highaltitude.log.20080128

[00:05] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[00:05] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[00:14] edmoore_ (n=edmoore@pomegranate.chu.cam.ac.uk) left irc:
[00:14] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[00:25] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[00:32] flowolf (n=flowolf@87.13.187.42) left irc: "Leaving"
[00:36] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[03:13] Laurenceb (i=Laurence@dhcp38-046.sthughs.ox.ac.uk) left irc:
[06:24] zorton (i=zorton@216-67-48-247-rb1.fai.dsl.dynamic.acsalaska.net) left #highaltitude.
[06:50] borism (n=boris@194.126.108.2) joined #highaltitude.
[07:51] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[08:07] edmoore_ (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[08:07] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc: Read error: 104 (Connection reset by peer)
[08:17] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[08:26] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[08:37] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[10:02] Simon-MPFH (n=simon@phantom.mpfh.co.uk) joined #highaltitude.
[10:04] edmoore_ (n=edmoore@pomegranate.chu.cam.ac.uk) left irc: Read error: 113 (No route to host)
[10:18] flowolf (n=flowolf@87.13.187.42) joined #highaltitude.
[11:28] jgw (n=jgw@unaffiliated/jgw) left irc: Remote closed the connection
[14:31] borism (n=boris@194.126.108.2) left irc: Read error: 145 (Connection timed out)
[14:37] hj1980 (n=hj1980@5ac26e50.bb.sky.com) joined #highaltitude.
[14:37] <hj1980> hi guys/girls!
[15:10] chewy (i=564018b2@gateway/web/ajax/mibbit.com/x-670cf419fed52d33) joined #highaltitude.
[15:10] Nick change: chewy -> chewyy
[15:10] <chewyy> hi
[15:10] <chewyy> anybody there ?
[15:11] <chewyy> meh :(
[15:12] <chewyy> natrium42: it's smealum
[15:13] <chewyy> (if you come by soon :P)
[15:14] <chewyy> bbl
[15:14] <chewyy> (15 minutes)
[15:23] edmoore (n=edmoore@chu-gw.churchillcambridge.co.uk) joined #highaltitude.
[15:31] chewyy (i=564018b2@gateway/web/ajax/mibbit.com/x-670cf419fed52d33) left irc: Read error: 110 (Connection timed out)
[15:35] edmoore_ (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[15:43] edmoore (n=edmoore@chu-gw.churchillcambridge.co.uk) left irc: Read error: 110 (Connection timed out)
[15:46] chewyy (i=564018b2@gateway/web/ajax/mibbit.com/x-51d823803212f19c) joined #highaltitude.
[15:46] <chewyy> hi again ^^
[15:46] <chewyy> ..
[15:47] <chewyy> (sorry, stupid cla3
[15:47] <chewyy> classmates
[15:47] <chewyy> 120.
[15:47] <chewyy> (nevermind)
[15:47] <chewyy> fuck
[15:47] <chewyy> ...
[15:47] <chewyy> (seriously, just... don't look)
[15:47] chewyy (i=564018b2@gateway/web/ajax/mibbit.com/x-51d823803212f19c) left #highaltitude.
[15:47] smealum (i=564018b2@gateway/web/ajax/mibbit.com/x-ef2d02af86dbd07c) joined #highaltitude.
[15:48] <smealum> (this time it's really me, sorry for disturbing...)
[15:52] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[15:52] <smealum> hey kc0wys_
[15:53] <smealum> please, tell me you're there
[15:53] Action: smealum feels lonely
[15:59] smealum (i=564018b2@gateway/web/ajax/mibbit.com/x-ef2d02af86dbd07c) left irc: "http://www.mibbit.com ajax IRC Client"
[16:02] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[16:05] flowolf (n=flowolf@87.13.187.42) left irc: "Leaving"
[16:09] edmoore_ (n=edmoore@pomegranate.chu.cam.ac.uk) left irc: Read error: 113 (No route to host)
[16:09] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[16:09] <hj1980> hey
[16:11] <kc0wys> hi
[16:21] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[16:27] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[16:31] <hj1980> hey
[16:32] <hj1980> how are you kc?
