2011

Mon, May 23

<23:47 EEST> Back at the school for a week of teaching. I feel like I have a ton of energy left from the past week of intense hacking. I am looking at a rather heavy week of 28 lessons, which is probably my record so far, although at this time of the year things are not so serious any more.

Fri, May 20

<16:53 EEST> This entry begins on Friday the 13th, which turned out particularly fortunate for me. A week, a song and a dozen digital designs later I finally have the time to sit down and write about it.

On Friday, my FPGA board finally arrived, a Nexys2 that I had ordered from the States. For the first time in Finland I had to file a customs declaration, and it was somewhat tricky to find the correct code for this product class. This was done earlier that week, and as I got the hardware on the 13th, I was already busy working on a song that I had started on the previous day.

However, playing with the FPGA turned out a really nice intermission from the sound work. I could rest my ears and do something at least as geeky, while using mostly different parts of my brain. Except, of course, when making audio circuits. It would have been nice to be able to integrate these two projects, and indeed people have made devices like guitar effects on FPGAs, but my skills are not quite there yet. I was pleased, nevertheless, to be able to play my own song through a PWM DAC I had just assembled.

One of my main interests in FPGAs is to accelerate certain computations in hardware, and an important reason for doing the PWM was to learn about serial interfaces. I used pyserial on the computer end, having converted the sound file with sox. So far I have learned a basic way of sending data from Python and reading back the results of calculations.

As for the new song, read all about it on a dedicated page with lyrics. It has been a rough week of endless tweaking, learning to sing once again, and making a pantyhose pop filter. I am glad to be able to leave this 7-year project behind at last.