Open Source Mechanic blog

Story Spectrum prototype

bnitz — Fri, 14 May 2010 18:17:04 +0000

Here is a story spectrum application I’ve been working on. It highlights “purple” prose as well as prose which appears in Shakespeare or Canterbury tales

http://opensourcemechanic.com/stories/submit/

Here is the facebook application I’ve tied to it:
http://apps.facebook.com/textrum/

Fixing a Casio SK-200 Music Keyboard

bnitz — Sun, 28 Feb 2010 23:40:32 +0000

Sometime in the late 1980s or early 90s I bought a Casio SK-200 sampling music keyboard. It has been a lot of fun over the years. I’ve sampled everything from radio static to hulusi’s and harps. The sound quality isn’t brilliant, it’s only 8-bit sampling at 10 kHz, but slightly higher quality than the more popular but older Casio SK-1. I was surprised to learn that 20 years after I bought this keyboard, there doesn’t seem to be a similar “kid-sized” fun sampling keyboard. So I hung onto it and now my kids have fun with it. I think it may have helped encourage my little boy to talk.

The little guy helped break it, but we can fix it and learn how it works.

Boys will be boys, and the little guy loves playing music keyboards with his feet. So one of the black keys was wobbling like a loose tooth.

Who needs C# anyway?

I decided to take it apart and try to epoxy glue the key. Wow there were quite a few screws inside! I read that the SK1 had 4 screws holding the key assembly into the case, this one had 14! Ideally I would replace the cracked key or swap it for a seldom used one at the top of the range, but while white keys are discreet, black keys are grouped, about 10 together on a single piece of plastic. The plastic has exactly the right springiness to make the keys bounce well. The SK-200 is full of discrete electronics, many ICs capacitors, diodes, transistors… all work together to make a robust and wonderful keyboard. Here is a photo of the M4135-MAIM board:

Main logic and sound circuit board SK-200

Here are some of the parts on the M4135-MAIM board

TC4066BP (3)	TC40175BP(2)
5218/4558?(2)	TC74HC174P
TC74HCU04	8517PX204
TC74HC157P2	MSM6294-03
74HCABP(2?)	7416PX204(uPD4464C -15L)
tM6283-02	HD61702A04

The other circuit board has a few small ICs and lots of transistors, capacitors, resistors and diodes. It appears to be the power supply and audio amplifier board.

I took apart a cheap modern keyboard recently and only found one of those ugly black blobs. You can see why keyboards such as this and Casio’s SK-1 are sought after by circuit benders. There are thousands of points where circuit modifications could be made. I found a point where it would be easy to pitch bend and the trick of piggybacking an extra memory bank and soldering the data-select to a toggle switch wouldn’t be too difficult, but I think I’ll leave well enough alone. With this minor repair the keyboard is just as fun as it was in the 1990s and neither Casio nor Yamaha appear to have taken advantage of 20-years of advancements in memory and sampling electronics and given us a higher quality portable sampling keyboard. So this was well worth fixing.

One word of caution, if you do use epoxy, only use enough to fill the crack. You don’t want the stiffness of epoxy to mess up the key bounce. And be very careful you don’t glue the key to the case.

SourceJuicer at Beijing OpenSolaris User’s Group

admin — Mon, 08 Feb 2010 08:11:08 +0000

While I was in China working with the desktop QA team,

I was invited to present SourceJuicer to the Beijing OpenSolaris Users Group/Beijing GNOME group combined meeting. (Thanks Emily and all!)

An engine crosses Malahide rail viaduct testing in progress!

bnitz — Sat, 14 Nov 2009 13:18:42 +0000

I was pleasantly surprised at the quick progress in plugging the breach in the weir and repairing the broken viaduct. Today marked a milestone, it was the first time since the rail problem that I saw a rail car traverse the broken section of track!

14 November 2009, railcar goes across malahide estuary.

O’Reilly’s Beautiful Testing book coming soon!

bnitz — Tue, 20 Oct 2009 14:05:32 +0000

Emily Chen and I coauthored a chapter in an O’Reilly book entitled “Beautiful Testing” which was edited by Adam Goucher and Tim Riley.

Successful software depends as much on scrupulous testing as it does on solid architecture or elegant code. Beautiful Testing offers 23 essays from 27 leading testers and developers that illustrate the qualities and techniques that make testing an art. Through personal anecdotes, you’ll learn how each of these professionals developed ideas of beauty in testing a wide range of products — valuable knowledge that you can apply to your own projects.

