1541 Ultimate
1541 Ultimate (often abbreviated 1541U) is a peripheral,[1] primarily an emulated floppy disk and cartridge emulator based on the FPGA Xilinx XC3S250E, for the Commodore 64 home computer. It became available in 2008.
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The unit is developed by Gideon Zweijtzer and is a cartridge that can emulate other cartridges such as the Commodore REU, Action Replay, The Final Cartridge III, Super Snapshot V5, Retro Replay or TurboAss with Codenet-support, and an almost fully compatible[2] (including JiffyDOS support[3] FPGA-cloned Commodore 1541 (including 1541, 1541C, and 1541 II models[4]) floppy disk unit that can use Commodore 64-compatible files like .D64/.G64 disc images or .PRG files via a SD card reader.[5] Additionally, the 1541 Ultimate is suitable for making archives of floppy disks.[6] All units after the initial production have 32 megabytes of RAM, while the original production run only had 16 megabytes.
The 1541 Ultimate is capable of running both CP/M and GEOS.[7]
In 2010, the 1541 Ultimate II was developed. The Ultimate II is about 30% smaller than the 1541 Ultimate, comes in a plastic case,[8] and adds support for dual SIDs (plus a SID/MOD player),[9] a USB host controller, tape emulation via a tape adapter[10] (though use with a Commodore 128D requires modification[11]), a real-time clock (for accurate file date and time), and the SD card slot is replaced by a microSD card slot.[2] In addition, all firmware and VHDL code for the Ultimate II is available under an open source GPLv3 license,[12] allowing hobbyists and others to freely modify all aspects of its functionality, including the FPGA-emulated hardware.
The 1541 Ultimate has an option for on-board Ethernet, while the 1541 Ultimate II supports Ethernet via a compatible USB to Ethernet adapter.[2]
Besides being useful to retrocomputing hobbyists,[4] it has also found use in educational laboratory settings.[13]
In 2017 the Ultimate II+ was released with the following feature differentiation from the II:
Removal of the MicroSD slot, More USB ports, Integrated Ethernet, Dual Flash, Integrated Speaker, External power supply connector with auto-switch over circuit, Improved power supply circuits, and a slightly bigger and faster FPGA, as to control the new features. [14]
The II and II+ share a firmware image and the software features are substantially similar.
See also
References
- Loguidice, Bill; Barton, Matt (2014). Vintage game consoles : an inside look at Apple, Atari, Commodore, Nintendo, and the greatest gaming platforms of all time. Focal Press. p. 117. ISBN 978-0-415-85600-3.
- Parker, Nigel, ed. (Dec 2009). "Commodore Free talk to Gideon Zweijtzer". Commodore Free Magazine. Vol. 3, no. 35. pp. 15–16. Archived from the original on 2015-03-11. Retrieved 2016-01-30.
- "1541 Ultimate II". breadbox64. Archived from the original on 2016-01-30.
- James Grahame (2010-03-25). "Replace Your Commodore 64 Disk Drive With Flash Memory". Retro Thing. Archived from the original on 2015-10-17. Retrieved 2016-01-30.
- Dillon, Roberto (2015). Ready: A Commodore 64 Retrospective. Springer. p. 125. ISBN 978-981-287-340-8.
- Wiebo de Wit (2014-11-04). "1541 Ultimate II Guide 4 : Floppy Copy". DevDef. Archived from the original on 2015-01-22. Retrieved 2016-01-30.
- James Monkman (2011-05-30). "Running GEOS on the Ultimate 1541-II (C64)". RGCD. Archived from the original on 2015-06-30. Retrieved 2016-01-30.
- Ilkka Sjöstedt (2013-04-13). "1541 Ultimate, original vs Ultimate-II". Archived from the original on 2015-01-01. Retrieved 2016-02-08.
- "1541 Ultimate-II - Is this the ultimate device for a C64/128? [ Hardware Review ]". Indie Retro News. 2015-01-09. Archived from the original on 2015-01-09. Retrieved 2016-01-30.
- "1541 Ultimate II technical documentation" (PDF).
- Carsten Jensen (2014-12-25). "Extending the 1541Ultimate 2 tape extender". Retro Commodore. Archived from the original on 2016-01-08. Retrieved 2016-01-30.
- "1541 Ultimate Open Source announcement and build requirements".
- Montfort, Nick; Federova, Natalia (2012-04-25). Creative Material Computing in a Laboratory Context (PDF) (Technical report). TROPE. Cambridge, Massachusetts: The Trope Tank, Massachusetts Institute of Technology. p. 7. hdl:1721.1/78888. 12-03. Retrieved 2015-02-08.
- "Home". Archived from the original on 2017-04-08.