Advanced Video Attribute Terminal Assembler and Recreator

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The Advanced Video Attribute Terminal Assembler and Recreator (AVATAR) protocol is a system of escape sequences occasionally used on bulletin board systems (BBSes). Its basic level was designed explicitly as a compression of the much longer ANSI escape codes, and can thus render colored text and artwork faster over slow connections. Even when the terminal didn't understand it, the data on disk could use the AVATAR format and so take up less space. Note: A much more comprehensive protocol was proposed, but never gained much support.

The term escape sequence has more than one meaning, depending on context:

A bulletin board system or BBS is a computer server running software that allows users to connect to the system using a terminal program. Once logged in, the user can perform functions such as uploading and downloading software and data, reading news and bulletins, and exchanging messages with other users through public message boards and sometimes via direct chatting. In the middle to late 1980s, message aggregators and bulk store-and-forward'ers sprung up to provide services such as FidoNet, which is similar to email.

ANSI escape sequences are a standard for in-band signaling to control the cursor location, color, and other options on video text terminals and terminal emulators. Certain sequences of bytes, most starting with Esc and '[', are embedded into the text, which the terminal looks for and interprets as commands, not as character codes.

The basic protocol is defined by FidoNet technical standard proposal FSC-0025. [1]

FidoNet is a worldwide computer network that is used for communication between bulletin board systems (BBSes). It uses a store-and-forward system to exchange private (email) and public (forum) messages between the BBSes in the network, as well as other files and protocols in some cases.

Avatar was later extended in late 1989 to AVT/0 [2] (sometimes referred to as AVT/0+) which included facilities to scroll areas of the screen (useful for split screen chat, or full screen mail writing programs), as well as more advanced pattern compression. These extensions were not convertible directly into sequences understood by existing ANSI terminals but instead mirrored extra facilities available in the IBM PC BIOS.

Avatar was originally implemented in the Opus BBS, but later popularised by RemoteAccess. RemoteAccess came with a utility, AVTCONV that allowed for easy translation of ANSI documents into Avatar helping its adoption.

RemoteAccess

RemoteAccess is a DOS Bulletin Board System (BBS) software package written by Andrew Milner and published by his company Wantree Development in Australia. RemoteAccess was written in Turbo Pascal with some Assembly Language routines. RemoteAccess began in 1989 as a clone of QuickBBS by Adam Hudson. RemoteAccess was released under the shareware concept in 1990 and became popular in North America, Europe, UK, South Africa, and the South Pacific. Initially the main advantage over QuickBBS was its ability to run multiple nodes under Microsoft Windows, Quarterdeck's DESQview and OS/2. RA could also operate over a network or even a combination of network and multitasking operating systems to provide multiple "nodes per station" capabilities.

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References

  1. ↑ FSC-0025 - AVATAR proposal at FidoNet Technical Standards Committee
  2. ↑ FSC-0037 - AVT/0 extensions
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