[16:32] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[16:33] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[16:34] hj1980 (n=hj1980@5ac26e50.bb.sky.com) left irc:
[16:41] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[16:42] willo (i=willosof@giardia.exploit.no) left irc: Read error: 104 (Connection reset by peer)
[16:42] willo (i=willosof@giardia.exploit.no) joined #highaltitude.
[16:52] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[17:03] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[17:04] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[17:09] Laurenceb (n=Laurence@fwnat-pub-1.physics.ox.ac.uk) joined #highaltitude.
[17:09] <Laurenceb> hi all
[17:12] <natrium42> hey Laurenceb
[17:12] <Laurenceb> hello
[17:14] <natrium42> what's new?
[17:15] <Laurenceb> working away on my project
[17:15] <Laurenceb> I've got a noise problem :(
[17:15] <natrium42> :S
[17:15] <Laurenceb> sending a 3.3v signal into a 5v avr
[17:15] <natrium42> i hate those problems
[17:15] <Laurenceb> its picking up noise
[17:16] <Laurenceb> and as the voltage is low that shows up as a signal
[17:16] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[17:16] borism (n=boris@ip76.cab5.lsn.starman.ee) joined #highaltitude.
[17:16] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[17:17] <natrium42> i see
[17:18] <natrium42> know any EEs?
[17:19] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc:
[17:20] <Laurenceb> I'm asking on #electronics
[17:25] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[17:29] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[17:29] <natrium42> perhaps you should have used a PCB...
[17:33] Action: Laurenceb gets out the scope
[17:33] <Laurenceb> arrg there these very short spikes all over the shop :(
[17:35] <Laurenceb> about 1500mv high
[17:35] <Laurenceb> grr this is what happens when you use 300mhz processors
[17:37] <Laurenceb> well theres several changes I can make to the board
[17:37] flowolf (n=flowolf@87.13.187.42) joined #highaltitude.
[17:37] <Laurenceb> and as the noise is such high frequency, a bit of filtering would help
[17:38] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[17:38] <Laurenceb> If I clip a few crock clips across to tie gnds together it goes down a bit, so that encouraging
[17:39] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[17:50] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[18:01] borism (n=boris@ip76.cab5.lsn.starman.ee) left irc: Read error: 145 (Connection timed out)
[18:02] Hiena (n=Hiena@81.93.195.181.datatrans.hu) joined #highaltitude.
[18:03] <Hiena> Good evening!
[18:06] <Laurenceb> hello
[18:09] <Laurenceb> ok.. I've put in a low pass filter
[18:10] <Hiena> What frequency?
[18:10] <Laurenceb> 300khz
[18:10] <Laurenceb> its to remove the voltage spikes
[18:13] <Hiena> What kind of signals?
[18:14] <Laurenceb> serial
[18:14] <Hiena> 115 kbps?
[18:14] <Laurenceb> nah 9600
[18:15] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[18:19] <Hiena> Isn's little bit high the 300k for it? I rather set to 64 kHz or something like that. Over the 10*f almost no matter for the digital signal the cut frequency.
[18:22] flowolf (n=flowolf@87.13.187.42) left irc: "Leaving"
[18:24] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[18:25] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[18:32] flowolf (n=flowolf@87.13.187.42) joined #highaltitude.
[18:32] jgw (n=jgw@unaffiliated/jgw) joined #highaltitude.
[18:36] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[18:36] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[18:44] Laurenceb (n=Laurence@fwnat-pub-1.physics.ox.ac.uk) left irc: Read error: 104 (Connection reset by peer)
[18:45] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[18:49] <Hiena> How much is the average measuring container weight? And how much is the aviable lift?
[19:05] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[19:06] neontube (n=davemart@neontube.plus.com) joined #highaltitude.
