brainwagon

If you are like me, you have lots of accounts, and lots of passwords.   Keeping track of them all is a bit of a pain, and it’s increasingly something that you just can’t do with your brain. Several of my accounts now refuse to allow you to use a password which I consider manageable for […]

The ESP8266 is an amazing little processor: cheap and capable and (most interestingly) WiFi enabled. I have some of the older “nodemcu” boards that I got for about $7 each, but there are newer alternatives that include up to 4M of flash memory, and a variety of interesting form factors. I noticed that WeMos was […]

In what quite possibly might be the most boring video ever produced, I recorded myself changing the LCD panel out of my Chromebook. It’s 17 minutes of riveting youtube goodness. Skip down to the bottom if you want to watch. But here’s the story if you’d rather just read a paragraph. My wife bought me […]

I have an odd obsession with small, relatively cheap hardware development boards. Over the last few years, I’ve acquired a bunch of them, from Arduino to Raspberry Pi to BeagleBone Black. I thought it might be nice to just do a short video showing what I have around. So I did. Here’s a little 25 […]

I’ve got a weak spot for cheap, programmable hardware. In my junk drawer I’ve got a collection of Arduinos, Parallax Propellor boards, a couple of STM32 based ARM boards, and several Beagle Bone Blacks and Raspberry Pis. Today, another entry arrived: the WRTnode. I’ve only had it out of the box for a few hours, […]

Previously, I had linked to Rory Mangles’ experiments with relay based computers. He had an incredible build of a relay logic computer called Tiny-8 which used paper as program mamory, inked with a pattern which could be read by photo sensors to sequence the control logic in his computer. I thought it was amazing. But […]

A few days ago, I mentioned that one of my servers had died. I spent some time thinking about how I would replace it. I like having a 24/7 hooked up to the Internet to serve as a file drop and a place where I can use SSH to connect to other devices on my […]

In my home office, I have a machine called “fishtank”. I realized that I first bought it back in 2002, and since then it has been running various flavors of FreeBSD (probably beginning around 4.6 or so, currently running 7.2). At various times I’ve added or upgraded disk drives to it. While a power failure […]

I needed to know the pinouts for various AVR chips and the 6 pin ICSP cable they used. I found this cool little one page sheet that had that, and more. Saved for future reference: Microcontroller cheat sheet.

I’ve always been fascinated by emulation and virtual machines, as well as retro-computing: resurrecting the old machines of my past. I never owned an old CP/M machine, but there are still some neat projects where people construct there own, and simulators like SIMH and YAZE-AG are good software simulators. But what I always wondered was […]

I may have mentioned before, I’m kind of old. One measure of how old I am is the fact that I’ve actually programmed machines that used core memory. Real core memory. Little ferrite donuts on arrays of wires. Some time ago, I remember running across this awesome blog post from “Wayne’s Tinkering Page” which showed […]

I’m old. I learned to program as a teenager in the 1980s. Back then, we learned to program on small microcomputers. These machines weren’t very powerful, but they had a neat feature: they were self-hosted. In recent years, a large variety of small microcontrollers have become popular. Many of these have capabilities far in excess […]

Tom showed me a link to The J1 Forth CPU, a very small processor which is coded in Verilog (only 200 lines!) and can run very fast on existing FPGA boards. It is quite an intriguing design. Forth is an intriguing if somewhat archaic programming language. In the bygone ages of my youth, I experimented […]

I’ve been playing with a BASYS2 FPGA development kit from digilentinc.com, and pondering the world of digital system design. I chose the BASYS2 because of its low price ($70) and because it included a reasonable number of LEDs, switches, a VGA interface and a connector for a PS/2 keyboard. Still, I’ve been looking for other […]

A couple of weeks ago, I noticed a bunch of links to a 16 bit ALU designed to operate using blocks which are defined in the game Minecraft. It got me thinking, and ordered the book that inspired that work. It contains the specification for an ALU which is very simple, and yet surprisingly powerful […]