#robotics Logs

Jun 08 2012

00:01 MarkCSylvan with butter
00:02 MarkCSylvan ascdasd
00:03 MarkCSylvan hat strange i couldnt send to the electronics channel;
00:04 furrywolf I don't want animated anything.
00:04 furrywolf grr, wrong window
00:05 furrywolf that's because you don't have a registered nick, so LoRez doesn't like you. if you register your nick and identify to it, or talk sense into LoRez, then you'll be able to send to the electronics channel.
00:05 katsmeow-afk but why would you be int hat channel anyhow? too much drama
00:06 furrywolf it doesn't have drama problems, it has idiot problems, and no ops to deal with them. theBear is the only useful op, and he has a lot of non-irc stuff to take care of.
00:06 furrywolf most ops are never around or never perform channel management
00:09 theBear tho i am back... as most changes in life i dunno how often i'll be here, but so far, it's a lot
00:22 tsmeow-afk didn't know furry was an actual les
00:23 rrywolf is soft and fl
00:23 home there are girls on here?
00:23 home what the?
00:23 katsmeow-afk duh
00:24 home but..but! There are no girls on the internet's :o
00:25 rue_mohr furrywolf, as long as flyback is still in there, dont evn bother with #electronics
00:29 MarkCSylvan rue you still in sask ?
00:31 rue_bed never was
00:31 rue_bed I knew someone out there once tho
00:31 rue_bed an electronics hobbyist
00:32 rue_bed first name started with a D I think
00:32 katsmeow-afk holycrap, someone spelled "hobbyist" on irc correctly!!!!!
00:32 rue_bed ?
00:32 eBear is totally out t
00:32 theBear and it was RUE !!!!!
00:33 theBear unprecendented :)
00:33 katsmeow-afk for real!!!
00:33 katsmeow-afk and unprecedented!
00:33 rue_bed :/ your saying I cant speel properly?
00:33 MarkCSylvan ?
00:33 theBear no rue, we'd never say anything like that
00:33 MarkCSylvan where are you at then ?
00:34 katsmeow-afk not quite like that, no
00:34 rue_bed sunshine coast
00:34 rue_bed not the one in australlia
00:34 rue_bed the other one
00:34 MarkCSylvan bc ?
00:34 rue_bed yes
00:35 MarkCSylvan i use to come on here under the handle n1x0n
00:35 rue_bed !seen n1x0n
00:35 tobbor n1x0n was last seen in #robotics on Aug 06 23:26 2009
00:35 rue_bed ok
00:36 rue_bed !thislog
00:36 tobbor This one: http://rueshouse.dyndns.org:82/~ircjunk/irclogs/html/%23robotics-2012-06-08.html
00:36 rue_bed http://rueshouse.dyndns.org:82/~ircjunk/irclogs/html/%23robotics-2009-08-06.html
00:37 rue_bed n1x0n:rue_mohr: i am comming your way got a bed ready :P
00:37 MarkCSylvan lol
00:37 MarkCSylvan yep that was me
00:37 MarkCSylvan P
00:37 furrywolf katsmeow-afk: I'm beginning to think that channel is filled with dicks (metaphorically, not literally).
00:38 rue_bed it took 3 years?
00:38 rue_bed did yo crawl?
00:38 MarkCSylvan i been spending lots of time in BC mostly in west van and the koteneys
00:38 rue_bed or did yo walk back and forth a few times?
00:38 rue_bed ah
00:38 MarkCSylvan nah had a couple kids
00:38 MarkCSylvan openned up a big store
00:38 rue_bed oooh
00:38 rue_bed that'd do it
00:39 MarkCSylvan made a bunch of money
00:39 rue_bed come out with any of it?
00:39 katsmeow-afk furry, i just left it
00:39 MarkCSylvan there are a couple hacker spaces out here now and they have irc channels
00:39 home electronics?
00:39 rue_bed ah
00:39 MarkCSylvan i actully found gold last time i was in BC
00:39 rue_bed got you thinking eh?
00:39 MarkCSylvan on the arrow lakes
00:39 MarkCSylvan :P
00:39 MarkCSylvan i dont even have a real irc client right ni
00:40 MarkCSylvan now
00:40 home MarkCSylvan: BC as in briish collumubia?
00:40 rue_bed well I'm pretty sure you could hit me with a short range missle from vancouver
00:40 MarkCSylvan yes
00:40 rue_bed zhanx, whats the range of a short range missle?
00:41 rue_bed if your allowed to tell us
00:41 MarkCSylvan last time i was there i was in the fairmont waterfront
00:41 rue_bed well I dont remmeber anything about ya
00:41 MarkCSylvan nice place
00:52 furrywolf bbl
04:12 iR0b0t1 I am trying to receive a pulse between 20 and 40�s (I send a 30�s pulse). I am using a pin change interrupt - the first call passes through, the second call checks if the timer has elapsed anywhere between 20 * ticks_per_us and 40 * ticks_per_us counts.