[19:08] <natrium42> Hiena, rocketboy made a nice excel table for the kaymont balloons --> http://wiki.ukhas.org.uk/guides:balloon_data
[19:08] <natrium42> once you plug in all values, it shows how high you can go
[19:11] <Hiena> Ok. I'm just thinking to desing a flat panel, open-source, glider/liftingbody.
[19:11] <natrium42> ah, neat
[19:12] <neontube> evening all
[19:16] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[19:17] <Hiena> But the problem is the weight. With this method, have to create at least 400g heavy glider for 400-800g payload, except if you have an access to aome carbon naterial.
[19:17] prpplague (n=dave@mail.americanmicrosystems.com) joined #highaltitude.
[19:19] <prpplague> natrium42: ping
[19:23] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[19:24] neontube (n=davemart@neontube.plus.com) left #highaltitude.
[19:32] <prpplague> anyone have some reference material on shielding electronics near-space/space usage?
[19:34] <Hiena> Two layer tin foil is enough.
[19:35] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[19:35] <Hiena> Until, you not goes over 80km, it's not a big problem. But it could cause a problem, if it's loose.
[19:35] <prpplague> Hiena: ahh interesting
[19:36] <prpplague> Hiena: what kind of shielding is need for over 80km ?
[19:36] <Hiena> I lost a modell due the metallic surface caused interferece.
[19:38] <prpplague> Hiena: not sure i understand that statement
[19:39] <Hiena> Not so much. Below the ionosphere, the radiation is kind of same as here. If you have EMC sensitive equipment, you could try to shield it. But such shielding could cause much more trouble as protection.
[19:39] <Hiena> I means, interference.
[19:40] <prpplague> Hiena: ahh
[19:40] <prpplague> Hiena: what about operations above? i.e. satellite operations
[19:43] <Hiena> I dunno. I really have no much information. I saw the gold foil which used as the cover material, and also saw some radiation hardened ICs, but thats all.
[19:43] <prpplague> ahh
[19:47] <prpplague> hmm
[19:47] <prpplague> looks like everything but the cpu comes with a rad-hard parts
[19:51] <Hiena> Yup.
[19:51] <prpplague> Hiena: i bet they have one, just don't advertise it
[19:53] <Hiena> The shielding?
[19:57] jcoxon (n=jcoxon@host86-129-62-157.range86-129.btcentralplus.com) joined #highaltitude.
[19:57] <Hiena> Needn't so much. At the geostac. altitude (340 km+) the radiation level is 4 times higher than here. The biggest problems the flers. That time the radiation level rise 10 or more times. It's still not lethal for a human, because it's only a few seconds long, but it could kills the sattelites.
[19:59] <prpplague> yea
[19:59] <prpplague> Hiena: just doing some research
[19:59] <Hiena> The earth's magnetic field is a great protection,
[19:59] <prpplague> Hiena: indeed
[20:00] <prpplague> Hiena: just curious what kind of techniques are using for computing environment on space craft like the space shuttle and on the ISS
[20:00] <Hiena> And that rise a problems for the interplanetary flights.
[20:00] <Hiena> Check the Motrola's rad hard series CPUs.
[20:02] <jcoxon> evening all
[20:02] <prpplague> Hiena: indeed, interplanetary stuff like is what i was interested in
[20:04] <Hiena> I guess the most popular is the Motorola 68k family. As i know, nowdays they producing it under the RadFire name.
[20:07] <prpplague> jcoxon: greetings
[20:07] <prpplague> Hiena: indeed, checking on the samsung arm9 stuff
[20:07] <prpplague> Hiena: looks like they have a rad-hard part number
[20:07] <prpplague> Hiena: just don't seem any on the open market
[20:07] <prpplague> Hiena: probably special order
[20:07] <Hiena> Well, if you left the earth's magnetic field, you have to create an artificial magnetic shield or have to build the ship from some shielding material like lead.
[20:08] <Hiena> I guess, these kind of "limited editions".
