Hacks, a.k.a. Sins of the past

Last update: 2005-03-14

IN THE PIPELINE...

An update of these pages is long overdue. Some of this dates back to the beginning of 2001. This is what should be coming (most recent first):

Onnama: Yet another implementation of MIPS on an FPGA. Includes a simulator and test cases, VGA graphics, serial, etc..
Hard-C: A C-like language for synchronous parallel programs, mostly inspired by Timogriffer C, with a nod to Handel-C. The compiler generates Verilog and some designs have been tested on Xilinx Spartan FPGA, using Xess' XSA-100 development board and the Xilix ISE WebPack. The linked file is an old snapshot of the development with many features missing.
Yet Another tiny and super light-weight http server library, this one focused on dynamic contents with applets linked into the server.
A basic implementation of the Gated Single-Assignment form, including
- the generation of the GSA from from a CFG (cf. Peng Tu & David Padua, Efficient building and placing of gating functions),
- derivation of the Demand-Dependence Graph, (cf. Daniel Weise et al, Value dependence graphs: representation without taxation), and
- sequentializing this (cf. Bjarne Steensgaard, Sequentializing Program Dependence Graphs for Irreducible Programs).
TFLC: Tiny Functional Language Compiler, translates to native x86 on the fly.
A small AVR Thermostat (I2C, Serial, relay, etc) thermostat-2313-v0.1.tar.gz).
PocketHaskell: A tiny haskell subset compiler and bytecode interpreter. As a tiny proof-of-concept, primes running on a Palm Pilot (alas, GC is not implemented).
A much updated PocketSmartGoban (nee LispGoban)

Programming Language Implementation

Compilers

The Alvilda Optimizing Compiler
Haskell
PocketHaskell, put Haskell in your pocket.
Bits of a Haskell frontend: Haskell Kit?
Coauthor of the haskell-mode for Emacs (one of many haskell-modes available).
Written a bunch of Haskell code, including an implementation of a subset of Haskell for very small machines.
Minor tweaks to Erik Meijers excellent CGI/HTML package. Someone should polish it, extend it and make it a standard library.
Retro-computing: A BASIC (anno 1974) interpreter. For the benefit of a family member.

Hardware

AVR

This nifty little micro controller has got a page of its own. See my getting started with AVR page.

Nascom

Apart from the retro-computing project mentioned above, I've been working on restoring my Nascom II and saving what can be saved of documentation, programs, and tricks. All of it so far can be inspected at The Nascom Homepage. I should mention that I have a rival at MIXTEL.

Misc

Doom

In an effort to bring up DosDoom under Solaris I produced a patch to version 0.61.

LIRC - Linux Infra Red Controller

Worked on improving LIRC (the old LIRC page and older LIRC page is way out of date).

Linux kernel

Wrote the first SCSI driver (aha1542) for Linux v.0.12. I'm no longer the maintainer.
Made the first working version of PLIP for Linux, based on the work of Donald Becker. Added various improvements. Had a first version of an 8-bit PLIP working, but the result was disappointing, thus dropped. I'm no longer the maintainer.

The Game of Go

I have written a large amount of Go code over the years, like an extremely fast and original pattern matcher, an implementation of Bensons unconditional life algorithm, a small and efficient SGF reader and writer (now part of Gnu Go), efficient implementation of basic Go data structures, and several Goban implementations. Most of this in C, but there is also code in Scheme and Haskell. Over the time, more and more of this code will find it's way to this page, but a lot is still hiding in the archives. So far what is available is (in mostly random order):

When I tried to convince General Magic to write a Goban for the MagicLink, I wrote a simple implementation of a goban in C along with a the basis of a UI

Features included: unlimited undo, notion of Ko and komi, and semi-automatic scoring after both Japanese and Chinese rules. Notice, the notion of Ko is only approximate, but handles %99 of real-world ko situation.
A much older project (and in IMHO more interesting) is an implementation of the essential Go structures (groups and liberties), with incremental update and undo. Somebody completely missed the point and put it up under the name tinygo2 the Go ftp server. I have a version here (called IncrementalGo) with an added explanation I gave to the GnuGo group.

Even today, nine years later, I'm reasonable happy with the code, but there are number of things I would change. For one thing I'd change the position representation of use factors of two, eg. X+Y*32 and do away with the ``direction'' array. Also, the handling of Ko in simple-go.c above is much more elegant.
Bensons unconditional life algorithm. Forthcoming (but was seemingly never finished).
MyGoban (for the PalmPilot, works on the XCopilot emulator, but bugs out on the real PalmPilot. I'd be much obliged if someone could help me find the bug).
SGFLib, part of MyGoban and now also part of Gnu Go.
LispGoban 0.1 is a reimplementation of MyGoban in Scheme, using the excellent LispMe by Fred Bayer. LispGoban is roughly at the same stage as MyGoban, but works and has been developed 100% on the PalmPilot, mostly while waiting for other things (like riding the bus, etc).

PalmPilot

I haven't had time to write much for this my little pocket bulge, but I did take the memopad example and turn it into a compilable package. Here's my CompleteMemoPad.zip.
See MyGoban and LispGoban above.

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