mikal – Page 59 – Made by Mikal

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…

Beer fridge controller 0.1

Post author:mikal
Post published:December 21, 2009
Post category:Arduino

On the weekend I picked up a 220 liter beer fridge for $20. Its in really good condition (ignoring some minor rust in the freezer section), and the only real problem with it is that the thermostat doesn't work leaving the compressor on the whole time. Doug suggested that instead of just buying a new thermostat, we should build an arduino fridge controller. I'm not really a hardware guy, but once Doug had pointed me at the Dallas 1820 1-Wire temperature sensor, and lent me some resistors, it was pretty easy to pull the software side together. Note that this version doesn't actually do any of the compressor control -- it simulates that by turning a LED on. The compressor stuff has been delegated to Doug and will be mentioned later. You can see that the circuit is in fact really simple. There is a LED to simulate the compressor (with a resistor), and then the 1-Wire temperature sensor (with another resistor). The code is pretty simple too. Here's my latest fancy version: #include <OneWire.h> #include <DallasTemperature.h> #define COMPRESSOR 13 #define ONEWIRE 2 #define HIGHTEMP 4 #define LOWTEMP 3 #define SLEEP_SEC 10 // 220L Kelvinator is 85 watts #define COMPRESSOR_WATTAGE…

Saturn’s Children

Post author:mikal
Post published:December 16, 2009
Post category:Book

I had trouble getting really into this book, although the story was interesting. I guess its mostly the Gibson-esque descriptions of a future world with plenty of assumed knowledge. However, I found the descriptions of the failed Mars missions deeply satisfying, and would love to see those covered in more detail. However, the story gets better as you go along, and I found the second two thirds of the book to be really good. It probably helped that I have an engineering background, because some of the descriptions are quite technical.

Bolo!

Post author:mikal
Post published:December 11, 2009
Post category:Book

This book is a return to the short story collection style of Bolo book, with all of these short stories being written by David Webber. Unfortunately, most of these stories are not new: "Miles to Go" and "A brief technical history of the Bolo" appeared in Bolos 3: The Triumphant, and "The Traitor" and "A Time To Kill" appeared in Bolos 4: Last Stand. Only "With Your Shield" is new to me in this book. That one new story is a good one, although I think it helped that the Melconians had already been introduced in other short stories. I enjoyed it, even though there was only about 90 pages of new content in this book. [isbn: 1416520627]

Last Human

Post author:mikal
Post published:December 11, 2009
Post category:Book

This is Doug Naylor's first solo book, after the breakup of his Red Dwarf partnership with Rob Grant. This book deviates pretty wildly from the plot line developed by the TV series, although it does use some of the ideas from the series. Often these ideas are used in such a different way that it would be annoying if you were expecting a novelization of the series. This book also has more characters die than is normal for Red Dwarf, and I felt that often the deaths were unneeded. Apart from that this was a good quick read. [isbn: 0140143882]

The Dragonlover’s Guide to Pern

Post author:mikal
Post published:December 9, 2009
Post category:Book

I bought and read this book for the short story "the impression", which is ok but not fantastic. Overall the book isn't really my thing -- its mostly a potted history of Pern and a nearly exhaustive coverage of the various weyrs, holds and craft halls that inhabit the planet. To be honest, I'd rather learn that stuff as I read the series, instead of reading a summary. Overall I think this book isn't particularly great, although its nice to have read the short story at the right time in the sequence. Having just read Dragonsdawn, there are also some inconsistencies which grated a little (the use of HNO3 for example, and how much knowledge of the Oort cloud the survey team had string to mind as examples). [isbn: 0345412745]

Dragonsdawn

Post author:mikal
Post published:December 8, 2009
Post category:Book

This book was similar to the other McCaffrey books I've read in that it felt like it lost its way in the middle for a bit. I'd been looking forward to this book for a while, because I really wanted to see the science fiction aspects of colonizing a new planet and developing a genetically engineered dragon explored. While this book did that, I don't think it focused on the elements I wanted to -- there was little discussion of the mechanics of either of these things, and instead a big sub plot about a jewel thief which was irrelevant and annoying. Overall, this book was ok, but not fantastic. [isbn: 0345362861]

Bolo Strike

Post author:mikal
Post published:December 4, 2009
Post category:Book

There is a planet populated by humans which has been isolated for many years. In that time, aliens have come to rule the planet and treat the humans as slaves. Its pretty clear that they need liberating, right? What if you trash the planet in the process? What if they actually have the ability to defend themselves (something you didn't adequately prepare for)? Pretty standard bolo fare, and fun for all the same reasons as the others. I enjoyed this book, even if I am not a better person for having read it. [isbn: 0743435664]