Household Tips: Reviving a Dead Laser Cutter.

Not long ago, I happened to come across a very cheap and heavily used CO2 Laser Cutting Machine, made by Full Spectrum Inc. About 1K USD, including curbside delivery from across the continent.  I also bought the traditional water chiller, air compressor, exhaust manifolds, etc:

The junk seller promised an intact tube, and indeed there was:
Naturally, [...]

Posted in: Cold Air, Distractions, Hardware, NonLoper by Stanislav 6 Comments

The Alert Reader.

The following is a conversation I recently had with an alert and inquisitive reader. It has been redacted for brevity; handles/names/irrelevant things have been removed. Some text has been turned into links to relevant material.
Anyone still reading this page for reasons related to its original purpose is encouraged to read this; it may help to [...]

MicroWriter Redux.

I have decided to publish some of my “archaeological” work from last year on Cy Endfield’s MicroWriter.  The original objective was to produce a cycle-accurate emulator.  I do not currently have the free time to complete this project, so I will post my results here for anyone who might care to pick up the torch. [...]

Kalman Reti, the Last Symbolics Developer, Speaks of Lisp Machines.

Boston Lisp Meeting; June 28, 2012.
Update: Here’s a mirror of the film. The Google copy appears to have been censored.

Engelbart’s Violin

Computing pioneer Alan Kay tells us that a computer is “an instrument whose music is ideas.” This seems like a beautiful metaphor, until you realize that we have somehow ended up in a world where the profession of musician is nearly unknown.  To continue with this analogy, let’s imagine that you were a [...]

March 2012 Update

Loper’s I2C controller is working.  The SPD ROM on the DDR2 RAM stick attached to the Xilinx ML-501 board is read correctly.  The video controller is working (though not feature-complete.)  The DDR2 SDRAM controller is still under testing, as is the cache SRAM controller.  The gigabit Ethernet controller is not yet complete.
I should probably say [...]

Stierlitz Example: Memory-Mapped I/O to a Character LCD

Here is a somewhat dumb example of the kind of thing one can do with Stierlitz.  Let’s say that you have some memory-mapped I/O ports in your system architecture, which you would like to test without having a working CPU design of any kind loaded into your FPGA.
The Xilinx ML501 board includes a Tianma-TM162, which [...]

Posted in: Cold Air, Hardware, Lisp, LoperOS by Stanislav 4 Comments

For Your Eyes Only

Rumor has it that a well-known industrial giant will soon attempt to bring head-mounted displays back into fashion.
One ought to remember that, for a number of reasons, they were never really “in” fashion to begin with.  To my knowledge, every single one ever marketed fell into one of the following categories:

Military toy, priced somewhere in [...]

Stierlitz, the Fearless, Driver-Less Bus Analyzer.

The tool described in this post may be helpful to other ab initio machine-architecture developers.  If any exist.  The rest of Loper will remain in my private code repository, because it is not a collaborative project.
Meet Stierlitz [1], perhaps the world’s strangest bus analyzer.  For basic use, it requires no software at all on the [...]

Posted in: Cold Air, Hardware, Lisp, LoperOS, Progress by Stanislav 2 Comments

Cypress EZ-Host Firmware Development Under Linux.

Progress has been slow, because I have been otherwise occupied for quite some time.  Slow, but not entirely still.
Since turning Loper OS into an ab initio CPU architecture project, I have been using Xilinx development boards for prototyping.  For the past year —  an ML-501.  The FPGA toolchain itself is (grudgingly) Linux-friendly, but those for [...]

Posted in: Cold Air, Hardware, LoperOS, Progress by Stanislav 20 Comments