04:12 iR0b0t1 However I don't receive every pulse.
04:12 iR0b0t1 Is 30�s pushing it for a tiny85?
04:31 Triffid_Hunter iR0b0t1: yep, you'd best look at the input capture timer stuff for that
04:34 theBear i remember long long ago doing something timing related where i had something silly like 8 cycles between 2 things happening, i ended up looking at the generated asm (too lazy to do my own asm functions in C, plus i don't know how :) and count cycles vs clock speed to be sure i'd make it
05:04 iR0b0t1 Triffid_Hunter: theBear: What was happening was I enabled the timer 1 overflow interrupt and forgot to define an interrupt vector.
05:04 iR0b0t1 So the MCU would reset and miss a signal.
05:04 iR0b0t1 I figured this out when it missed less pulses when clocked more slowly.
05:05 0b0t1
05:24 theBear hehe, we all done sillier things than that in the past :)
05:29 Triffid_Hunter iR0b0t1: still, it does take a few uS to even get to your interrupt code so if that's the only interrupt happening you might be ok but if there's other stuff going on too you need an input capture using a timer so it doesn't matter if your interrupt is late
06:15 Silent :)
06:16 Silent Hello. I would like to get into robotics and microcontroller programming. What's my first step?
06:16 Triffid_Hunter Silent: get an arduino :)
06:17 Silent Ah, just the kind of answer I was looking for :)
06:17 Silent Arduino Uno?
06:18 Triffid_Hunter Silent: get whichever is easiest for you to get. at some point you may want another of a different sort, but you can't predict what's going to best suit your learning style
06:18 Triffid_Hunter Silent: and there's basically two types anyway, the small '328-based ones (diecimila, duemilanove, uno, etc) and the mega series which are more expensive but have significantly more I/O pins
06:19 Silent There is no 'easiest to get', I'm probably going to have to ship it form the US or go to another city to buy it from a distributor.
06:19 Triffid_Hunter Silent: can get packs on ebay with arduino, lcd screen, buttons, maybe a breadboard or some other doodad
06:19 Silent I'm trying to make up my mind about what board I should get right now
06:19 Triffid_Hunter Silent: also go browse pololu and sparkfun shops
06:20 iR0b0t1 The Mega series is ridiculously overpriced FYI. They mark it up 100% even though it costs almost the same to produce.
06:20 Silent Alright
06:20 Triffid_Hunter Silent: uno or similar clone will be a great starter
06:20 Silent Also, about the uno - can I de-attach the chip after I finish programming?
06:20 Triffid_Hunter iR0b0t1: I don't get italian ones, I get them from hong kong.. the quality is way better!
06:21 Triffid_Hunter Silent: on all the ones I've seen you can, but I suspect they may be branching into surface mount chips these days
06:21 iR0b0t1 hah
06:21 Triffid_Hunter Silent: if you want to pull the chip and put it in your project, remember the 16MHz crystal :)
06:21 Silent But will I have to de-solder it?
06:21 Silent Isn't there a base of some sort, like you have on some mobos for the BIOS chip?
06:21 Triffid_Hunter Silent: naw they're socketed
06:22 Silent Basically what I'm asking is if I will need the whole board or just the chip to build something and make it work
06:22 Silent It would be nice if I could test stuff with the board and then take the chip out to solder stuff directly to it's pins
06:23 Triffid_Hunter Silent: yeah that's the idea and you can do just that
06:23 Triffid_Hunter Silent: as long as you remember the 16MHz crystal
06:23 Silent What's that?
06:23 Triffid_Hunter Silent: the chip does have an internal oscillator but it's usually disabled in favour of an external crystal
06:23 iR0b0t1 If you buy two arduinos, you should be able to use one as an ISP as reset the fuses
06:23 iR0b0t1 Or you could if they have that added yet. I know low-voltage programming can set fuses.
06:24 Triffid_Hunter Silent: the crystal controls how fast it runs. the chips are rated to 20MHz but most of the arduino code is hard-coded for 16MHz
06:24 Silent I see
06:24 Silent And if I take it out?
06:25 Triffid_Hunter Silent: if it's programmed to use a crystal and it has no crystal, it won't run until you give it its crystal
06:25 Silent I see.
06:26 Silent And if I program it to use no crystal, but there is a crystal anyway?
06:26 Triffid_Hunter Silent: then it'll ignore the crystal, but all your timings will be different if you use arduino libraries
06:26 Triffid_Hunter Silent: because the internal oscillator only runs at 4MHz or something like that
06:27 Silent I should really read something about it before I order stuff.