[20:08] <prpplague> Hiena: or based on what i've read, water is pretty darn good for protection
[20:08] <prpplague> Hiena: yea
[20:09] <prpplague> Hiena: yea i just checked the military grade chip is rad-hard and is special order
[20:09] <Hiena> Water? You means heavy-water?
[20:09] <prpplague> bigger package too
[20:09] <jcoxon> not many groups have the ability to do interplanetary flight :-D
[20:10] <prpplague> Hiena: no, just standard water
[20:10] <prpplague> jcoxon: indeed
[20:10] <prpplague> jcoxon: just an arm-chair design
[20:10] <jcoxon> :-) still a valid exercise who knows when it might come in useful
[20:11] <Hiena> Not many groups has an urge to do interplanetary flight. ;)
[20:11] <jcoxon> we'll get there in the end
[20:11] <jcoxon> hehe
[20:14] <Simon-MPFH> Evening folks
[20:15] <jcoxon> lots of new people here which is cool
[20:15] <prpplague> Simon-MPFH: greetings
[20:15] <jcoxon> (not that i think that the old timers aren't cool)
[20:15] Action: prpplague saw natrium42 's project on the web
[20:15] <Simon-MPFH> I'm wondering if anyone has a recommend for a radio system to gime me telnet (or ssh) to my onboard PC?
[20:15] <jcoxon> cool
[20:16] <Simon-MPFH> There seem to be lots in the states but I guess we have different regulations?
[20:16] <jcoxon> Simon-MPFH, in the UK?
[20:16] <jcoxon> what sort of range?
[20:16] <Simon-MPFH> Well, the more the better but I guess there are trade offs.
[20:17] <Simon-MPFH> 2 - 3Km would be a start
[20:17] <Simon-MPFH> http://www.radiometrix.co.uk/products/tdl2i.htm
[20:17] <jcoxon> on the ground of in the air?
[20:17] <jcoxon> of -> or?
[20:17] <Simon-MPFH> But some folks talk about getting 10s or even a couple of hundred K
[20:17] <Simon-MPFH> Air to Ground
[20:17] <Simon-MPFH> 2 way so I can 'talk' to the Gumstix(whatever)
[20:18] <jcoxon> hmmmmm, for range you'd want one of rocketboys radio modules
[20:18] <Simon-MPFH> Yes, UK
[20:18] <Simon-MPFH> You got a link?
[20:19] <jcoxon> they use radiometrix modules but they have some special modulating with a PIC
[20:19] <jcoxon> you'd have to ask him
[20:19] <jcoxon> when he is online
[20:19] <jcoxon> these are the modules we get the range with
[20:19] <Simon-MPFH> Ah - I see
[20:19] <jcoxon> http://wiki.ukhas.org.uk/communication:uplink
[20:20] <prpplague> just a note, i work for a company that makes a small sbc, i'm interested it in using it with these types of products
[20:20] <Simon-MPFH> Link?
[20:20] <prpplague> http://www.elinux.org/Hammer_Board http://www.tincantools.com
[20:21] <prpplague> just wanted to make sure that you didn't think i was trying to push our boards on the channel
[20:21] <jcoxon> :-)
[20:21] <Simon-MPFH> LOL, I'm not too stressed about that sort of thing as long as it's helpful
[20:21] <Simon-MPFH> What would you say the advantages are over a Gumstix?
[20:22] <jcoxon> yeah its no problem
[20:22] <Simon-MPFH> And of course, the obligitary Slashdot question
[20:22] <Simon-MPFH> "Does it run Linux?"
[20:23] <Simon-MPFH> All in the USA - You guys have waaaay more cool toys than we do
[20:24] <Simon-MPFH> Mind, the exchange rate helps to cover the postage costs!
[20:26] borism (n=boris@84-50-229-234-dsl.krw.estpak.ee) joined #highaltitude.
[20:27] <prpplague> Simon-MPFH: major advantage over the gumstix is the .1" pins, much easier to prototype with
[20:28] <prpplague> Simon-MPFH: everything is open on the hammer, including schematic
[20:28] <Simon-MPFH> Good points
[20:28] <jcoxon> looks nice
[20:28] <jcoxon> what sort of cost?
