Dragon 32/64

src: upload.wikimedia.org

The Dragon 32 and Dragon 64 are home computers built in the 1980s. The Dragons are very similar to the TRS-80 Color Computer, and are produced for the European market by Dragon Data, Ltd., in Port Talbot, Wales, and for the US market by Tano from New Orleans, Louisiana. The model numbers reflect the main differences between the two machines, which have 32 and 64 kilobytes (32,768 and 65,536 bytes) of RAM, respectively.

Video Dragon 32/64

Riwayat produk

In the early 1980s, the UK home computer market was booming. New machines are released almost every month. In August 1982, Dragon Data joined in a battle with Dragon 32; Dragon 64 followed a year later. Computers sold well enough at first and attracted the interest of some independent software developers, especially Microdeal. A magazine, Dragon User , also began publishing shortly after the launch of the machine.

In the personal home computer market, where the game is a significant driver, the Dragon suffers from its lower graphics capabilities than contemporary machines like Sinclair ZX Spectrum and BBC Micro.

The dragon also can not easily display lowercase letters. Some of the more sophisticated applications will synthesize them using high-resolution graphics mode (in the same way that user-defined characters will be designed for pure graphics applications like games). The simpler programs are only managed without lowercase. This effectively locks it away from the blooming education market.

As a result of this limitation, Dragon was not commercially successful, and Dragon Data collapsed in June 1984. It was acquired by Spanish company Eurohard S.A., filing for bankruptcy in 1987.

In the United States it is possible to purchase a new Tano Dragon in the box until early-2017 from California Digital, a company that buys stock leftovers.

Maps Dragon 32/64

Technical notes

Hardware and peripherals

The Dragon is built around the Motorola MC6809E processor running at 0.89 MHz. It is an advanced 8-bit CPU design, having, among other things, limited 16-bit capabilities. In terms of raw computing power, Dragon defeats most of its contemporary rivals based on the older MOS 6502 Technology, but this makes little difference in the market where graphics and game capabilities are much more important to consumers.

It's possible to increase computer speed by using POKE 65495.0 which speeds up the resident BASIC ROM interpreter, but temporarily disables the correct functionality of the tape/printer port. Manufacturing variance means that not all Dragons can function at this higher speed, and the use of this POKE may cause some units to crash or unstable, albeit without permanent damage. POKE 65494,0 returns speed to normal. POKE 65497.0 pushes speed but higher but the view disappears until a slower speed is restored.

The Dragon also uses SN74LS783/MC6883 Synchronous Address Multiplexer (SAM) and MC6847 Video Display Generator (VDG). I/O is provided by two MC6821 Peripheral Interface Adapters (PIAs). Many Dragon 32s are upgraded by their owners to 64 kB of memory. Some more extended to 128 kB, 256 kB, or 512 kB, with a memory control unit/built-in memory management unit (MMU).

Various devices are available for Dragon 32/64, and on top of these there are add-ons like Dragon's Claw that give Dragons access to various BBC Micro accessories (a very important factor in the UK) market). Although no machine has a built-in disk operating system (the tape that became the default data storage mechanism on the home computer market at the time), DragonDOS is provided as part of the disk data control interface of Dragon Data Ltd. Various external ports (based on time standards), including the RS-232 standard on 64, also allow hobbyists to install a variety of equipment.

Unusual feature is the monitor port for computer monitor connection, as an alternative TV output. It's rarely used because of the cost of a dedicated monitor at that time. The actual port is a Composite Video port and can be used to connect the Dragon 32 to the most modern TV to provide a much better picture.

The Dragon uses an analog joystick, unlike most time systems that use cheaper but more flexible digital systems. Other uses for joystick ports include light pens.

Tony Clarke and Richard Wadman explain the specifications for the Dragon.

The units have powerful motherboards in large cases, reminiscent of BBC Micro, and are more tolerant of home modifications than some of their contemporaries, who often have their components crammed into the smallest space possible.

Video mode

Dragon's main display mode is the text 'black on green' (actually black is deeper green and greener). The only possible chart in this mode is the base of the quarterly block.