06:27 Silent Could you suggest a nice book and an emulator?
06:28 Triffid_Hunter Silent: heh don't know of either.. arduino website has tons of info geared towards newbies, I'm sure you'll find stuff about using the internal oscillator in the forums therte
06:28 Triffid_Hunter Silent: may also want to hop over to atmel.com and find the atmega328P datasheet
06:29 Triffid_Hunter the full one, not the technical brief or anything like that, should be around 600 pages
06:29 Silent Jesus.
06:30 Silent Arduino is using C, right?
06:30 Triffid_Hunter Silent: don't worry, it's all neatly laid out in chapters and sections, and I'm not suggesting you read the whole thing
06:31 Triffid_Hunter Silent: arduino uses a small subset of C++
06:31 Triffid_Hunter Silent: but you can program your hardware in straight C if you prefer and dodge the arduino libraries
06:31 Triffid_Hunter Silent: see http://github.com/triffid/Teacup_Firmware for an example of that
06:31 Silent I like C over C++
06:32 Triffid_Hunter Silent: programming microcontrollers is a whole new experience from programming larger systems, eg you really want to avoid malloc() at all costs
06:32 Silent Really?
06:33 Triffid_Hunter Silent: yeah, think of it like this: you get 1k of ram on your chip. you need to set aside maybe 256 bytes for stack, and some for static variables. what's left can be heap or more stack. how much memory do you want to use purely to keep track of what's used and what's free?
06:34 Triffid_Hunter Silent: oh sorry the '328 has 2k of ram, but same principle applies
06:35 Silent I see
06:35 Triffid_Hunter Silent: also, doing continuous malloc/free will fragment your memory map, how many cycles do you want to use looking for a large enough free section in the memory?
06:36 Silent I never thought of that.
06:36 Triffid_Hunter Silent: note that each assembly instruction takes 1, 2 or 3 clock cycles depending on the instruction. the core is 8 bits, so a 32 bit add will take (at a guess) 10-14 instructions. so now we're looking at a couple of microseconds for a 32-bit add, how long do you want to spend just managing memory?
06:37 Triffid_Hunter may not sound like much until you realise that a floating point operation is hundreds of microseconds, and a servo pulse is 1 to 2 milliseconds wide
06:38 Triffid_Hunter so you start seeing that individual building blocks that you throw around like confetti on desktop machines take significant percentages of your signal times on microcontrollers
06:38 Triffid_Hunter Silent: don't get me wrong, it's an amazingly fun journey, but you must understand that it may as well be a new language to learn that simply looks familiar to what you know now ;)
06:38 Silent Sounds like a hard thing to get used to
06:38 Triffid_Hunter Silent: not at all, just a different approach
06:38 Silent Haha that's the whole point, isn't it?
06:39 Triffid_Hunter :)
06:39 Silent Well I'm glad you gave me a brief intro
06:39 Silent Thanks
06:39 Triffid_Hunter Silent: reprap firmwares are great examples of what can be made to fit on these chips
06:39 Silent I found some tuts on the Arduino site
06:40 Triffid_Hunter can even do simple web servers and things as long as you're prepared for them to curl up and die if you try to hit them too hard
06:40 Silent Define hit?
06:42 Triffid_Hunter Silent: most modern web browsers will happily make 20-30 concurrent connections to a single server and request stuff in parallel across them. just try that with an arduino with ethernet shield and see how you go ;)
06:42 Triffid_Hunter Silent: consider: a typical ethernet packet is 1500 bytes. the chip has 2048 bytes of ram...
06:42 Silent Ah
06:42 Silent Sounds painful lol
06:43 Triffid_Hunter yeah, if you want to serve heaps of data without the thing falling over, get a raspberry pi or beaglebone or something, even an lpcxpresso or f4 discovery will handle that sort of stuff better if you hook ethernet up
06:44 Silent Thanks for the info
06:44 Silent Well actually I wanna get one to fool around and try to build some robots
06:45 Silent Gonna try and invent something new perhaps ;)
06:45 Triffid_Hunter Silent: yeah cool, grab a dual output motor shield from pololu or sparkfun then
06:45 Triffid_Hunter maybe some sharp GP2D120s and a sonar and some hobby servos
06:46 Triffid_Hunter Silent: the other thing to remembe with programming microcontrollers is that the chip has tons of awesome hardware in it to do stuff for you, use it as much as you possibly can
06:47 Triffid_Hunter Silent: eg check out the input capture feature of the timers for your sonar, and the PWM output feature for driving the motors
06:47 Silent Alright
06:47 Silent Well it was amazing talking to you
06:48 Triffid_Hunter Silent: so instead of generating all the signals with your code, you just write some hardware registers, the chip does all the heavy lifting for you, and your code just writes some numbers every so often
06:48 Silent You managed it to wake up the little dark evil inventor parts of my mind
06:48 Triffid_Hunter Silent: have fun :)
06:48 Silent Thanks :D
06:48 Triffid_Hunter Silent: excellent :D
06:48 Triffid_Hunter Silent: prediction: two months from now, you'll be buying a reprap :
06:48 Triffid_Hunter :P
06:48 Silent Well I must setup Slax now
06:49 Silent I'll write that down and we'll see how correct you were.
