Made by Mikal – Page 57

Thinking about arduino as a prototyping platform

Post author:mikal
Post published:December 30, 2009
Post category:Arduino

So, I've mentioned in earlier posts about arduino projects that I consider the arduino to be a prototyping platform, and a damn good one at that. Hack a day seems to think of it in similar terms. It was really Doug who got be thinking in this direction with the initial PCB design for the fridge controller project, which includes space for an Atmega CPU right on the PCB, thus eliminating the need for a relatively expensive arduino board to be permanently consumed. So I started to wonder how hard it would be to build a simple arduino replacement board. It wouldn't need the complicated USB hardware, as you could program the Atmega on a full arduino board before installation. It would just need a time source, perhaps a LED, and a voltage regulator. You can see in the picture above a version I quickly whipped up on a breadboard to prove this is possible. I didn't bother with a voltage regulator in this version, and the wires off on the right go off to a power source. This quickly turned into a PCB prototype board design, which has a voltage regulator, and exposes all of the arduino digital pins…

Colony

Post author:mikal
Post published:December 30, 2009
Post category:Book

The Times is wrong about this book. Its not "cruel, cynical and very funny", its cruel and cynical for sure, but it lacks hope and is overall just depressing. I certainly didn't feel it was funny. Its strange, I loved the Red Dwarf series, and this book is very similar. I think the problem is that this book lacks all the hope and charm of the Red Dwarf books and TV show. Its a book entirely comprised of Rimmers, and that's hard to take. [isbn: 0140289755]

Arduino with the kids: Cricket Noise Door Bell

Post author:mikal
Post published:December 29, 2009
Post category:Arduino

When I was a child, I had a doorbell at my bedroom door to ward off uninvited guests. My six year old, Matthew, has always been pretty enthused about building things, and so he wanted to give an electronics project a try. I thought this would be a good project to start out with for the kids, because its relatively simple, and there is a tangible result at the end (you press a button and something happens). Matt liked the idea. Because this project involved a fair bit of soldering, it turns out that Matt spent most of his time taking photos of the work, although we talked about what was happening at each step. I need to think harder about how to get him involved in the construction process -- I think that will be easier once the bread boarding stuff from ebay arrives. The design is relatively simple. I took the sample debounce circuit (a button, 10k resistor) and software and ran that first. Then we put a peizo buzzer across pin 13 and ground. That meant that with the sample software we had both a light and a noise when you pressed the button. Unfortunately, the pin…

The Robot City, Robots and Aliens Series

Post author:mikal
Post published:December 27, 2009
Post category:Book

This series follows on from the Robot City series set in Asimov's Foundation Universe but written by other authors. Overall that first series was weak, and I think the same is true for this series as well. There are a few here that are better than the others, but I'd only recommend this series for those who are obsessed with Foundation universe completeness. 1989: Isaac Asimov's Robot City: Robots and Aliens: Changeling by Stephen Leigh 1989: Isaac Asimov's Robot City: Robots and Aliens: Renegade by Cordell Scotten 1990: Isaac Asimov's Robot City: Robots and Aliens: Intruder by Robert Thurston 1990: Isaac Asimov's Robot City: Robots and Aliens: Alliance by Jerry Oltion 1990: Isaac Asimov's Robot City: Robots and Aliens: Maverick by Bruce Bethke 1990: Isaac Asimov's Robot City: Robots and Aliens: Humanity by Jerry Oltion

Isaac Asimov’s Robot City: Robots and Aliens: Humanity

Post author:mikal
Post published:December 27, 2009
Post category:Book

This book is actually the best one of the two robot city series (Robot City and Robots and Aliens). Unfortunately I had to wade through 12 not very good books to find it, and its still not stellar. I'd recommend giving both these series a miss unless you're obsessed with completeness in Asimov's Robot universe.

