2010-08-28 00:01 <DocScrutinizer> either you 'tune' the circuit, means in-Z == trace-Z == out-Z. Or you feed 'asym' with very low source-Z and proper termination, so the missmatch has no adverse side effects
2010-08-28 00:02 <DocScrutinizer> wpwrak: sorry, I'm not cmpetent to answer specific detail questions wrt that
2010-08-28 00:04 <wpwrak> hmm, on rx, the differential impedance of the transceiver is 100 Ohm.
2010-08-28 00:04 <wpwrak> nothing specific to find about TX.
2010-08-28 00:04 <DocScrutinizer> there's programs to calculate such things, and in appnotes the chip manufs clearly signal which parts need to be tuned. This is based on their knowledge about chip fan-out/fan-in or Z properties, and on simply analyzing lab proto boards
2010-08-28 00:05 <wpwrak> the docs are a bit fuzzy. and contradict each other :)
2010-08-28 00:07 <DocScrutinizer> as a general rule of thumb, you don't care about tuned lines, when the loss caused by mismatch is irrelevant. Then you just make sure you don't run into other truble by line ringing (reflections or standing waves)
2010-08-28 00:07 <wpwrak> e.g., ti don't specify anything. they give a balun using transmission lines for inductors in their reference design. if you dig further, they do mention an integrated balun in one web forum. and one rf component maker even has a balun supposedly designed for that chip.
2010-08-28 00:08 <wpwrak> (information is similarly confusing with atmel, although with less secrecy)
2010-08-28 00:08 <DocScrutinizer> :nod:
2010-08-28 00:09 <wpwrak> okay. what would be typical mistakes to avoid when ringing may be an issue ?
2010-08-28 00:09 <DocScrutinizer> RF design is black magic - you're supposed to have learnt that lesson :-P
2010-08-28 00:09 <wpwrak> yeah yeah :)
2010-08-28 00:09 <wpwrak> i don't aim at cooking up a perfect fcc- and etsi-pleasing design that's ready for MP :)
2010-08-28 00:10 <DocScrutinizer> wpwrak: typical mistakes: too long traces, too high terimation Z, to high source Z
2010-08-28 00:10 <DocScrutinizer> termination*
2010-08-28 00:10 <wpwrak> i'll be happy already if i emit more power around the carrier than at the harmonics and get a bit of range :)
2010-08-28 00:10 <DocScrutinizer> missing clamp diodes (if digital signal)
2010-08-28 00:11 <wpwrak> (z) one end is given by the antenna, 50 R. the other is defined by the balun. feed line is ~10 mm in total.
2010-08-28 00:11 <wpwrak> this is the pcb: http://www.almesberger.net/misc/ben/wpan/first-pcb.jpg
2010-08-28 00:12 <DocScrutinizer> hmm, so good PCB layout progs have a function to make a trace match 50R Z
2010-08-28 00:12 <wpwrak> and here with components: http://www.almesberger.net/misc/ben/wpan/board-100813.jpg
2010-08-28 00:12 <wpwrak> kicad doesn't have impedance matched trace. i know they should be about 1.6 mm wide, though.
2010-08-28 00:13 <wpwrak> here's some of my research for now: http://projects.qi-hardware.com/index.php/p/ben-wpan/source/tree/master/atrf/ecn/ecn0004.txt
2010-08-28 00:13 <DocScrutinizer> so design it that way. If you want to do a fancy, design 5..10 PCBA with a range of trace geometry, and check which performs best
2010-08-28 00:14 <wpwrak> yeha, "try a few things and see what works best" does indeed look like the way to go
2010-08-28 00:15 <DocScrutinizer> (in the end of the day that's what industry at large does as well)
2010-08-28 00:15 <wpwrak> luckily, i can replace some of the small chips with an integrated balun, so there will be fewer knobs to turn. should also generally perform better.
