Jon Simpson

CSCS: Bringing it all together

7 Feb 2005 — cscs, pda robotics, scheme, xml-rpc

Ok, so I seem to have taken a short hiatus from writing weblog entries recently, but I figure its time to start writing about interesting things again. There have been two CSCS meets since my last entry, both of which have focused on getting results with the PDA+Brainstem+Servo combinations that we’re using. Both sessions felt quite productive, and it felt like we worked through some of the issues that had been holding back development on the various fronts we’d been working with the kit on.

To summarise the last two Thursday sessions, we’ve having interesting problems getting the platforms talking to the Brainstem, which now seem to have been solved. The long version involves connecting all of the equipment together and watching as random things happen and the equipment generally doesn’t behave as it should. For future reference, the Brainstem was rapidly flashing its green LED when powered up, then not producing a rapid heartbeat pulse as the documentation would indicate. However, what the documentation didn’t make clear was that this heartbeat was also indicative of an active RS-232 connection to the device, an issue that was clarified by Acroname’s (rather helpful) telephone support. It also turned out that an orange indicator on the serial adapter for the Brainstem should have been lit to indicate a serial connection, which hasn’t been the case when we’ve connected the kit together before.

Various attempts at obtaining a successful connection to the brainstem followed, involving a null modem cable and some Dell workstations, but nothing seemed to work out before the end of the session. Rob reported back success the following day using a USB to Serial connector to communicate with the Brainstem, which seems to leave us in quite a good position to kick off the next CSCS session on Thursday. I have suspicions as to why the Zaurus hasn’t been picking up a serial connection involving serialctl and other fun things, but those will have to wait for further investigation.

As a note, I currently have the following equipment:

Notable absences from this list of kit include a CF reader (did this go to anyone?), the second Zaurus PSU, The power cable for the Battery Charger, Zaurus Manual & Original CD-ROM and probably some other stuff I don’t remember at this point. Collecting together all of the kit may be a useful thing to do to get it all back together. (At this point, I really wish I’d done the original kit distribution list in more detail.) If you know where other pieces of kit are, feel free to leave a comment below/mail me/do $RANDOM_ACTION or whatever suits you.

Coming slightly off the topic of brainstems directly, Rob also give an interesting introduction to PocketPC development & its current state. C# looks like quite a nice language to program in overall, with its Java-like syntax and the UI code for a Hello World app seemed quite simple. Requiring Visual Studio is a slight show-stopper, although I think Matt brought forward the idea of using mono to compile the bytecodes.

From the direction we’ve been taking recently, the sessions have been mostly hardware based, so I haven’t seen much occam recently, but word says the Transterpreter is pushing along well toward release, along with its shiny new logo and website. The slinker still gives me visions of a certain spiral toy for progressing down sets of stairs, but maybe I just prefer that to attempting to visualize the slinker’s real task.

Planet CSCS is up and running, although I don’t actually think its called that (maybe a suggestion to forward to the appropriate department). Works out well for keeping tabs on what people are up to and the relevant weblogs that follow CSCS. I guess we’ll see if Wordpress cooperates with the Scheme RPC handler for pushing updates there when I post this, a piece of code documented on Matt’s weblog. I was highly impressed with the ease of development displayed by Scheme as a CGI, and intrigued as to the language. Perhaps something to look into with the InfiniteAmountsOfFreeTime™ that should coming to me any day now.

I think that pretty much concludes the happenings of CSCS over the last two weeks and related items. As always I seem to write in spates of long entries every now and then, a habit I should really break, as it makes these entries hard to read conveniently. (Also the rambling style of starting at the top and working through by figuring out related issues to each point contributes to making these posts overly long).