The microbee's BASIC evolved from the 12K DG680 CPU Microworld Z80 Extended Basic Version 2.1t.
This particular version was released on tape and takes an eternity to load (nearly 7 minutes- Worse if there are load errors.).
It contains support for the TCT PCG Graphics and its joysticks but no support for the DG680's sense port buttons quite odd considering most PCG owners made hand controllers with joysticks and game buttons.
The core engine was written for an 8080 but this version includes additional Z80 instructions and the use of its index registers.
It has keywords such as SET, RESET, POINT, NORMAL, FLASHING, INVERSE, PCG, SPEED, HIRES, CURS, JOYST & DGOS.
To run the BASIC one needed to have at least a 16K RAM card located at 0000-3FFF and 2K of DG680 RAM located at D800-DFFF.
The BASIC essentially occupies 0000-2EFF with about 1K scratchpad leaving about 3K user programs which start at 33C0 (Not dissimilar to microbee BASIC's 08C0) but to make better use an additional 16K RAM memory card from 4000-7FFF would increase the user program space to 19K.
In 1981, version 2.7 was released with its code slightly restructured, tuned more towards the Z80 and introduced the AUTO and PLAY functions.
Located at 8000, it was designed use as a ROM set for the MW2516 S100 EPROM Card and being a step closer to the production of microbee.
Rather than retaining the "Extended Basic" moniker it was called "Level II" in line with Tandy's marketing tactics.
This particular version was released on tape and takes an eternity to load (nearly 7 minutes- Worse if there are load errors.).
It contains support for the TCT PCG Graphics and its joysticks but no support for the DG680's sense port buttons quite odd considering most PCG owners made hand controllers with joysticks and game buttons.
The core engine was written for an 8080 but this version includes additional Z80 instructions and the use of its index registers.
It has keywords such as SET, RESET, POINT, NORMAL, FLASHING, INVERSE, PCG, SPEED, HIRES, CURS, JOYST & DGOS.
To run the BASIC one needed to have at least a 16K RAM card located at 0000-3FFF and 2K of DG680 RAM located at D800-DFFF.
The BASIC essentially occupies 0000-2EFF with about 1K scratchpad leaving about 3K user programs which start at 33C0 (Not dissimilar to microbee BASIC's 08C0) but to make better use an additional 16K RAM memory card from 4000-7FFF would increase the user program space to 19K.
In 1981, version 2.7 was released with its code slightly restructured, tuned more towards the Z80 and introduced the AUTO and PLAY functions.
Located at 8000, it was designed use as a ROM set for the MW2516 S100 EPROM Card and being a step closer to the production of microbee.
Rather than retaining the "Extended Basic" moniker it was called "Level II" in line with Tandy's marketing tactics.