2010-08-28 00:15 <DocScrutinizer> if peak performance is at either end of your range, you should go for another set
2010-08-28 00:17 <DocScrutinizer> also, as a catch-oops, usually you see unpopulated Pi-filters at start and end of tuned traces
2010-08-28 00:17 <wpwrak> yup. right now, i have suckish reach. barely makes it room to room. interestingly, one direction works much better than the other. (the two boards have some small component variations, that's probably why)
2010-08-28 00:18 <wpwrak> (pi) that may be for fcc compliance
2010-08-28 00:18 <DocScrutinizer> if after start of first batch of 10k PCB it turns out the mismatch is too severe, you always can throw a bead and 2 C at it
2010-08-28 00:19 <wpwrak> i saw this approach in many app notes. first they design and simulate the perfect circuit. then they build it and throw in filters until the unwanted harmonics and stuff are small enough to pass certification.
2010-08-28 00:19 <DocScrutinizer> yep. usual SOP
2010-08-28 00:20 <wpwrak> well, my board is so small that the unpopulated pi filter would already cover most of the feed line :)
2010-08-28 00:20 <DocScrutinizer> the Pi are for SWR / Z matching though
2010-08-28 00:20 <wpwrak> there is actually one at the end
2010-08-28 00:21 <DocScrutinizer> you see these (usually) unpopulated Pi at every RF design antenna foot point
2010-08-28 00:22 <DocScrutinizer> in case antenna impedance changes later on, to what it was during proto tests
2010-08-28 00:22 <DocScrutinizer> really *every*
2010-08-28 00:23 <DocScrutinizer> each BT or WLAN module, each GSM design
2010-08-28 00:23 <wpwrak> so they place a 0R ? or use a transmission line as inductor ?
2010-08-28 00:23 <DocScrutinizer> 0R
2010-08-28 00:25 <DocScrutinizer> and the 2 C are NC
2010-08-28 00:25 <wpwrak> i've seen one antenna design recommend a LC termination ("half-T")
2010-08-28 00:25 <DocScrutinizer> hmm, you do this if you know in advance your antenna is detuned
2010-08-28 00:26 <wpwrak> they do show remarkably better performance with the LC in place ;)
2010-08-28 00:26 <DocScrutinizer> sometimes you simply cant get a lambda/4 or whatever
2010-08-28 00:27 <wpwrak> ah, and how close can/should the antenna be to the transceiver ? is there a minimum clearance one would normally try to observe ?
2010-08-28 00:27 <DocScrutinizer> not to my knowledge
2010-08-28 00:28 <DocScrutinizer> usually the closer the better
2010-08-28 00:28 <wpwrak> kewl
2010-08-28 00:28 <DocScrutinizer> footpoint that is
2010-08-28 00:28 <DocScrutinizer> :-)
2010-08-28 00:28 <DocScrutinizer> antenna tip should be max free air around in all directions
2010-08-28 00:29 <wpwrak> should short feed lines be bracketed by GND ? or is the ground plane underneath sufficient ?
2010-08-28 00:29 <DocScrutinizer> should suffice
2010-08-28 00:29 <wpwrak> hmm, the definition of "antenna tip" may be a bit tricky in my case :)
2010-08-28 00:30 <DocScrutinizer> yeah, sontimes it is :-D
2010-08-28 00:30 <DocScrutinizer> ~ping
2010-08-28 00:30 <DocScrutinizer> mhm
2010-08-28 00:31 <wpwrak> ti's design [1] feeds the antenna from the long side and has free space on the left. [1] http://focus.ti.com/lit/an/swra117d/swra117d.pdf
2010-08-28 00:32 <wpwrak> i have the left side blocked with the circuit and the feed line goes around. not sure how horrible this is in the general scale of things.
2010-08-28 00:32 <wpwrak> of course, nobody has a useful antenna design that's fed from the short side :-(
2010-08-28 00:35 <wpwrak> pinged the wrong bot ? :)
2010-08-28 00:36 <DocScrutinizer> what's wrong with mgedmin's logbot? the log is laggy like hell
2010-08-28 00:37 <DocScrutinizer> (wrong bot) nah, 24h forced disconn
2010-08-28 00:38 <DocScrutinizer> qi-bot: ?
