On FORTH and a Friend

FORTH is a programming language with a lot of both interested and interesting users and implementers. Unbeknownst to you, your anti-lock brake controllers and fuel-injectors could be running by FORTH, and even if they aren’t, surely other critical parts of your vehicle are running on it, or diagnosed and maintained with it, or both.

The curious thing about the language is that its manifestation in this reality demonstrated how a single programming language could be both highly perform-ant and highly expressive. This is rare and uncommon. Today, no language achieve this feat. To consider that FORTH achieved it on limited computers, a long time ago, adds further wonder and respect for this delightful language. If you haven’t even taken at least a single look at it, then you should grab your copy of whatever you call hardware systems, along with the latest copy of gforth, to write hello world and play with the stack a little bit. It is interesting how much expressivity and power you can get out of a little computer system using this neat language. The language isn’t the most important thing though; it is the people.

When choosing a Scheme distribution, someone quipped that “When you choose one, you aren’t choosing a interpreter, so much as, you are choosing the a community”. This is true. Since it was tradition to implement your own FORTH interpreter, you could join a lot of different communities. The common traits among all of them were humans who could think for themselves, optimize at every level of the implementation (both software and hardware), and have a lot of fun doing it. One of those people was a best friend of mine named Bruce Langenbach.

Bruce passed away this year. His LinkedIn profile is still up; though I put in a request to retire it. For some bizarre reason, he never mentions FORTH on this resume. At Bear Automotive Service Equipment he used it to run all of the equipment (Bear sells automobile maintenance systems). The cool thing was that FORTH didn’t just run the equipment, it was also the operating system, code-editor, and debugger, all implemented and executed on-device. All of the REPL-joy that people blog about today was there long ago on little computers (which are somewhat dismissively called “micro-controllers” when in reality they are just computers like any others). That was a really, really fun job.

Bruce told me about it all of the time. It was the most fun job that he ever had. Anyone knows that with any job you have ups and downs. It is especially hard though when your first job is your best one. Fortunately he was investing in and exploring non-programming related forms of employment and expression. The neatest stuff was the encaustic painting.

Encaustic painting, using my simple understanding of it, uses layers of hot wax. It is beautiful, and, is a beautiful form of expression. Bruce was working on integrating LEDs and Arduino-systems with the canvas and the art. I loved hearing about it and was really, really looking forward to seeing what he was ready to share.

If he had been able to finish his work, he surely would have done it on FORTH. This implementation in particular says all of the right things, in spirit, intent, and implementation, and surely would have been a great place to start.


colorForth is a redesign of [Forth] for the 21st century. It also draws upon a 20-year evolution of minimal instruction-set microprocessors. Now implemented on modern PCs, it runs stand-alone without an operating system. Applications are recompiled from source with a simple optimizing compiler.

It is the child of Chuck Moore, the creator of Forth.

Why you might want to learn FORTH

You may or may have not heard about the programming language Forth, but if you have heard about it, you are very likely to have heard about it from some very happy, passionate Forth developers!
The best advocacy/introduction/tutorial I’ve ever read about Forth is located in the beginning of source code for this Forth interpreter!
After reading this, it is hard not to get excited about the programming language Forth.

Unlock Forth on the OLPC XO

A week or so ago I ended up on “Luke’s Weblog” reading an article about Forth on the OLPC XO.
The OLCP Wiki has got Forth Lessons for everyone to enjoy. Forth is a pretty neat language!
You may have noticed that although access to the Forth shell is explained on this page, it doesn’t work. The reason can be two-fold. First, you can only access the Forth shell if the firmware security is disabled. Second, on newer machines you access the Forth shell by hitting the escape key at boot time.
This page explains how to gain access to the Forth shell on machines that have got the firmware security enabled (G1G1 owners, that means you). You need a developer key to unlock your firmware, the request takes less than 24 hours to be fulfilled. Please read the page closely (disable-security twice!) and heed their advice of disabling firmware security (you can always enable it later).