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The initial model has a 10 MHzMotorola 68000CPU, 1 MB of RAM, and lacks a hard drive. The final model was released in 1993 with a 25 MHz Motorola 68030 CPU, 4 MB of RAM, and optional 80 MB SCSI hard drive. RAM in these systems is expandable to 12 MB, though most games and applications do not require more than 2 MB.
The X68000 has graphics hardware similar to arcade video games of the late-1980s, with custom coprocessors supporting scrolling, tiled backgrounds, and large numbers of sprites. Sound is supplied through multiple sound chips supporting 8 channels of FM synthesis and one channel of adaptive differential pulse-code modulation audio, which are mixed down to 2 analog stereo channels via a DAC chip. As such, video gaming was a major use of the X68000.
Operating system
The X68k runs an operating system called Human68k which was developed for Sharp by Hudson Soft. An MS-DOS-workalike, Human68k features English-based commands very similar to those in MS-DOS; executable files have the extension.X. [2]Versions of the OS prior to 2.0 have command line output only for common utilities like "format" and "switch", while later versions included forms-based versions of these utilities. At least three major versions of the OS were released, with several updates in between.
Early models have a GUI called "VS" or "Visual Shell"; later ones were originally packaged with SX-WINDOW. A third GUI called Ko-Window exists with an interface similar to Motif. These GUI shells can be booted from floppy disk or the system's hard drive. Most games also boot and run from floppy disk; some are hard disk installable and others require hard disk installation.
Since the system's release, software such as Human68k itself, console, SX-Window C compiler suites, and BIOS ROMs have been released as public domain software and are freely available for download.[3] Other operating systems available include OS-9 and NetBSD for X68030.[4][5]
Case design
The X68000 has two soft-eject 5.25-inch floppy drives, or in the compact models, two 3.5-inch floppy drives, and a very distinctive case design of two connected towers, divided by a retractable carrying handle. This system was also one of the first with a software-controlled power switch; pressing it signals the system's software to save and shut down. The screen fades to black and the sound fades to silence before the system turns off.
The system's keyboard has a mouse port built into either side. The front of the computer has a headphone jack, volume control, joystick, keyboard and mouse ports. The top has a retractable carrying handle only on non-Compact models, a reset button, and a non-maskable interrupt (NMI) button. The rear has a variety of ports, including stereoscopic output for 3D goggles, FDD and HDD expansion ports, and I/O board expansion slots.
Display
The monitor supports horizontal scanning rates of 15, 24, and 31 kHz and functions as a cable-ready television (NTSC-J standard) with composite video input. It was a high quality monitor for playing JAMMA-compatible arcade boards due to its analog RGB input and support for all three horizontal scanning rates used with arcade games.
Disk I/O
Early machines use the rare Shugart Associates System Interface (SASI) for the hard disk interface; later versions adopted the industry-standard Small Computer System Interface (SCSI). Per the hardware's capability, formatted SASI drives can be 10, 20 or 40 MB in size and can be logically partitioned as well.
Human68K does not support the VFAT long filenames standard of modern Windows systems, but it supports 18.3 character filenames instead of the 8.3 character filenames allowed in the FAT filesystem. By default, Human68K will not consider any additional characters beyond the first 8 without the use of a special driver, therefore files and folders that are named the same when viewed through a 8.3 filename but different when viewed through a 18.3 filename will be considered the same. Human68K is case sensitive and allows lower case and Shift JIS encoded Kanji characters in filenames, both of which cause serious problems when a DOS system tries to read such a directory. If a X68000 user restricts themselves to use only filenames according to the 8.3 characters scheme of DOS, using only Latin upper case characters, then a disk written on the X68000 is fully compatible with other Japanese standard platforms like e.g. the NEC PC-9800, the Fujitsu FMR and FM Towns computers. The Japanese standard disk format used by the X68000 is: 77 tracks, 2 heads, 8 sectors, 1024 bytes per sector, 360 rpm (1232 KiB).
Expansion
Many add-on cards were released for the system, including networking (Neptune-X), SCSI, memory upgrades, CPU enhancements (JUPITER-X 68040/060 accelerator), and MIDI I/O boards. The system has two joystick ports, both 9-pin male and supporting Atari standard joysticks and MSX controllers. Capcom produced a converter that was originally sold packaged with the X68000 version of Street Fighter II that allowed users to plug in a Super Famicom or Mega Drive controller into the system. The adapter was made specifically so that users could plug in the Capcom Power Stick Fighter controller into the system.
Sprite count: 128 sprites on screen, 32 sprites per scanline, 256 sprite patterns in VRAM (can be multiplied up to 512 sprites on screen with scanline raster interrupt method[12])
Sprite size: 16×16
Colors per sprite: 16 colors per palette, selectable from 16 palettes (out of 65,536 color palette)
Sprite colors on screen: 256 (out of 65,536 color palette)
Sprite tile size: 8×8 or 16×16
Sprite tile count: 128 (16×16) to 512 (8×8) on screen, 256 (16×16) to 1024 (8×8) in VRAM
Other specifications
Expansion: 2 card slots (4 on Pro models)
I/O Ports:
2 MSX compatible joystick ports
Audio IN / OUT
Stereo scope/3D goggles port
TV/monitor Control
RGB/NTSC Video Image I/O
Expansion (2 slots)
External FDD (up to 2)
SASI/SCSI (depending on model)
RS232 serial port
Parallel port
Headphone and microphone ports
Floppy Drives:
Two soft-eject 5.25″ floppy drives, 1.2 MB each
Two 3.5″ floppy drives, 1.44 MB each (compact models)
Hard Disk: 20-80 MB SASI/SCSI (depending on model)
Operating Systems: Human68k (MS DOS-alike developed by Hudson), SX-Windows GUI
^ abcdJapan, Information Processing Society of. "X68000-Computer Museum". museum.ipsj.or.jp. Archived from the original on 2014-10-02. Retrieved 2014-09-07.
^Yoshida, Koichi (12 September 2001). "超連射68K 開発後記". Yosshin's web page (in Japanese). Archived from the original on 12 May 2019. Retrieved 2020-03-06. (Translation by Shmuplations. Archived 2019-07-02 at the Wayback Machine).