2010-08-28 00:39 <DocScrutinizer> qi-bot: info
2010-08-28 00:39 <wpwrak> i think qi-bot is only logging, nothing else
2010-08-28 00:39 <DocScrutinizer> qi-bot?
2010-08-28 00:39 <DocScrutinizer> logging?
2010-08-28 00:40 <DocScrutinizer> don't think so, or maybe... >Generated by irclog2html.py 2.7 by Marius Gedminas - find it at mg.pov.lt!<
2010-08-28 00:42 <DocScrutinizer> eggdrop doesn't look like povbot
2010-08-28 00:42 <DocScrutinizer> well, maybe I'm wrong
2010-08-28 00:43 <DocScrutinizer> probably irclog(c)eggdrop, http://en.qi-hardware.com/irclogs(c)mgedmin
2010-08-28 00:46 <wolfspraul> DocScrutinizer: qi-bot is only logging, the entire setup, every last configuration option, is documented here http://en.qi-hardware.com/wiki/Server_setup#eggdrop
2010-08-28 00:46 <DocScrutinizer> compare http://mg.pov.lt/maemo-irclog, it's povpot there that does the logging
2010-08-28 00:46 <DocScrutinizer> wolfspraul: :-D, yep thought as much
2010-08-28 00:47 <wolfspraul> then irclog2html picks it up, it's equally documented http://en.qi-hardware.com/wiki/Server_setup#irclog2html
2010-08-28 00:47 <DocScrutinizer> now for the 3 lines of wpwrak I missed during downtime
2010-08-28 00:47 <wolfspraul> cron job every 30 minutes, finally the result comes out at http://en.qi-hardware.com/irclogs
2010-08-28 00:47 <wolfspraul> it's a bit delayed, first eggdrop only flushes the log file every few minutes I think, and then mostly the cron job only runs every 30 minutes
2010-08-28 00:47 <DocScrutinizer> aaah, so the cronjob is introducing the enormous lag
2010-08-28 00:47 <wpwrak> oh, i could have repeated them :)
2010-08-28 00:48 <DocScrutinizer> I didn't know there were any, wpwrak :-)
2010-08-28 00:48 <wolfspraul> I can change the cron to run faster
2010-08-28 00:48 <wolfspraul> the next thing I plan to add to qi-bot is an opt-out list of nicknames, so the bot will automatically discard all msgs from people who don't want to be logged
2010-08-28 00:49 <DocScrutinizer> yay
2010-08-28 00:49 <wolfspraul> but it's not the #1 on my priority list right now, so I'd say it will be a few months until I get to it, unless someone else steps up
2010-08-28 00:49 <wolfspraul> well but for discussions like the one between you and wpwrak, I think it's really great to keep them archived :-)
2010-08-28 00:49 <DocScrutinizer> wolfspraul: put logbots /ignore list to purpose ;-D
2010-08-28 00:50 <wolfspraul> so I hope you won't make use of the opt-out feature once we have it
2010-08-28 00:50 <wolfspraul> DocScrutinizer: does freenode already have something that prevents your msgs from going to a particular (logging) nick?
2010-08-28 00:50 <DocScrutinizer> now for ti.com
2010-08-28 00:51 <DocScrutinizer> wolfspraul: I'm agnostic of the particular ways /ignore is implemented, but wouldn't be surprised it's server side
2010-08-28 00:51 <DocScrutinizer> /mode #qi-hardware +i wolfspraul
2010-08-28 00:51 <wolfspraul> k I'll look into it one day
2010-08-28 00:52 <DocScrutinizer> maybe
2010-08-28 00:52 <DocScrutinizer> can't remember right now
2010-08-28 00:52 <DocScrutinizer> mompls
2010-08-28 00:52 <wpwrak> there's no feature under the sun someone hasn't implemented in irc yet ;-)
2010-08-28 00:53 <DocScrutinizer> http://toxin.jottit.com/freenode
2010-08-28 00:54 <wpwrak> hmm, interesting. ti have an 8051 with usb and transceiver. that's the one the used for the antenna circuit. rather nice.
