- This article is about the language for Atari 8-bit computers. Not to be confused with Borland's unrelated Turbo Basic.
Turbo-BASIC XL 1.5 startup screen.
|Original author(s)||Frank Ostrowski|
|Initial release||December 1985|
|Platform||Atari 8-bit family|
Turbo-Basic XL is an advanced version of BASIC for the Atari 8-bit family of home computers. It is a compatible superset of the more common Atari BASIC whose most important feature is the vastly improved execution speed (three times faster). A Turbo-Basic XL compiler was also made available that created binary executables, further speeding up program performance (ten times faster than Atari Basic). Turbo-Basic XL was developed by Frank Ostrowski and published in the December 1985 issue of German computer magazine Happy Computer.
Since their release in 1979, the 8-bit family normally shipped with a version of Atari BASIC on cartridge or built into later machines. This version of BASIC had a number of custom commands that allowed partial access to the system's advanced features like graphics and sound. However, it was also notoriously slow, one of the slowest microcomputer BASICs when running the David Ahl's Creative Computing speed tests. This led to a market for 3rd party BASICs with better performance or more commands. Among them were an official port of Microsoft BASIC sold by Atari, Ken's Super BASIC and a series of BASICs from Optimized Systems Software. There were also several Atari BASIC compilers.
Turbo-Basic XL was a late entry to this list, first published in December 1985 in source code form. It was unique in that it came in both interpreter and compiler versions. It included code to take advantage of the expanded memory available on the XL series machines, and later XE series. This meant that it could not run on the original 400/800 systems, which led to a port known as Frost BASIC (or FrOst) that was tied to Atari DOS 2.0. A number of ports to different versions of DOS were available.
Among the extra features of Turbo-Basic XL, added to ATARI BASIC, are the following:
- enhanced sound and graphics commands
- more flexible I/O commands, including disk access
- structured programming constructs
- simple debugging facilities
- Ahl, David (November 1983). "Benchmark comparison test". Creative Computing. p. 260.
- Fetzer, Ron (1985). Expanded Turbo-BASIC XL Documentation (PDF).
- Atari 8-bit pages – Scans of the Turbo-Basic XL listing and Turbo-Basic XL compiler listing from Happy Computer Magazine. Also lists the new commands added to the language.
- TurboTari – An extended BASIC emulator (based on Turbo-Basic XL) and 6502 emulator/Atari architecture emulator all in one. Currently unfinished.