06:49 Silent Either way, bye and thanks again :)
06:59 cambazz hello people!
08:52 rue_mohr "one of the cats is sucha good mouser she dosnt even have to .... leave.... the ..... house to catch them....?"
08:56 rue_mohr http://www.ebay.com/itm/Tektronix-2215-Oscilloscope-2-Channel-60MHz-/140501405355 <-- must have been shipped by UPS
09:11 rue_mohr http://www.princessauto.com/pal/product/8190415/Manual/Pneumatic-5-Way%2C-3-Position-Lever-Control-Valve
09:11 rue_mohr hmm
13:30 furrywolf "Recent updates to your order" "Your item(s) has been marked as shipped." "Item Name: Adult Strapless Dildo" "Item Name: Adult Strapless Dildo Blue" yay! now to hope they're not fakes like the last two I got on ebay. :(
15:03 furrywolf I just offered someone on craigslist $250 for 550W of panels. I predict no, but never hurts to try...
15:11 furrywolf it'd be a nice upgrade to my system, but I don't have enough money to offer more than that.
15:32 furrywolf looks like he'll take $300.
15:32 furrywolf that's not too bad of a $/watt price...
15:35 furrywolf they're Arcos, so I'll need to see what they look like before parting with any cash.
18:46 rue_mohr our 260W are about $450
22:36 furrywolf well, I now own more solar stuff.
22:37 furrywolf got 8 yellowed arco 55W panels and 2 good siemens 55W panels for $250 (550W total, $0.45/watt), plus a tri-metric battery meter, 500A current shunt, a marine dual battery switch, and a bucketload of 2/0 cables, for another $50.
22:38 furrywolf I'm now broke, but I have shiny things.
22:55 furrywolf http://www.altestore.com/store/Meters-Communications-Site-Analysis/Meters-Battery-Monitors/Ammeters-Voltmeters-Battery-Monitors/Bogart-Engineering-TM-2020-TriMetric-Meter-Battery-Monitor/p254/
22:55 furrywolf now have one of those
23:09 furrywolf meh, only works with low-side shunts... all mine are wired high-side.
23:11 furrywolf I guess I'll wire the shunt it came with in the negative, but that means major re-wiring, as my grounds are spread out.
23:14 rue_mohr i can show you a current mirror
23:16 rue_mohr it shifts the level of the sense voltage to whatever rail you want
23:16 rue_mohr I was gonna use it on buddy, but I have twice as many power rails as ground rails
23:22 rue_mohr !assist circuits
23:22 tobbor Possibly http://eds.dyndns.org/~ircjunk/circuits
23:27 rue_mohr hmm
23:29 furrywolf lol @ zappy
23:30 furrywolf I've never used public transit in SF, so can't help much there.
23:30 furrywolf grr, wrong window
23:34 rue_mohr I cant find it
23:43 katsmeow .
23:44 furrywolf .*tickle*
23:44 katsmeow ack!
23:47 katsmeow i feel like every time i cannot go outside because of garbage smoke, it's as if the world is yelling at me that i cannot stay among humans, they seem to love the nose-burning eye-watering stench of burning garbage
23:50 katsmeow i look at the huge pile of insulation on the scaffolding, and know there is no point in installing it
23:51 katsmeow it's therefore 100% wasted money too
23:52 furrywolf heh
23:52 katsmeow what?
23:53 rrywolf is too exhausted to think of a better resp
23:53 rue_mohr sell it to a sketchy contractor
23:54 katsmeow sketchy? it's new insulaton, in rolls, never opened
23:54 katsmeow R19 and R25
23:56 rue_mohr only a sketchy one would buy it from a non-construction store
23:56 katsmeow o
23:56 rue_mohr furthermore, nobody up there would use insulation that thick, so a sketchy constructor would tear it in half
23:57 tsmeow points out being able to heat her 16x16 bedroom with two kerosene lamps or 1 propane camp lamp when it's 25F outside for 3 daysand n
23:58 rue_mohr yes
23:59 rue_mohr which you know is much more advanced than they can comprehend
23:59 katsmeow yeas, but i thought they could up there
23:59 rue_mohr up where?
23:59 rue_mohr canada?
23:59 katsmeow but not even you insulates their house over R3
23:59 katsmeow yeas