It also has a choice of five high-resolution modes, named PMODE 0-4, which alternates monochrome and four colors in higher resolution in a row, culminating in black and white 256ÃƒÆ'Ã¢ â‚¬ "192 PMODE 4. Each mode has two color palettes which allow. Unfortunately, this was rather tacky and caused the system to fare poorly in visual comparison with other home computers at the time. It is also not possible to use standard printing commands to print text in graphical mode, causing software development difficulties.

Full scanline based on 64- 192 "semi-graphic" modes is also possible, although the imbalance of resolution and their programming difficulties (they are inaccessible via BASIC) means they are not often used.

System disk

A complete Operating System Disk is manufactured for Dragon by third-party suppliers, Premier Microsystems located near Croydon. The system is sold as a "Delta" disk operating system. Although Premier offers Delta systems to be marketed by Dragon himself, Dragon is unhappy that third parties hijack the standards for their computers, and produce their own rival DragonDOS system by making it clear that third-party delivers are not compatible with standard Dragon Disk systems.

Inevitably, with Delta head start, the software is marketed in both systems, but rarely both. The result is an inevitable confusion with an annoyed customer because certain software is not available for their Disk system.

System software

Dragon comes with a Microsoft BASIC translator in 16 KB ROM. The BASIC seems to be synonymous with Extended Basic Computer Tandy Color.

Unlike modern PCs with operating systems on disk, Dragon starts right from the start. Some software providers also produce compilers for BASIC, and other languages, to generate binary code (or "machines") that will run many times faster and make better use of small system RAMs. Toward the end of his life, Dragon Data generates an assembler/disassembler/editor suite called Dream .

In addition to the DragonDOS disk operating system, Dragon 32/64 is capable of running several others, including FLEX, and even OS-9 that brings UNIX-like multitasking to the platform. Dragon equipped with memory and equipped with MMU can run OS-9 Level 2.

Games

Originally, Dragon was supported by a large British software company with a popular game version of another system ported to Dragon. Examples of the best-selling games available for Dragon include Arcadia (Imagine), Chuckie Egg (A & amp; F), Manic Miner and the sequel < i> Jet Set Willy (Software Project), Hunchback (Ocean) and Football Manager (Addictions). There are also companies that concentrate on Dragon like Microdeal. Their characters Cuthbert appear in some games in Dragon with Cuthbert Goes Walkabout also being converted to Atari 8-bit and Commodore 64 systems.

Due to the limited graphics mode of the Dragon, the converted game has a distinctive appearance with a color game normally played on a green or white background (not the more common black on other systems) or games with high definition graphics must run in black and white.

When the system is stopped, support from software companies also effectively ends. However, Microdeal continued to support Dragon until January 1988. Some of the last games they developed for Dragon in 1987 such as Tanglewood and Airball were also converted to 16-bit machines such as Atari ST and Amiga.

Differences from TRS-80

Both Dragon and TRS-80 Color Computer are based on the design of the Motorola datasheets for the MC6883 SAM (MMU) chip for memory management and peripheral control.

The system is similar enough so that significant fractions of the compiled software generated for one machine will run on the other. Software that runs through the Basic default interpreter also has a high degree of compatibility, but only after they are re-tokenised, which can be achieved easily by transferring via cassette with the appropriate option.

It is possible to permanently convert the Color Computer into a Dragon by swapping the original Color Computer ROM and reassembling the keyboard cable.

The Dragon has an additional circuitry to make the VDG MC6847 compatible with European 625-line European standards, rather than the US NTSC 525-line standard, and Centronics parallel printer ports are not present on the TRS-80. Some models are produced with NTSC video for the US market.

Dragon 32 vs. Dragon 64

Apart from the amount of RAM, 64 also has a functional RS-232 serial port that is not included on the 32. The small difference between the two Dragon models is the outer color of the case; Dragon 32 is creamy and 64 is light gray. In addition to the case, branding and serial port Dragon 64, these two machines look the same. The Dragon 32 can be upgraded to Dragon 64.

DRAGON 32/64 - DONKEY KING - MICRODEAL - 1984 - YouTube

src: i.ytimg.com

Reception

BYTE wrote in January 1983 that Dragon 32 "offers more features for money than most of its [British] rivals", but "nothing special about it". The review describes it as a redesigned and inexpensive Color Computer with 32K RAM and a better keyboard.