Posts Tagged ‘Rockets’

WTPA v0.95 Assembled, Other Nerd Biz

Thursday, November 6th, 2008

The nerd-biz has been thick since my last post — Chicago-based rocketry’s own Ignignokt ate peroxide in New Mexico, I finished making a bunch of art pieces / circuits for my man Cory (who is putting them in a show this month at Team Gallery which opens on November 13th — those of you in New York should definitely crash it), I made some fancy LED illumination for a furniture firm here in Chicago, and we have a new President who I’m told has a Twitter account. As of now I’m currently playing hooky on an Embedded radio project which is due soon for another buddy of mine.
Sadly this means that I’ve been a big slacker w/r/t WTPA, but I did manage to assemble the HOT NEW circuit:

In this photo if you look closely you can see that the board is up and running, drawing a reasonable amount of current and turning on the power light. It’s back to a pricey and involved Hello World, but I’m excited to get the code up to speed soon. Truth be told I’m about ready to flip out and just finish this project since it’s been all up in my free time for half a year now, and I can’t wait to get on to some NEW electronic instrument design. I just got this great book and it is both inspiring and incredibly useful — it makes me remember why I fell in love with the humble emitter follower all those centuries ago :-)

PS: Here are some random hard-earned nuggets of electronic design arcana I discovered during that artsy Video Game Controller-Controller job:

  • On the AVR, DORD flips the order in which the bits are _received_ as well as transmitted.
  • Surprisingly I’ve seen the AVR (mega164p) run at 20MHz more often than not at 3.4vDC. I only saw one misbehavior that looked like an oscillator burp.
  • The INVALID pin on the Max3221 is useful as hell. The TSSOP-16 package gives me more bridged pins than anything else I’ve ever soldered, however.
  • Serial Terminal Dumps — use “script -a LogFile” then “term” or “kermit” or “screen” or whatever. You can also do this with Minicom and the escape-L command. Or “term” and “tee”. And you will be totally buggered if you try this on a Mac b/c of its bizzare “cooked” serial drivers.
  • A weird thing about doing SPI with the Playstation One: You can send an ACK pulse TOO FAST after serial byte exchanges with some games, and the console will abort the transfer. I had to add nops in my interface. Also — this is only true for some games (EA Sports, are you listening?)
    • Corrollary: Some games (specifically EA sports games) will bail on you and pause if you have a bad controller exchange during play — I think this is an effort on the developers to help the player in case they pull a controller out in the heat of competition, and it makes sense, but MAN was it annoying to me and required a lot of workaround.

WTPA v0.95 Boards Arrive

Friday, October 17th, 2008

There is some spiritual sense of wholeness, some cosmic teleology that makes me feel thoughtful about posting pictures of a circuit called “Where’s The Party At” when it’s Friday night.

Like if somehow all the drunk, attractive people on Milwaukee Avenue could see the current in these traces they wouldn’t go to a 4am bar, because they would already have been there. Or something. I can’t decide whether this parable is supposed to be more like the two young fish meeting the old fish in the river, or the young bull and the old bull seeing all the cows from the top of the mountain. Some kind of middling-stinky animals appreciating time-and-reality type business is what I suppose I’m going for here.

*Ahem* So:

The next revision of PCBs are in! You’re looking at the Version 0.95 WTPA “barebones” boards. One thing I really like about Advanced Circuits is those sharp (and handy) fluorescent notepads they give you when you order a board. It tickles my hope for nerd-success: I used to really have to hoard them — not so long ago it took Very Serious Consideration before ripping off one of those bright, rare leaves to write “Call Mom” or something. Now I can pretty much paper my walls with them. Feels good. Before you know it I’ll have a cummerbund!

I can already see it’s going to be one of those nights, so down to business: These boards are necessary because they’re the last rev before I order the hundreds of PCBs and many thou of parts I’ll need for the real production release. Hopefully these guys are pretty close to perfect. Parts are already on their way from Digikey and Mouser and should be here next week. I’ve got an OS to re-write in the meantime — I’ve been learning a lot about the GNU Linker for some other projects and as a result my MCU code is getting a lot more pretty looking, and a little more clear (to me anyway) w/r/t how GCC’s optimizer thinks about it. Practically speaking I doubt I’ll have the OS re-written in the next couple weeks: I’ve been nuts making a Playstation version of Beat The Champ (also #8 here) which needs to be done in short order and, and just got a fancy interior design related project which of course ought to be done like yesterday, too. Of course the X-Prize Lunar Lander Challenge is next weekend and I plan to get good and drunk and watch my friends at TrueZer0 put a whoopin’ on the guy that wrote Doom.
Finally, my crappy electronic music project is playing (using WTPA even) next Friday at the Hideout with my old buddies in Parts and Labor.