μblog: engineering from the trenches

1.) Install the GNU Privacy Guard for your system

2.) Download and install Enigmail (Thunderbird extension)

3.) Restart Thunderbird

4.) Click on the Encryption icon and fill in the information (generates keys, starts keychain, etc)

5.) Enjoy a bit more privacy!

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Today, I found the Faraday, Helmholtz, Kelvin and Newcomb lectures from the Harvard Classics, 1910 edition. I was reading the William Thomson, Baron Kelvin of Largs, lecture on the wave theory of light, and came across this passage:

“The school system seems to be very admirable, and I hope the teaching of the metrical system will not be let slip in the American schools any more then the use of globes. I say this seriously: I do not think any one knows how serious I speak of it. I look upon our English system as a wickedly brain-destroying piece of bondage under which we suffer.”

The lecture was delivered on 29^th September, 1894, at the Academy of Music in Philadelphia.

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I found this German site today that aimed to test what the minimum hardware requirements for running Windows XP really were. They got it down to 7Mhz with an 18MB of ram (system info lies a little bit.) Important to note that XP did not install on a 486, probably due to difference in memory controllers, but 8MHz Pentium is not too much of a step up.

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Over the past week, I have been pretty busy with data analysis and designing a field controller for a colleague. The field controller is a device which accepts a program voltage and sets up an electric field in a recording chamber which is proportional to the program voltage regardless of the chamber conditions (meaning solution conductivity changes.) The field controller also maintains optical isolation where the output stage runs off batteries. Most of the field controller electronics are voltage-feedback op-amps with multiple feedback paths to give it the function, with an LOC110 optocoupler from Clare to give the isolation. This is a pretty nifty IC with two matched photodiodes to give a feedback control and a large bandwidth (>200KHz) so it has plenty of useful applications. Below is the datasheet and an app note dealing with isolated amplifier design.

( LOC110.pdf ) ( AN-107.pdf )

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After talking to the manufacturers of the eeprom programmer, we both decided that I should send it back to have it checked/replaced, so no rewritable roms for a week or two. In the mean time, I found a copy of Super Mario Brothers 3 at a local shop. I also decided to open the NES and follow the connector re-conditioning directions for the best experience. Now it’s time to get the power up and win the game.

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A long time ago I found a small script somewhere that fetches http://www.livejournal.com/stats/latest-img.bml (dynamic file containing recently added pictures on livejournal) and parses it so that you get to see the picture and the post it was placed in. For a long time, this was on my work server, but I decided to move it here, since I now have legitimate hosting! Anyhow, it has become the most accessed page on microblog.routed.net (due to a redirect from the previous url) so I figured that the rest of you wanted to see too: latest images from livejournal (image list is computer generated, some images may not be in good taste and may not be work-safe.)

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Some people say that instant noodles are the ultimate lazy person’s food, which may have indeed been the case until the invention of the rice-maker. To prepare for moving, I bought a rice cooker today so that I could try it out while I was in the DC area and could exchange it if it did not work too well. I settled on this “MICOM-FUZZY” from Zojirushi. The features are fast cook time (20 minutes) and extended “keep-warm” time which should be in the neighborhood of one day. The capacity for this unit is 5.5 “cups” (where one cup is 0.18L and a US cup is ~0.25L) which roughly translates to 2600 kcal of energy assuming standard, long grain, white rice. Given that washing the rice can be considered optional (assuming you are super lazy) so all you need to do is to put in the rice, add some water, push a button, and wait a little bit and voila, you have enough food (which lacks most nutrients other than energy) for one day. Sounds a bit quicker than having to cook noodles for breakfast, lunch and dinner!

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After spending all those hours writing LabView code to program Atmel 8051 chips as well as EEPROMs, I now have access to a universal DIP programmer. This thing is supposed to be able to program almost any kind of chip (memories, PLD, MCU) that is dip and can be programmed and even some other chips through in-circuit programming capabilities. With this in hand, I can either modify my MMC1 (Nintendo memory mapper v1) and try loading a MMC1-based NES rom onto it or try to find a MMC3 cartridge somewhere and put a MMC3 game on it. (According to Kevin Horton, the only MMC2 video game was Mike Tyson’s Punch-Out and the higher end games are more complicated to design re-programmable cartridges for.) Maybe there is an easier way to get a copy of Super Mario Brothers 3? (If you have it and don’t mind giving it to me, let me know!)

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Some time ago, I wrote a small program to run from cron that would send me a sms if I had unread emails (after checking your non-SSL imap server) from people in a whitelist file, people like my colleagues and my boss. Since it has proved to be useful to me, here it is! System requirements are at least P4 or AMD64 with 1gb of available ram and 1.5GB disk storage.

( txt-mail.tar.gz )

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I have been kicking around the idea of designing a 386 based system sometime this summer, so I am looking at references and looking at what a minimal system would be. Something that had a serial console and could run an old dos or a small Linux/BSD would be nice. Below is a reference design document and a 386sx datasheet. (both from Intel)

( 386sx.pdf ) ( 24072501.pdf )

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