Final Cartridge III
  • Action Replay
  • Retro Replay
  • Super Snapshot
  • Turbo Assembler w/ Codenet
  • Ocean
  • 8k/16k game

for details see [CRT_ID]

This 1541Ultimate-I with ethernet found an awesome home. (Click image for more info.)

• Commodore 1750/1764 REU
  • REU Compatible
  • Size selectable from 128K up to 16 MB
  • Can be combined with Retro Replay and SuperSnapshot compatible roms
• Integrated RR-net compatible Ethernet port
  • Available as an option on a new order only!
  • No flimsy stackup board, but fully integrated.
• Flexible freezer menu
  • select, mount, create D64 images, browse disk images
  • create new directories, delete files
  • Ultra fast DMA load of single file programs (directly from SD / from a .D64 with automount and from a .T64 file)
• Configuration screen, with resident settings
• Load of last disk on power up
• 'Stand-alone mode'
  • keeps the cartridge port free
  • powered through Mini-USB connector
  • controlled through buttons and IEC.
  • *NO* Ethernet support yet in stand alone mode!

Planned features

• Built-in copier
• ...

Hardware Specifications

• Board size: 68 x 100 mm
• 250k-gate FPGA
• Full size 6-pin DIN connector (IEC)
• 512 kB SRAM
• 2 MB Flash ROM
• 32 MB SDRAM
• Full size MMC / SD card compatible (Mini/Micro SD possible with adapter)
• Stereo audio output
• 6-pin expansion pin-header for connection to tape port (for C2N emulation), or other future features.

Last Updated ( Tuesday, 13 January 2009 09:03 )

Future

As of this writing the 1541U-II is under development. It will feature

• the board itself is about 30% smaller than the 1541U;
• it has a MicroSD connector, instead of a full-size SD;
• it has a real-time-clock function, for correct file time and date;
• it has a larger FPGA, which enables the implementation of more features;
• it has a USB Host port, which can be used to connect USB-sticks;
• it is targeted to have a suitable case for the device.

Known Problems

Needs detailed explanation.

• Freezer bug
• Ethernet bug

Notes

• codebase64.org has "How the 1541U freezer works" or "Safely freezing the c64" by Gideon Zweijtzer
• Commodore Free Issue 35 has an interview with Gideon Zweijtzer
• Lotek64 Issue 26 has a german review on the 1541 Ultimate

• Wikipedia deleted the page on the 1541 Ultimate (twice actually). Due to "Unambiguous advertising or promotion" the last time. Well - WiPeD 1541 Ultimate tries to recover it.

Software

Just three basic categories as of yet.

Firmware

Please note that all these archive contents are available from 1541ultimate.net and newer versions may be available there!

• 1541u_Firmware_v17beta.rar - includes 1541u-firmware-v17b.pdf and 1541u_v1.7beta.zip
• 1541u_Firmware_v16.rar - includes 1541u-firmware-v16.pdf and 1541u_v1.6.zip
• 1541u_Firmware_v15.rar - includes 1541u-firmware-v15.pdf and 1541u_v1.5.zip

inofficial

• 1541-Ultimate-MK1-2.6d.o918r4.zip - Obliterator918′s custom 1541 Ultimate Firmware for “mark 1″ units, Version 2.6d.O918.4 Based on Gideon’s SVN revision 131.

Software requiring special features

Listing software that requires one or another special feature only available on "modern" hardware and/or emulators, such as the 1541U, [Chameleon] or VICE.

16MB REU

• bluREU by Crest

Note: 16MB REU is also implemented by the [Chameleon] and can also be emulated by VICE.

Ultimate Audio

"Ultimate Audio" is a custom 7(?) channel PCM output, which is available in 1541U-II Firmwares 2.5+

• UltimateAudio simple synth by Freshness
• Ultimate Audio MOD Player by Freshness

Incompatible software

Things that should work but do not.

Weblinks

• 1541ultimate.net
• Quick Guide to the 1541 Ultimate.zip at Goin' for Gold and mags.c64.org
• 1541U source code repository - svn co https://xp-dev.com/svn/gideonz_1541Ultimate/ gideonz_1541Ultimate
• 1541U-II source code repository - svn co https://xp-dev.com/svn/1541UltimateII/ 1541UltimateII