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Welcome to the STM8 eForth Wiki!
Here you'll find information on the following topics:
- A gentle step-by-step introduction to using STM8 eForth
- STM8S Value Line Gadgets documents supported boards (e.g. thermostats, breakout boards)
- Example Code for inspiration
- Technical documentation, e.g. start-up code, interrupts or programming tools (please refer to the sidebar)
- STM8 Programming tips with the focus on SDCC (assembler, C-compiler and simulator)
Some topics, mainly community discussions, are easiest to find by clicking on Pages in the sidebar. The Issue tracker and the Release notes also contain a lot of additional information.
TG9541/STM8EF is an improved version of Dr. C.H.Ting's STM8 eForth for the STM8S Discovery. With the kind permission of the original author it provides a permissive FOSS license.
Thanks to innovations and contributions from experienced and skilled members of the Forth community STM8 eForth has found its place as a tiny but very usable embedded Forth system. Thanks a lot :-)
The STM8 architecture has some properties that make it very well suited for interactive embedded Forth systems. Experienced Forth practitioners have found STM8 eForth to be very usable, even when compared with open-source µC Forth systems which have a richer feature set, or that target more powerful hardware (good examples are AmForth for AVR8 and MSP430, noForth for MSP430, Mecrisp for MSP430, or Mecrisp-Stellaris for Cortex-M).
STM8 eForth aims to be a very lightweight interactive Forth for low-end STM8 µCs with a good "feature-to-binary-size" ratio:
Carefully designed embedded control features (e.g. background and idle tasks, interrupts, RAM and Flash operation), e4thcom support, and a framework approach, turn STM8 eForth into a powerful tool, even for low-end STM8S Low Density devices (for an example see W1209 data logging thermostat). Also supported are STM8S Medium and High Density devices, as well as some STM8L devices.
This project has the following goals:
- provide an easy to use Forth kit for STM8 µCs
- provide board support for common low-cost Chinese control boards
- maximize the product features * free space (for fun and profit)
- engage with the Forth community on core, development environment, libraries, and applications,
With respect to Forth standardization, STM8 eForth takes a practical approach: when gaps in the original code have to be filled, inspiration is taken from Forth-79, Forth-83, FIG-Forth, ANS-Forth or later standardization attempts.
The GitHub repository has a sister project eForth for Cheap STM8S Gadgets on Hack-a-Day. There are other projects HaD projects and GitHub repositories that use STM8 eForth code (some or listed in STM8 eForth Example Code).
eForth is a well documented implementation of a basic Forth by Bill Muench and Dr. C.H. Ting.
eForth is based on a set of about 30 Forth core words written in assembly or C instead of using meta-compilation from another Forth system. Higher level words, e.g. for interpreter and compiler, are written in Forth. eForth was designed with portability in mind there are implementations for many µCs and µPs.
Originally eForth was a DTC Forth, some later implementation, like STM8EF, use the STC model.
Forth, the programming language that does things differently, is the work of Charles H. Moore and others.
There are many on-line Forth resources. Some of the most notable are:
- Leo Brodie's books Starting Forth, and Thinking Forth
- scans of the magazine Forth Dimensions (indexed)
- some issues of Forthwrite, the FIG UK Magazine
- publications by the German Forth-Gesellschaft e.V. (mostly German, some in English).