[20:28] <Simon-MPFH> Anyone selling them in the UK?
[20:28] <Simon-MPFH> $159
[20:28] <prpplague> $159USD for single unit
[20:29] <prpplague> Simon-MPFH: not as of yet, but we'll ship
[20:29] <prpplague> $249USD for the starter kti
[20:29] <prpplague> kit
[20:32] <Hiena> Okay. Have to set my vectors to the bed.
[20:32] <Hiena> Good night all!
[20:32] <Simon-MPFH> shutdown -h nwo
[20:32] Hiena (n=Hiena@81.93.195.181.datatrans.hu) left irc: "-=Alkoholmentes-sör és repülõgép-szimulátor, biztos út a guminõ felé=-"
[20:35] <prpplague> Simon-MPFH: the hammer is basically a large step up from stuff like avr's and pics
[20:37] <prpplague> Simon-MPFH: but not all the way up to the level of the gumstix where you need custom boards to interface to it
[20:40] <Simon-MPFH> Gotcha, I'm feeling the limits of the small AVRs now.
[20:40] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[20:41] <Simon-MPFH> I just wish My Nokia E90 had some GPIO lines - it has everything else a self respecting HA balloon man could want!
[20:42] <prpplague> hehe
[20:43] <prpplague> Simon-MPFH: yea, you can add on a nice cell phone module to the hammer pretty easy
[20:43] <Simon-MPFH> The telint one looks awesome
[20:50] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[20:51] <edmoore> evening everyone
[20:52] <edmoore> Simon-MPFH: Are you Simon Faulkner?
[20:52] <Simon-MPFH> Yes - just posted
[20:52] <edmoore> I spotted!
[20:52] <edmoore> Good idea with the E90
[20:53] <Simon-MPFH> He he - Would be an expensive loss if it went AWOL
[20:53] <edmoore> the only issue I can think of is that it's gsm, so will only work for about 0.5% of the flight, as it spends most of it's time above the altitude limit
[20:53] <Simon-MPFH> Indeed. Also it would freeze it's ass off up there
[20:53] <edmoore> A constant radio telemetry link is a real boon, and part of the fun of tracking it in real time
[20:54] <edmoore> normal consumer electronics seems to hold up amazingly well
[20:54] <Simon-MPFH> What radios to buy though?
[20:54] <edmoore> We've yet to have a problem
[20:54] <edmoore> well, we're limited round these parts by Ofcom's rather stringent 10mW limit
[20:54] <Simon-MPFH> Mmmm
[20:54] <edmoore> on a license free band, like 434MHz
[20:55] <edmoore> so we use 10mW 433/434 transmitters from radiometrix
[20:55] <edmoore> fnoble: are you about?
[20:55] <Simon-MPFH> This one? http://www.radiometrix.co.uk/products/tdl2i.htm
[20:56] <pattm> Simon-MPFH: The E90 can talk to an external bluetooth serial port
[20:56] <pattm> Simon-MPFH: and do external IO that way... i.e. a servo controller, etc
[20:56] <Simon-MPFH> Ah, of course - I have an ArduinoBT
[20:56] <pattm> sensors
[20:56] <pattm> whatever
[20:56] <prpplague> Simon-MPFH: you can use that module with something like the hammer pretty easy
[20:57] <edmoore> http://www.radiometrix.co.uk/products/ntx2nrx2.htm are the ones we use
[20:57] <prpplague> Simon-MPFH: i'd do away with the TTL level shifters to conserv power
[20:57] <edmoore> just the transmitter, and a decent radio scanner to receive
[20:57] <Simon-MPFH> OK
[20:57] <Simon-MPFH> What's decent?
[20:57] <Simon-MPFH> (I'm not the radio man!)