The bound version should be available in bookstores in the next few days. The electronic version is already available here:

http://oreilly.com/catalog/9780596159825

Use it or lose it patent legislation proposed in Minnesota

admin — Sun, 13 Sep 2009 20:10:08 +0000

My friend Ron at inventorsagarage.com found this proposed Minnesota legislation which would grant an employee the right to use a patent if his/her employer sits on the patent for too long:

(b) An employer who has a right to develop or utilize an invention or proposal 1.11must make a substantial investment in the invention or proposal within five years of the 1.12submission of the invention or proposal or forfeit all rights and interests in the invention 1.13or proposal to the employee.

I’d wondered about this possibility years ago when I noticed how common it was for an invention to languish in an employer’s defensive patent armory while everyone, including the inventor, is blocked from doing anything with it. There are many reasons for this, for example a company may be operating in a business where the patent might not be applicable. Do we want the idea for a 90% efficiency solar panel or a cure for cancer to sit in a warehouse because the inventor’s day job is at an investment firm or oil company which has absolutely no financial interest in developing the technology? Even when a new patent aligns with a company’s core business, developing the patent might not figure into to the company’s immediate business plan. SEC guidelines force companies to focus on near term (90 day) profits. IMHO this discouraged R&D and may have contributed to the fact that NASDAQ remains below the trend line set in the pre PC, pre-Internet vacuum tube era. The proposed ‘use it or lose it’ law might help uncork some of the innovations which, I imagine are sitting in a warehouse not unlike the one at the end of ‘Raiders of the Lost Ark.’

I agree with Ron that this law has very little chance of passing, but at least it has seen the light of day. If a similar law has passed in another state or country it would be interesting to see if it encouraged innovation. I suspect it would discourage large companies who have every reason to want to maintain their patent hoard, but it would also encourage small start-ups who would take advantage of the wasted IP. Sooner or later we will reach a critical mass of inventors whose creations are kept under wraps and there will be a level of reform somewhere. Then perhaps one day the patent system will live up to the mission of creating an environment that “encourages investment in innovation, and fosters entrepreneurial spirit.”

A carpenter’s explanation of OpenSource

admin — Thu, 10 Sep 2009 20:22:33 +0000

Imagine that you are a shop teacher intending to teach children how to build a wooden footstool:

The shop teacher and the prefab ‘lumber’yard
You go to the lumberyard and ask for some lumber and nails. The guy at the lumber store shakes his head and says, “Sorry, we don’t got that, we only carry EasyDone or NanoHouse products. How about this beautiful prefab bathroom?” You tell him you don’t need a bathroom.

“Perhaps I can interest you in a EasyDone kitchen?” he says.
“Just wood and nails,” you say. Frustration is beginning to show in your voice.
“O.K. then you must choose between an EasyDone or NanoHouse prefab livingroom.”
“I only need wood and nails! Ten penny nails, 2X4s, plywood!”
“We don’t sell that.”
“O.K. then how much is an EasyDone bedroom, I can take it apart and use the wood and nails.”
“$40,000″
“What? That is far too expensive for my budget!”
“It’s fully integrated, painted, the carpet is in place and the bed is even included, it’s ready to go!”
“But it doesn’t do what I need. I’m only going to take it apart and we are going to use the wood in shop class.”
“Wait a minute. Did you say something about taking it apart?”
“Yes! It doesn’t do what we need so I have to take it apart so my kids can rebuild!”
“No, I can’t sell it to you for that, it’s against the law, violates the EULA. Besides, all the joints are epoxy rivet-welded together. You couldn’t possibly take it apart without turning it into sawdust.”
“But I need the raw materials for my students to build a footstools!”
“Go away. I need someone to buy my prefab bathrooms, I have some overstock.”
“Fine!” You say, “I’ll take my business elsewhere.
“There is a NanoHouse prefab garage store down the street.” he offers.
“I’m not interested! And if I ever do need a new bathroom, I’m going to build my own!”
“Oh no you don’t. NanHouse has a patent on those.”

