SpeedScript 3.0, cartridge edition
This is the SpeedScript word processor for Atari 8-bit computers, adapted to run from cartridge.
The program was originally published in the May 1985 issue of COMPUTE! magazine. The source code used in this version, including comments, is taken from the SpeedScript book, which was also published by COMPUTE! in 1985.
Assembly requires ATasm. Two targets are provided, an Atari DOS executable and a cartridge (.rom) file.
Changes from the published version
There are no major changes in this version of SpeedScript, but there are some minor modifications.
Support for 1200XL function keys
The Atari 1200XL has four function keys, F1-F4, which were mostly used for cursor movement. These keys are mapped to page up/page down/home/end on the TK-II PS/2 keyboard adapter, and have been given SpeedScript functions as follows:
| F key | TK-II key | Function | SpeedScript native key |
|---|---|---|---|
| Shift-F1 | page up | Paragraph up | SHIFT-minus |
| Shift-F2 | page down | Paragraph down | SHIFT-= |
| Shift-F3 | home | Top of document | START* |
| Shift-F4 | end | End of document | CTRL-Z |
* Shift-F3 differs from the START key in that it jumps directly to the top of the document. START moves the cursor to the top of the current page the first time it's pressed, then jumps to the top of the document.
Memory layout
SpeedScript's load address is at $1F00. The originally published version uses parts of $1F00-$1FFF for its startup code, wasting the rest of the space before the custom character set at $2000.
Because code runs from cartridge in this version, all of $1F00-$1FFF
would be wasted if it wasn't used for something else. Fortunately there
is a 256-byte buffer (PRBUFF) that can be moved here instead.
Self-modifying code (and data)
SpeedScript uses self-modifying code for its memory move routines. In the cartridge build, these routines are copied to RAM during initialisation.
The character set is also modified to make non-printing space characters visible. To support this feature, the character set is copied to RAM in the cartridge build.
RESET handling
Cartridges are handled differently from DOS-loaded executables during reset, so the cartridge version has a slightly different reset routine.
Non-disk loading
SpeedScript can use more memory for text and the copy buffer when DOS is not present. The published version tests for cassette load but (for obvious reasons) does not consider the possibility that it was loaded from cartridge; this version instead tests that it was not loaded from disk before enabling this feature.
Building
If you have Ruby installed, the rake command can be used to build
SpeedScript. Otherwise use the following commands:
Cartridge
atasm -r -DCARTRIDGE speed0.m65 -ospeedcar.rom
DOS executable
atasm speed0.m65 -ospeedcar.exe