Caliban Series

Post author:mikal
Post published:December 26, 2009
Post category:Book

These are books written in Isaac Asimov's Foundation Universe by Roger MacBride Allen. These books are actually better than the Robot City Series, in that they at least explore issues that Asimov himself touched upon. 1997: Caliban 1998: Inferno 1999: Utopia

The Robot City Series

Post author:mikal
Post published:December 26, 2009
Post category:Book

These are books written in Isaac Asimov's Foundation Universe by other authors. They don't progress the overall plot of the Foundation series, they just use some of the concepts and characters to tell similar stories. The books in the series are: 1987: Isaac Asimov's Robot City: Odyssey by Michael P Kube-McDowell 1987: Isaac Asimov's Robot City: Suspicion by Mike McQuay 1987: Isaac Asimov's Robot City: Cyborg by William F. Wu 1988: Isaac Asimov's Robot City: Prodigy by Arthur Byron Cover 1988: Isaac Asimov's Robot City: Refuge by Rob Chilson 1988: Isaac Asimov's Robot City: Perihelion by William F. Wu To be honest these books aren't fantastic and I wouldn't recommend them unless you're trying to get exhaustive coverage of Asimov's Foundation universe.

Foundation’s Friends

Post author:mikal
Post published:December 26, 2009
Post category:Book

I was excited when I found Foundation's Friends the other day, because I thought I'd read all the Foundation books and did not know that this one existed. It is an anthology which celebrates Asimov's 50 years as a science fiction author, and each author takes their own approach to the Foundation universe. The stories are: The Nonmetallic Isaac or It's a Wonderful Life (Ben Bova): not really a short story, more of an inspection of the impact that Asimov's non-fiction writing has had on the world. Strip-Runner (Pamela Sargent): set after The Naked Sun, a young female strip runner meets Elijah Bailey. The Asenion Solution (Robert Silverberg): a pretty standard science fiction short story. Murder in the Urth Degree (Edward Wellen): I haven't read any of the Doctor Urth mysteries, so to be honest this story seemed pretty weird. Trantor Falls (Harry Turtledove): covers the fall and sack of Trantor at the end of the first Galactic Empire. This one is pretty good, and in keeping with the overall Foundation universe. Dilemma (Connie Willis): Asimov deals with some three law robots. Maureen Birnbaum After Dark (George Alec Effinger): I find Maureen's character to be superficial and annoying. This story…

Beer fridge controller 0.3

Post author:mikal
Post published:December 24, 2009
Post category:Arduino

Last night Doug made up the first cut of the PCB for the beer fridge controller mentioned in previous posts, and we fitted the arduino to it. There wasn't much in the way of software changes, apart from changing the pin that the compressor runs on. You can see here that we've mounted both the arduino and the Ethernet shield onto the PCB -- this is just temporary until we get the PCB right. The black rectangle at the front right is a 240 volt capable relay, and the thing behind it is a 240 volt transformer which is capable of powering all the electronics on the boards. In the final PCB we wont need the arduino at all -- just the Ethernet shield and the atmega 328 from the arduino. However, that didn't work out this time around because of problems getting the Ethernet socket to fit nicely. Its clearer on this picture of the other side of the board: See how we had to cut a hole in the PCB for the socket? That took out some of the pin holes for the atmega, and a few tracks. Its not a big problem because we're going to iterate…

Beer fridge controller 0.2

Post author:mikal
Post published:December 23, 2009
Post category:Arduino

Further to yesterday's post about the beer fridge thermostat replacement, I've been hacking on ethernet support for the controller. This is handy because I'd like to log the temperature and compressor state over the network, because I'm hoping that can be used to make calculations about the thermal mass of the contents of the fridge, and therefore derive how much beer is actually in the fridge at any given time. Because the controller also supports more than one temperature probe, I'll also add more 1-Wire temperature sensors around the house so I can determine important things like if its hot in the outside world. The code is currently experiencing some bloat in the binary size, mainly because the ethernet library and the sprintf implementation are quite large. I'll have to think more about that. Here's the current code: #include <enc28j60.h> #include <etherShield.h> #include <ip_arp_udp_tcp.h> #include <ip_config.h> #include <net.h> #include <websrv_help_functions.h> #include <OneWire.h> #include <DallasTemperature.h> // Temperature sensor and compressor setup #define COMPRESSOR 9 #define ONEWIRE 3 #define HIGHTEMP 4 #define LOWTEMP 3.6 // 220L Kelvinator is 85 watts #define COMPRESSOR_WATTAGE 85.0 #define SLEEP_SEC 10 OneWire oneWire(ONEWIRE); DallasTemperature sensors(&oneWire); unsigned long runtime = 0, chilltime = 0, last_checked = 0, this_check…