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Info for coco


====== Tandy TRS-80 Color Computer (1980) and Color Computer 2 (1983), Dragon Data Ltd. Dragon 32 (1982) and Dragon 64 (1983), Tano Dragon 64 (1983), Prologica CP-400 (1984) ======




===== Features =====

* CPU: Motorola 6809 E 0.895 MHz (or 1.79 MHz) [CoCo, CoCo2], Motorola MC6809EP 0,9 MHz + Motorola MC-6847 Video Display Generator [Dragon 32, Dragon 64, CP-400]
* RAM: 4 KB up to 64 KB [CoCo], 16k, 32k and 64k, depending on models [CoCo2], 32k [Dragon32], 64k [Dragon 64], 16k and 64k, depending on models [CP-400]
* ROM: 8 KB [CoCo], 8k (Color Basic) but later models had 16k (Extended Color Basic) [CoCo2], 2 x 8K or 16K EPROM comprising Microsoft Extended BASIC [Dragon32], 32 kb [Dragon 64], 16k [CP-400]
* Text Modes: max : 16 x 32, min : 16 x 8
* Graphic Modes: Several graphic modes, max : 256 x 192 (with 2 colors)
* Colors: 9 [CoCo, CoCo2, CP-400], 8 [Dragon32, Dragon 64]
* Sound: 1 voice (6-bit DAC) [CoCo, CoCo2], 1 voice, 5 octaves with the Basic, 4 voices, 7 octaves with machine code [Dragon 32, Dragon 64], 4 virtual channels [CP-400]
* I/O Ports: Tape, RGB, Joystick (2), Monitor, Cartridge, Serial RS232
* Keyboard: QWERTY calculator type keyboard [CoCo], QWERTY Mechanical keyboard [Dragon 32, Dragon 64], Full-stroke 53-keys keyboard + Arrow keys, BREAK, CLEAR, SHIFT (x2) [CoCo2]
* OS: OS-9 Level 1
* Built In Language: Tandy (Microsoft) BASIC interpreter [CoCo, CoCo2], Microsoft Extended Basic & Basic Interpreter 1.0 [Dragon 32, Dragon 64], Color Basic v1.0 [CP-400]



===== Usage =====

== Cassettes ==

MESS supports .cas files. Not all of these work; don't panic.

You can pick the cassette image you wish to run from the FILE MANAGER in the Tab/Options menu. Once you've selected the image, go back into the CoCo emulation, and use "scroll lock" to set it back in keyboard emulation mode.

If it's a BASIC program, type
CLOAD
RUN

If it's an assembler programs, type
CLOADM
EXEC

If you include the name of the file (eg. CLOAD "PROG") it will skip any files preceding the one you specified.

== Snapshots ==

MESS supports .pak files. Go to file menu pick the .pak. It should automatically start running the game. If it does not run, it isn't supported yet.

== Cartridges ==

MESS supports .rom files. Go to file menu and pick the .rom. Reset to CoCo and it will start running the game. If it does not run it isn't supported yet.

== Floppies ==

MESS supports .dsk files. Basically the same as cassette images, except you insert the image in Floppy Disk#1 from the file manager. Once you return to the coco emulation, switch back to keyboard emulation mode by pressing SCROLL LOCK and type
DIR

To load a binary file (/BIN), type
LOADM "GAME/BIN:1"
EXEC
(replacing the ":1" in LOADM with the appropriate drive designation ":0" through ":3" )

To load a basic file (/BAS), type
LOAD "GAME/BAS:0"
RUN

//Thanks to "Axe" for the command summary.//



===== Known Issues =====

Requires full keyboard emulation. At startup, full keyboard emulation mode is enabled by default. Whilst in full keyboard emulation mode, some key associated functionality may be disabled (like the ESC key for EXIT). The keyboard emulation mode is toggled using the
scroll_lock key.



===== History and Trivia =====

The Tandy TRS-80 Color Computer was known to be called "CoCo" (Color Computer) by its users. It uses its own version of BASIC, "Tandy Color BASIC", instead of the Microsoft BASIC (this was the main difference with Dragon 32, and the main reason for the partial compatibility between the two machines: the two BASICs use different tokens so they are not binary compatible).
It was followed by the TRS-80 Color Computer II in 1982.

The TRS 80 Color Computer 2 (coco2) replaced the Color Computer "Model 1" in 1983. It has the same characteristics than the Model 1 but has a better keyboard and a more integrated circuitry.

There were several models of the Coco2, some with only 8k ROM (Color Basic) called Standard Color Computer 2, and others with 16k ROM (Extended Color Basic) called the Extended Color Computer 2. Some later models differ also in RAM capacity (16k, 32k or 64k).
It was replaced with the TRS-80 Color Computer 3 in 1986.

The Welsh Dragon 32 was one of the CoCo many clones and it enjoyed a pretty good success in Europe. Its ROM holds the Operating System and a version of the Microsoft Extended BASIC.

One of its characteristics is partial compatibility with the Tandy TRS 80 Color Series. They can use same peripherals and some cartridges, but most ROM calls will fail on the other computer. However, the Dragon did have at least two advantages over the first TRS-80 Color computer:
* a typewriter-style keyboard that was somewhat better than the Tandy's calculator-like keys
* a Centronics parallel-printer port.

Two years later, Welsh launched the DRAGON 64 which has the same characteristics except the added memory (64k RAM instead of 32k), a RS232c port and minor ROM changes.

