3 May 2003

ProForth for DOS is a powerful, comprehensive Forth system for PCs with 80386 or higher processors. This MPE Forth implementation uses MPE’s own royalty-free DOS Extender to provide a 32-bit Forth running in 32 bit protected mode. All memory accesses and data items are a full 32-bits wide - with double and floating point numbers even more accurate. ProForth for DOS allows PCs to be used for large real-time control applications and embedded PC hardware.

Full DOS file and shell/spawn support

EGA/VGA 16-colour mode graphics support

Direct screen drive with pop-up and tiled text windows

Full message-passing software scheduled multitasker

Support for 80387 or 80486DX IEEE hardware floating point

Helps with debugging and understanding code

Build smaller, more secure applications

Virtual code model allows even larger, self-configuring applications

Write words using full 80386/7 instruction set

TED text editor and FRED screen file editor supplied

Simple mechanism to build auto-running applications

Compatible with all other MPE Forth systems

Interrupt driven comms, single step debugger, faster compilation, more numerical input formats, more examples, grahics examples, enhanced DOS extender, enhanced floating point, plus many other detail improvements.

MPE has introduced a new pricing system for ProForth for DOS. We have also introducing a new set of services designed to provide MPE clients with services that are unavailable from larger software houses.

DOS Operations

Full file system - open, close, read, write, create, delete files, etc. - plus support for DOS Shells, spawning other applications (both protected and real mode) and other functions through the integrated 386/387 assembler. ProForth for DOS also includes its own heap manager giving dynamically allocatable and de-allocateable linear memory - no more segments when allocating memory.

Screen Control

All functions drive the screen direct by default. This may be directed to other devices through the vectored I/O system used by ProForth for DOS. Support for text windows is also built-in - tiled windows, pop-up windows, with or without borders, headers, etc. Windows may be opened, closed, moved, reopened, etc. at will, both interactively and under program control. BIOS and ANSI support are also included.

Graphics

ProForth for DOS includes graphics functions compatible with 16 colour modes of EGA and VGA video adaptors. The functions include lines, circles, arcs, boxes, polygons, flooded areas and background colours. Different line types may be selected and text may be mixed on the screen.

Multitasking

A full co-operative multitasker is built-in. This may be used to run several tasks at the same time, passing messages between them, responding to events, and controlling each other.

Floating Point Maths

A full hardware floating point word set is built-in. This directly uses the coprocessor for 64-bit IEEE floating point operations. Support is provided for formatted number input and output. All the usual mathematical functions are provided as Forth words, using all the facilities of the NP.

Decompiler

A structured decompiler is built-in for understanding and debugging high-level Forth words. This decompiler lays out the definition being decompiled so that the structure can be understood.

Debugger

A single step debugger allows Forth words to be traced recursively, with a running display of the data stack.

Headerless words

A mechanism is built-in to allow some or all of the application words to be compiled without headers. This makes the code both smaller and more secure.

Binary overlays

Binary overlays are a mechanism by which pieces of compiled code may be loaded and unloaded from the system as they are needed. Prime examples are the assembler and the Forth screen editor. These are both binary overlays which are only loaded as they are needed. The assembler is a good example in that it may be loaded in order to compile one or more new definitions, and may then be unloaded from memory so that the application does not include an entire assembler.

Source code support

ProForth for DOS includes both TED, a text file editor, and FRED, the MPE Forth screen editor. Using these editors, or others such as a BRIEF compatible editor (for which Forth-specific macros are supplied), either or both formats of source code may be edited and compiled into ProForth for DOS applications. Most of the source code for ProForth for DOS is supplied as text files. New in version 2.2 are the debugger and interrupt driver serial comms.

Turnkey application generator

ProForth for DOS includes a mechanism for saving-off turnkey applications. These are binary files saved off as .EXP files ready for the MPE royalty-free DOS Extender to load and run. These may then be bound with the DOS extender itself in order to make stand-alone applications for distribution. The binder utility is supplied with ProForth for DOS and is included in the price - ProForth for DOS version 2 is the only package you need to develop and ship DOS protected mode applications.

Macro Assembler

The system includes a full 386/387 macro-assembler. This may be used to code routines requiring faster execution, or interrupt routines, or for any other reason. The assembler supports both the traditional MPE syntax (postfix) and default addressing modes (direct) and the standard Intel/Microsoft syntax (prefix) and default addressing modes (immediate). It is therefore easy to use this assembler whatever your background. The assembler also supports both USE16 and USE32 segments.

Source code compatibility

ProForth for DOS is source-code compatible with other MPE Forth systems such as ProForth for Windows and PC PowerForth Plus.

DOS Extender

The integral royalty-free DOS extender is compliant with all other protected-mode interfaces such as Windows, DPMI, and VCPI, as well as being suitable for standalone use. Applications written in ProForth for DOS will also behave well in a system with or without memory management tools. The DOS extender also makes ProForth for DOS ideal with embedded purchase. The DOS extender supports the traditional DOS INT 21H interface, with most functions extended to 32 bit registers. Additional support is provided for handling 16/32 bit calling and interrupt installation.

Example code

The system is supplied with a range of useful and interesting example source code. This includes conditional compilation extensions, a simple debugger, execution profiling extensions, and many classic computer-science problem solutions in Forth. User contributed code includes an LED simulation and multitasking examples.