[20:57] Action: prpplague goes to meeting, bbiab
[20:57] <Simon-MPFH> I'm software and electronics
[20:58] <edmoore> me too, I sympathise
[20:58] <Simon-MPFH> I'm good on the sticks when it comes to manual control as well
[20:58] <Simon-MPFH> But radios is Mark (who has never been in IRC)
[20:59] <edmoore> Well if he has a scanner that'd be fine for testing
[20:59] <Simon-MPFH> I've got a 7100 something (somewhere in my junk box)
[20:59] <edmoore> and if you do it seriously then I'd suggest (unless you want to try and tackle the CAA) you do the first couple of flights with us in cambridge, and we have all the receiving kit
[21:00] <edmoore> - the kit being large directional yagi antennas and sensitive receivers
[21:01] <Simon-MPFH> Fair doos - I will bear that in mind
[21:01] <Simon-MPFH> CAA = Campaign Against Aviation?
[21:01] <edmoore> well you'd be forgiven for thinking it sometimes...
[21:01] <edmoore> but the civil aviation authority
[21:03] <edmoore> We have Steve (rocketboy on irc) who's a bit of a radio whizz and pretty much is responsible totally for what's now the standard way we do radio comms on balloons in the uk
[21:03] <Simon-MPFH> Ah, I shall ask him then...
[21:04] <Simon-MPFH> SWMBO is demanding attention - nice to meet you all - speak soon. SIm
[21:04] <Simon-MPFH> eject eject eject
[21:05] Simon-MPFH (n=simon@phantom.mpfh.co.uk) left irc: "Leaving"
[21:20] <prpplague> edmoore: what project are you working on?
[21:21] <edmoore> prpplague: The Nova/Martlet project
[21:21] <edmoore> cuspaceflight.co.uk
[21:21] Action: prpplague looks
[21:22] <edmoore> the site isn't that exciting atm iirc
[21:22] <prpplague> nice
[21:22] <edmoore> the stuff we've been working on for the last 6 months isn't on there yet
[21:22] <prpplague> edmoore: what are you using for your core electronics?
[21:23] <edmoore> currently an arm7 chip
[21:23] <edmoore> the nxp lpc2148
[21:23] <edmoore> and toying with an arm9 + fpga combo for the next flight computer
[21:24] <prpplague> edmoore: ahh
[21:24] <prpplague> edmoore: we make the hammer board http://www.elinux.org/Hammer_Board
[21:24] <edmoore> the arm7 is more than a match for all the ballooning stuff we do
[21:24] <prpplague> edmoore: indeed
[21:24] <edmoore> oh awesome
[21:24] <edmoore> I was looking at that
[21:25] <edmoore> a really impressive device!
[21:25] <edmoore> are you making a payload?
[21:25] <prpplague> thanks, too us about a year to develop and prototype
[21:25] <prpplague> took
[21:26] <edmoore> I can imagine! - how many layers is the pcb?
[21:26] <prpplague> 10 layers
[21:26] <edmoore> wow
[21:27] <edmoore> muct have been fun to route :)
[21:27] <prpplague> indeed
[21:28] <prpplague> edmoore: i see microsoft is a sponsor
[21:28] <edmoore> well that's a little convoluted
[21:28] <edmoore> prof Chris Bishop happens to be a rocket enthusiast and gave us some money
[21:28] <prpplague> hehe isn't it always?
[21:28] <edmoore> and runs the microsoft research lab at cambridge
[21:28] <prpplague> ahh
[21:29] <prpplague> edmoore: which arm9 were you considering using?
[21:29] <edmoore> lpc3180 as it has a floating point unit, but I don't hear great things about the silicon
[21:29] <edmoore> the other option was to use one of the telit gsm modules which have a built in arm9 entirely for customer use
[21:30] <prpplague> ahh interesting
[21:30] <edmoore> I don't know which arm9 though, not got as far as that, just saw it and thought it looked interesting
[21:30] <prpplague> edmoore: is that due to cost factors?