The Dragon 64, launched in 1983, was exactly the same computer as the Dragon 32, except that it had 64k RAM instead of 32k, an OS9 operating system and a RS232C connector.

The Extended Basic has been modified to provide RS232 I/O calls, to remove the USR bug present in the Dragon 32 ROM and to add calls allowing the additional interpreter to be invoked. This second interpreter was the same Extended Basic re-compiled to run from a higher memory address and stored in a EPROM. When invoked, the machine was switched into 64k RAM mode and the interpreter copied from EPROM to RAM giving an extra 16K BASIC workspace. (Source : Jon's Dragon Home Page)

The Dragon 64 was sold in various European countries. A slightly modified version was also manufactured and sold in the US by TANO (Technical Associates of New Orleans) from August 1983. They sold the machine under the TANO name for a few months but couldn't compete with the agressive price policy from Commodore, Atari and T.I. All the unsold machine were eventually sold off to a discount store called California Digital.

In 85 Eurohard, a spanish manufacturer, acquired Dragons Data. Then the Dragon 200 replaced the 64 with some minor changes: power-on lights, auto-repeat keyboard... They also also had plans for a 128k Dragon and a MSX Dragon.

Finally, CP-400 from brazilian company Prologica is another Tandy Color Computer clone. It was completely compatible with Color Computer 2. Prologica was indeed specialised in (illegal) cloning of popular micro-computers.

CP stands for Computer Personal. Released in 1984, the CP-400 shows an original plastic case, very similar to the Timex-Sinclair 2068! The calculator type keyboard uses a membrane for contacts. There is a cartridge slot on the right part of the case, accessed via a moving trapdoor.

The CP-400 was released as 16 KB or 64 KB models. But heating/voltage problems on first models led to frequent RAM corruption.

The CP-400 model II was later released, correcting those heating/voltage problems and offering a better keyboard (pseudo mechanical) and 64 KB RAM.

When the MSX systems came in 1985/1986 (in Brazil), sales of the CP-400 started to fall down disastrously. Prologica (and other companies that had launched the TRS Color in Brazil) did not provide necessary support in software and documentation. Even though the Color Computer was successfull in U.S.A., it was difficult to find material for it in Brazil.

== Tandy Color BASIC versions ==

(info from Lee Veal): In reality, the 'dialects' of BASIC on all versions of the TRS-80 Color Computer 1s & 2s were written by Microsoft for Tandy. That includes Color BASIC (CB), Extended Color BASIC (ECB) and Disk Extended Color BASIC (DECB). In fact, with very few modifcations, BASIC programs from an IBM-PC or compatible using Microsoft BASIC could run on a CoCo and viceversa. (The way I know that is that I did it. Some were quite complex graphics oriented programs.) Within one-half K of the beginning the Color BASIC ROM address, there's a character string that reads "COLOR BASIC 1.0(C) 1980 TANDYMICROSOFT". When you fire up a CoCo 1 that has only the Color BASIC ROM, you'll see on the screen
COLOR BASIC 1.0
(C) 1980 TANDY

The authors of Tandy's Color BASIC (Microsoft) left their name in the code, but they left it off the opening display. Subsequent levels of CoCo BASIC (Extended CB and Disk Extended CB) had Microsoft prominently displayed in the opening display. Thus, Color BASIC was quite compatible for obvious reasons with the BASIC that Microsoft develped for the PC. Extended and Disk Extended versions of CoCo BASIC were
even more compatible with Microsoft's BASIC for the PC.

On the other hand, the BASIC dialects contained in computers like the Commodore-64, TI-994A, etc were quite incompatible with any version of Microsoft BASIC.

The BASIC developed by Microware (the developers of the OS-9 operating system and originally Tandy's first choice of a BASIC developer), called BASIC09, was NOT compatible with Microsoft BASIC. BASIC09 is and was a powerful language that compiled to intermediate code but it is more akin to Pascal then BASIC.

== CoCo & CoCo II Double Speed ==

(info from Gary Clouse): The double speed mode was not really accomplished by changing the clock speed. The Synchronous address multiplexor (SAM) chip by default generated memory refresh cycles for the entire address space. The "double speed poke" disabled the refresh cycle for the upper 32k memory address, where the ROM was mapped. Since the ROM was static, it didn't need this and since BASIC spent most of its time in the rom routines, it would appear to nearly double the speed. The flip side of this was that many I/O functions that relied on timing loops would be unusable, such as saving data to a tape. Also if you were using the upper 32k of ram, the double speed poke would wipe the memory.

//(info from old-computers.com)//



===== Links =====

* CoCo Quest Color Computer Games and More! -- http://www.prowler-pro.com/coco/
* Sock Master's Web Page -- http://www.axess.com/twilight/sock/
* www.coco3.com -- http://www.coco3.com/
* Dragon & Tandy CoCo Resources -- http://www.burgins.com/dragon.html
* Dragon, The Archive -- http://www.dragondata.co.uk/
* Graham's Dragon Page -- http://www.grempc.demon.co.uk/dragon/
* The DRAGON Archive -- http://www.dragon-archive.co.uk/
* CP400 -- http://www.cp400.cjb.net/
* CoCo at old-computers.com -- http://old-computers.com/museum/computer.asp?c=91



===== Other Emulators =====

* Color Computer II Emu by Jeff Vavasour -- http://www.vavasour.ca/jeff/trs80.html#coco2




Generated on Sun Jul 19 10:17:28 2009