Pandora rules!

I continue to be amazed by how great Pandora is. (There was an article about Pandora in last weekend's NYT magazine - interesting read.)

As evidence of its awesomeness:



I've always suspected that there was a lot of great music out there that I didn't know about, and Pandora has confirmed this theory in spades.

Gus Hamilton Hovemeyer

Born Friday, Oct 9th at 11:21 AM, 7 lbs, 15.7 oz.


This is why I haven't posted anything recently :-)

Eclipse galileo software update is ****ing slow!

Why does the latest version of Eclipse (Galileo) take so long to install software updates?

It seriously takes 5-6 minutes to install a package that has already been downloaded! There is no disk I/O, and only about 10% CPU utilization! What the **** is it doing?

OK, it's not actually 5-6 minutes, but it sure ain't fast.

TortoiseSVN weirdness

I had tremendous difficulties today trying to connect to a svn+ssh repository on a Solaris server using TortoiseSVN on a Windows client. I kept getting error messages of the form "network connection closed unexpectedly" with no explanation. Fortunately, I was able to find a workaround (see below).

I think the problem was bash on the server: every non-interactive ssh login was printing error messages to stderr, and for whatever reason TortoisePlink (the ssh client included with Tortoise) could not deal with these. I am not absolutely certain that this explanation is correct, but here is my reasoning, based on trying various combinations of svn and ssh clients on Windows:

1. cygwin svn / cygwin ssh: worked fine (the error messages were visible, but ignored, and the svn operation worked)
2. collabnet svn / TortoisePlink: "network connection closed unexpectedly"
3. collabnet svn / cygwin ssh: worked fine!

I worked around the problem by changing my login shell to /bin/tcsh on the Solaris machine: that made the error messages go away, I guess because bash is installed incorrectly on that machine.

Once I changed my login shell to eliminate the error messages, the latest version of Tortoise (1.6.5) was able to connect to a remote svn+ssh repository.

Now, if I could somehow get back the hours I spent figuring this out... :-)

Dick Morris on YCP

There is an interesting post on Dick Morris's blog about York College of Pennsylvania, and how YCP has kept costs down while maintaining educational quality:

http://www.dickmorris.com/blog/why-is-college-so-expensive/

I think his general point---that most colleges and universities spend huge amounts of $$$ on things that contribute nothing to the education that students receive, and that these costs are ultimately borne by students---is well taken.

74hc163 symbol/device for Eagle CAD

The 74xx-us library for Eagle CAD does not include support for the 74xx163 counter IC. I made a small library which includes it. The library is here:

http://faculty.ycp.edu/~dhovemey/DHH-74hc163.lbr

Only the DIL16 package (a.k.a. DIP or PDIP) is supported. I have not tried creating a board using the library, so caveat emptor.

74hc163 problem - solved

My colleague Greg figured out why my 74hc163 counter IC wasn't working. The problem was not the counter - it was the 74hc04 IC I was using as an ersatz logic probe. With the 150 Ohm resistors I was using, the LEDs were consuming more current than the 74hc04 could supply.

Greg gave me a ULN2803A peripheral driver IC which is capable of sinking 500 mA per pin, which is more than ample for lighting an LED. I modified my "logic probe" circuit, and now everything is working nicely. As a side-benefit, I now have 8 inputs rather than just 6.

A picture:


Now the 74hc163 properly rolls over from 1111 (15) to 0 (0000). Next experiment - cascading two 74hc163's to make an 8-bit counter.