Opensource software is a raw material which can turned on a lathe, nailed together. It can (and must!) be replicated at any stage of customization or enhancement. Therefore, it improves as it is used. If you can’t buy exactly what you want, you can build it or put together the components and configure them to meet your needs. Free software doesn’t eliminate the need for software expertise anymore than raw lumber eliminates the need for carpenters. Free and opensource software (FOSS) is a good fit for education where thousands of schools across the country have similar, but perhaps not identical needs. Ironically, many proprietary software companies have all but abandoned the educational market because of widespread piracy of proprietary software in schools.

When schools had solid federally subsidized budgets for computers, proprietary software running on proprietary operating systems installed on proprietary fat client computers (with a shelf life of little more than one semester), may have seemed a good idea. But this was never an efficient use of funds. For some schools it was the equivalent of buying a pre-fab house for the shop class to take apart and build into footstools and candle holders. Times have changed, educational money has disappeared. Such inefficiencies are now impossible to overlook. In order to give children the best chance of a bright future where they can compete in the global economy, we need find these holes where our government is throwing tax money, and fill them as quickly as possible. It is becoming obvious that to balance their budgets, governments and educational institutions must utilize opensource software and eco-efficient, future-proof, low TCO hardware wherever possible.

ZFS in Apple’s OSX 10.6 Snow Leopard

admin — Thu, 03 Sep 2009 16:46:46 +0000

Storagemojo’s blog has some interesting comments about Apple’s decision to leave the next generation ZFS volume-manager/filesystem out of OSX 10.6 Snow Leopard. I have no idea why they did this. Command line read-only ZFS existed in OSX 10.5 Leopard and an opensource plug-in gave it read write capability. ZFS has proven itself both in saving Apache.org time and headaches after a recent security breech. This is from Apache.org’s incident report:

aurora.apache.org runs Solaris 10, and we were able to restore the box to a known-good configuration by cloning and promoting a ZFS snapshot from a day before the CGI scripts were synced over. Doing so enabled us to bring the EU server back online, and to rapidly restore our main websites. Thereafter, we continued to analyze the cause of the breach, the method of access, and which, if any, other machines had been compromised.
…
What worked?
* The use of ZFS snapshots enabled us to restore the EU production web server to a known-good state.

The consensus seems to be that Sun’s CDDL license wasn’t a factor in Apple’s removing this feature. Sun’s dtrace is already in OSX under CDDL. GPL won’t help here because the OSX kernel is under a BSD license and much of the software and hardware drivers which are able to link to BSD licensed kernel would not be able to live with GPL code. I doubt it is a stability issue, as I’ve mentioned, read-only ZFS has been in OSX for quite some time and many Linux and Windows servers have gone into production based on less reliable and far less scalable filesystems.

Some have claimed that ZFS is only appropriate for large servers. Nothing could be further from the truth. I regularly use it on a tiny Solaris laptop with 2G of RAM. The snapshot, rollback and related boot environment management features are enormous timesavers. Time machine is a typically beautiful Apple GUI built on top of a slow (rsync?) kludge. Merge this GUI with ZFS, and it’s a marriage made in heaven. Snapshots take almost no time or redundant space (Copy on Write), rollbacks are nearly instantaneous. Why wouldn’t artists, writers, musicians and other creative people in Apple’s prime market want instantaneous automatic versioned snapshots of their work?

I don’t know why Apple made this decision. Maybe they want to make their money on a ZFS based storage appliance. In any case, I’m glad BSD and Solaris 10 and OpenSolaris already have ZFS. Even if my Mac or Windows desktop has to rely on archaic HFS+ or NTFS filesystems for another year or two, at least we can push storage out to a more reliable and scalable filesystem running on a modern server-class OS.

28 August Broadmeadows low evening tide

admin — Fri, 28 Aug 2009 21:33:05 +0000

I don’t remember the broadmeadows estuary water level ever being quite so low so close to a high tide. Notice the entire length of the pier is out of the water. Today is partway between a spring tide and neap tide so I wouldn’t expect extremes. The wind was strong out of the west but this is also typical. It struck me that if the channel through the eroded section weir is considerably deeper than the others, eventually the estuary will settle to a lower level.

Malahide rail viaduct before and after photos

admin — Mon, 24 Aug 2009 20:38:12 +0000

Here is a clearer before and after photo. Both were taken from exactly the same spot (with in a couple of feet), with exactly the same kid’s telescope/lens adapter.

Taken on 5 Oct, 2008

Taken on 24 August, 2009

Taken on 5 October 2008

Taken 24 Aug, 2009