[21:31] <edmoore> well, it's convenient in that it's less construction work for us
[21:31] <edmoore> they're not all that cheap
[21:31] <edmoore> and the fpga would do all the interfacing and servo driving and other boring bits
[21:32] <edmoore> the floating point unit would be useful for the inertial navigation atuff
[21:32] <edmoore> stuff*
[21:32] <edmoore> but this is me talking about sutff I don't really know about as a lowly undergrad
[21:32] <prpplague> edmoore: with softfloat under linux you get pretty good performance with an arm9
[21:33] <prpplague> edmoore: well if you are interested in using the hammer, i'm sure we could come up with a couple eval kits and 200 quid, hehe
[21:33] <edmoore> indeed, though we'd be really pushing it. The kalman filter seems to expand to fit the space available, and I'd quite like to give it as much space as possible!
[21:33] <edmoore> oooooh
[21:33] <edmoore> that's actually really very tempting!
[21:33] <edmoore> fnoble is the other electronics guy
[21:34] <edmoore> he doesn't seem to be actually about atm
[21:34] <prpplague> edmoore: np, i'm just about always around during the day
[21:35] <edmoore> I'd not considered using linux but that's only because I come to embedded micros from the bottoms (avrs and PICs) up rather than down from PCs, so I only really know dedicated C and simple rtos's
[21:35] <edmoore> but this might be a great way to actually learn linux from a useful bottom-up approach, which i'd love to do
[21:35] <prpplague> edmoore: ahh, well there are some good RTOS patches
[21:36] <prpplague> edmoore: for linux that is
[21:36] <prpplague> edmoore: which fpga were you guys considering?
[21:37] <edmoore> well.....
[21:37] <edmoore> fnoble has just bought a dev board which he thinks was an altera something, but can't remember. I have a spartan 3e dev board
[21:38] <prpplague> ahh
[21:38] <edmoore> I've not really used it properly, and have never done any fpga stuff before, so essentailly it's a totaslly unmade decision
[21:38] <prpplague> the s3e is a good one to work with
[21:38] <edmoore> do you have any advice>
[21:38] <edmoore> ?*
[21:38] <edmoore> cool, I've heard that. My director of studies is an EE and talks highly of them
[21:39] <prpplague> edmoore: s3e is pretty darn good, it all depends on what items you need to do
[21:39] <edmoore> my idea would be to memory map the fpga to the external mem bus of the arm
[21:40] <prpplague> edmoore: you might find running the s3c2410 with some smaller avr's like the atmega48's might work better than a fpga, thats just my opinion
[21:40] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc: Read error: 104 (Connection reset by peer)
[21:40] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[21:40] <prpplague> edmoore: re
[21:40] <edmoore> sorry, pulled ethernet cable out. So yeah, the fpga would take up maybe the last few bytes of address space, and it would do the spi interfacing to the sensors, it would generate pwm for servos
[21:40] <edmoore> and various other interfacey type things
[21:41] <edmoore> re?
[21:41] <prpplague> edmoore: irc slang for welcome back
[21:41] <edmoore> ignorance is cured one step at a time :)
[21:41] <prpplague> hehe, indeed
[21:41] <edmoore> so the arm would just write a servo pos to memory, which would actually be to the fpga
[21:42] <prpplague> gotcha
[21:42] <edmoore> do you think that's a sensible way to go about it?
[21:42] <edmoore> would it be better to maybe have an spi interface between the fpga and the arm?
