BBC BASIC
BBC BASIC is a programming language developed in 1981 as a native programming language for the 6502 -based Acorn BBC Micro home computer, primarily by Sophie Wilson . It is a version of the BASIC programming language adapted for a BBC UK computer education project .
BBC BASIC is based on the older Atom BASIC (for the Acorn Atom ) and extends the traditional BASIC with named procedures and functions, REPEAT-UNTIL loops and IF-THEN-ELSE structures, inspired by the COMAL programming language . The interpreter also includes instructions to control BBC Micro's four-channel audio output and its high-resolution screen output.
One of the outstanding features of BBC BASIC was an inline - assembler , processor-specific, which allowed the user ( 6502 -) to write programs. This assembler was completely integrated in the BASIC interpreter and could access its variables. This allowed developers not only to write directly in assembly code, but also to write BASIC programs that in turn generated assembly code at runtime. So you could also write simple compilers in BASIC.
The appearance of the Acorn Archimedes computer series (1987) and the associated RISC OS also led to a further development of the BBC BASIC, here called Basic V, which allowed it to achieve a language standard that raised it to the level of a modern, functional language similar to Pascal. Innovations are u. a. an extension of the loop concept using WHILE, a case differentiation with CASE-OF-WHEN-OTHERWISE-ENDCASE, a library concept using LIBRARY, error handling at procedure level, flexible data transfer using LOCAL DATA and a RESTORE, which can be used absolutely and relatively, as well as the possibility of local Arrays and direct array operations, e.g. B. in order to be able to perform matrix multiplications, for example for 3D graphics. There is also improved support for sound and graphics as well as mouse input.
BBC BASIC has been ported to many different computer platforms and is available e.g. B. under CP / M, for the Amstrad NC100 and NC200 pad computers, the Cambridge Z88; but there are also versions for DOS and Windows and many more. With Brandy BASIC there is a freely available and easily portable version under the GPL.
The source code of the current version has been available at ROOL under an Apache license and including documentation since 2018.
With RISC OS Pico, a Raspberry Pi can be booted directly into a BBC BASIC; ideal to implement device controls or maker projects quickly and easily, or to simulate a "home computer on speed" according to a classic pattern.
Individual evidence
- ↑ http://www.bbcbasic.co.uk/bbcbasic.html
- ↑ https://sourceforge.net/projects/brandy/
- ↑ https://www.riscosopen.org/content/downloads/cvs-access
- ↑ http://www.riscos.com/support/developers/bbcbasic/index.html
- ↑ http://www.riscos.com/support/developers/manual_index/basic.html
- ↑ http://www.riscos.com/support/developers/basicv/index.htm
- ↑ https://www.riscosopen.org/wiki/documentation/show/Software%20information:%20RaspberryPi:%20RC5%20RISC%20OS%20Pico