Offete Enterprises

Hello, I am Dr. Chen-Hanson Ting. I have been programming in Forth for almost 40 years, and had accumulated a large collection of stuff which might be useful to those who are interested in this language and its many applications. These materials are now available digitally. Before I get the PayPal account working, you can send me a request at I will then email the material, and send you an PayPal invoice.

eForth Systems

New! ceForth 2.3 on Visual Studio and espForth 4.4 on Arduino.

I had always looked for low-cost microcontroller kits to teach people how to program in Forth. eForth is a very simple Forth language model Bill Muech designed in 1990. Over the years, I ported eForth to many microcontroller kits, as they were getting cheaper and more powerful. I had lots of fun with them, and I enjoyed seeing others having fun (and making useful products) with these kits as well. eForth captures the essence of Forth, as an universal programming language for small, embedded systems. Earlier eForth systems were mostly for 8 bit and 16 bit microcontrollers. Later I moved it to more powerful 32 bit microcontrollers like MIPS and ARM. These eForth implementations are distributed with source code and substantial documentation.

Forth Books

After I learnt a Forth system, I always tried to document it so I could teach other people how to use it. So I wrote about figForth, polyForth, F83, F-PC, and cmForth. When Win32Forth came along, I gave up, because it was too large and too complicated. I then focused on developing eForth for microcontrollers. After retirement, I cleaned out the books off my shelves. People still asked for them, so I converted them to pdf files. They include Systems Guide to figForth, Inside F83, and Footsteps in an Empty Valley.

CPU Worshop

In Early 1990, Chuck Moore designed a 20 bit microcontroller MuP21 for me. I tried to extend his design to build 8 bit, 16 bit, 24 bit, and 32 bit microprocessors. I had used VHDL to design these Forth microcontrollers and tested them on FPGA’s. A 16-bit processor eP16 and a 32-bit processor eP32 were published. I ported eForth to these chips for design verification. In 2016, we ran a CPU Design Workshop in Silicon Valley Forth Interest Group, and I used designs of Intel 8080 and DEC PDP1 as exercises. It was interesting that eForth was used here as test benches, which were much more difficult to design than CPU themselves. What I wanted to demonstrate is that you can design your own CPU, and get it verified on FPGA. Forth is not just a programming language, it can be design into CPU hardware, and it can help you debugging your own CPU prototypes.

Forth Thoughts

  • Forth Is a List Processor
  • Laws of Computing
  • eForth Tutorials
  • Right to Assemble