[21:42] <prpplague> indeed many of the robotics devrs do that
[21:43] <prpplague> edmoore: other's use small avr's like the atmega48 via spi to control specific options
[21:43] <edmoore> it would make coding for the arm a lot nicer
[21:43] <edmoore> yeah, that's the other option
[21:43] <edmoore> the thing is that the flight computwe
[21:43] <edmoore> whoops
[21:44] <edmoore> the flight computer would be a card with conceivably anything grafted onto it, so I like the flexibility of the fpga
[21:44] <prpplague> edmoore: code wise under linux, the spi ports are memory mapped, so sending data to them is pretty easy
[21:44] <edmoore> oh that's good
[21:44] <prpplague> edmoore: indeed
[21:45] <prpplague> edmoore: yea, i'm kinda doing a little research to see what kind of requirements people have for such flight computer controls
[21:45] <edmoore> Yeah. With the arm7 board, it takes a seperate chip to run the inertial measurement unit and do all the sensor fusion and quaternion calcs and so forth
[21:46] <edmoore> with the arm9/fpga, I'd envisaged all that sort of dsp stuff being done on the flight computer
[21:46] <edmoore> as the other stuff takes no time (parsing gps data, writing to the flight log, landing spot prediction or whatever)
[21:47] <prpplague> edmoore: ahh
[21:47] <prpplague> edmoore: shouldn't be too hard to generate a fpga board with an arm combo
[21:48] <prpplague> edmoore: you could do a 8-bit databus with the fpga using the hammer pretty easy
[21:48] <prpplague> edmoore: we've been considering doing a combo fpga board with the s3e for some time
[21:48] <edmoore> awesome. It does seem pretty exciting.
[21:49] <edmoore> I've not looked at it, but I guess configuring the fpga on startup must be fairly straightforward?
[21:50] <prpplague> edmoore: yea, you can read directly from a storage device, upload via a jtag, or upload via a uart style interface
[21:50] <prpplague> edmoore: that could be done from the arm board pretty easily
[21:50] <edmoore> cool. This is starting to sound all rather promising
[21:55] <prpplague> edmoore: drop me an email if you have any questions about the hammer: dave123_aml@yahoo.com
[21:55] <edmoore> yes I will certainly do that. I'll talk to fnoble to see what he thinks
[21:56] <prpplague> ok great!
[21:56] <edmoore> we've still got a fair bit of milage to get out of our arm7 computer yet
[21:56] <edmoore> trying a few light rtos's
[21:56] <edmoore> maybe try writing one just to say I can!
[21:57] <prpplague> indeed, probably be a few months before we get a s3e fpga board ready
[21:58] <edmoore> cool, well i'm going to hit the gym then get an early night. Great talking to you!
[21:58] <prpplague> edmoore: okie dokie, later!
[21:58] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc:
[21:58] <prpplague> edmoore: good talking to you as well
[22:09] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[22:11] <edmoore> gym closed...
[22:12] <prpplague> doh
[22:12] <prpplague> s/gym/pub
[22:12] <edmoore> s?
[22:12] <prpplague> subsitute
[22:12] <prpplague> go to the pub instead
[22:12] <edmoore> ah. speaking in vi or something :p
[22:13] <prpplague> yea unix slang
[22:13] <edmoore> again, one step at a time
[22:13] <edmoore> it's been a bit of a learning curve, this electronics/unixy stuff
[22:13] <prpplague> hehe, np, i've been tinkering for a long time
[22:14] <edmoore> I'm looking forward to one day knowing roughly what I'm doing
[22:15] <prpplague> edmoore: well, i am not sure if it is a statement about me or the field of embedded development, but i've been saying the same thing for about 20 years
[22:15] <edmoore> :)
[22:57] borism (n=boris@84-50-229-234-dsl.krw.estpak.ee) left irc: Read error: 145 (Connection timed out)
[23:05] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[23:06] edmoore_ (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[23:06] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc: Read error: 104 (Connection reset by peer)
[23:15] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[23:20] edmoore_ (n=edmoore@pomegranate.chu.cam.ac.uk) left irc:
[23:25] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[23:31] prpplague (n=dave@mail.americanmicrosystems.com) left irc: "Leaving"
[23:43] kc0wys_ (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[23:53] jcoxon (n=jcoxon@host86-129-62-157.range86-129.btcentralplus.com) left irc: "Leaving"
[23:54] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) left irc: Read error: 110 (Connection timed out)
[23:55] kc0wys (n=kc0wys@71-14-177-245.dhcp.stls.mo.charter.com) joined #highaltitude.
[00:00] --- Tue Jan 29 2008