This page was last modified 14:54, 10 October 2021 by Mars2000you. Based on work by Gdx and Kanima.


"X-BASIC" aka "MSX-BASIC KUN", "KUN BASIC" or "TURBO BASIC" is a run-time compiler for MSX-BASIC that is commonly used to speed up existing MSX-BASIC programs and create demos and games.


There are three versions of this compiler, all officially released on cartridge, but hacked binary versions were also available:

  • 1.0 with only the 'Basic' instructions CALL RUN, CALL TURBO OFF and CALL TURBO ON
  • 2.0 with some improvements and 3 new instructions '#C, '#I, '#N
  • 2.1 especially optimised for MSX Turbo R computers

Version 1.0 is included in the MSX2 Talent TPC-310 computer as TURBO BASIC.

A slighly modified version of X-BASIC 2.0 is included in the MSX2+ Sanyo PHC-70FD and PHC-70FD2 computers with internal disk drive(s). It comes with an extra instruction, CALL BC that initializes KUN BASIC.


According the used version, X-BASIC adds 3, 6 or 7 instructions to MSX-BASIC.


  • For the instructions that begin with CALL, you can replace CALL by _ (the underscore character). A space is not required after this character.
  • Sometimes CALL TURBO OFF and CALL TURBO ON were renamed by the coders of the MSX scene in their products (games, demos, disk magazines, tools).
Instruction Generation Versions Remarks
'#C MSX2 2.0 - 2.1
'#I MSX1 2.0 - 2.1
'#N MSX1 2.0 - 2.1
CALL BC MSX2+ 2.0 Only on MSX2+ Sanyo with internal disk drive(s)
CALL RUN MSX1 1.0 - 2.0 - 2.1
CALL TURBO OFF MSX1 1.0 - 2.0 - 2.1
CALL TURBO ON MSX1 1.0 - 2.0 - 2.1


Pages in category "X-BASIC"

The following 2 pages are in this category, out of 2 total.