2010-08-28 00:55 <DocScrutinizer> hmm, http://toxin.jottit.com/irc_commands suggests /ignore is a UA command
2010-08-28 00:56 <wpwrak> ah, but it's one if quirky non-ieee 802.15.4 designs. darn.
2010-08-28 00:56 <DocScrutinizer> darn, closed irclog, wpwrak can you repost the ti url please?
2010-08-28 00:56 <wpwrak> | ti's design [1] feeds the antenna from the long side and has free space on the left. [1] http://focus.ti.com/lit/an/swra117d/swra117d.pdf
2010-08-28 00:56 <wpwrak> | i have the left side blocked with the circuit and the feed line goes around. not sure how horrible this is in the general scale of things.
2010-08-28 00:57 <wpwrak> | of course, nobody has a useful antenna design that's fed from the short side :-(
2010-08-28 00:57 <wpwrak> these were the last three lines
2010-08-28 00:57 <DocScrutinizer> what's short side and left side in your world?
2010-08-28 00:59 <wpwrak> if you look at my pcb pictures, left is left, etc.
2010-08-28 00:59 <DocScrutinizer> on a general note - PCB antenna designs are very sensitive to *any* change of geometry
2010-08-28 00:59 <wpwrak> left and right are short, top and bottom are long.
2010-08-28 00:59 <wpwrak> i didn't touch the geometry. just the surroundings :)
2010-08-28 01:00 <DocScrutinizer> you need to keep the whole design incl feedpoint and adjacent gndplanes
2010-08-28 01:02 <DocScrutinizer> e.g you can't add gndplanes to top, right or bottom, and you need to keep the full gndplane (edge, at least) on left side
2010-08-28 01:02 <DocScrutinizer> sorry didn't look at your design
2010-08-28 01:03 <DocScrutinizer> now I did. Nope that won't pan out
2010-08-28 01:04 <DocScrutinizer> the GND plane parallel to the short fat antenna branch is way too close
2010-08-28 01:04 <wpwrak> hmm. feed and all that are where they should be. how close can i go with gnd on the left ?
2010-08-28 01:04 <wpwrak> and would it help if i put the gnd zone at, say, a 45 deg angle ?
2010-08-28 01:06 <DocScrutinizer> max ~1.5 of the general structure detal size, I'd guess from my guts. So about  size of one of the "squares" of meander * 1.5
2010-08-28 01:06 <wpwrak> also, does the gnd that's too close affect rx and tx in about the same way or does one suffer a lot more ? (e.g., i would suspect that it hurts tx a lot more)
2010-08-28 01:07 <wpwrak> okay, that should be feasible. parallel to the short side or angled ?
2010-08-28 01:08 <DocScrutinizer> sorry, please rephrase
2010-08-28 01:08 <DocScrutinizer> (affect) both virtually same
2010-08-28 01:08 <wpwrak> 1) in the current design, with the gnd too close to the antenna, would that gnd distort/weaken emissions and receptions roughly in the same way ?
2010-08-28 01:09 <DocScrutinizer> (affect) both virtually same
2010-08-28 01:10 <wpwrak> 2) we assume the lower left corner of the antenna is at coordinates (0, 0), should the edge if ground plane run parallel to the short side, (-d, 0) to (-d, h) ?
2010-08-28 01:10 <wpwrak> d = distance gnd plane to antenna. h = "height" of antenna
2010-08-28 01:11 <wpwrak> or would it be better if i make it (-d+h) to (-d, h) ? i.e., at a 45 deg angle, but the closest point of the gnd plane would be closer to the antenna this way
2010-08-28 01:12 <DocScrutinizer> parallel
2010-08-28 01:12 <wpwrak> kewl. that's easier :)
2010-08-28 01:14 <wpwrak> btw, i don't think the crystal in the board on the picture worked :) had to reflow the critter for better alignment. first time i actually had some successful use for my hot air pen :)
2010-08-28 01:14 <DocScrutinizer> Small changes of the antenna dimensions may have large impact on the performance. Therefore it is strongly recommended to make an exact copy of the reference design to achieve optimum performance
2010-08-28 01:14 <DocScrutinizer> </quote>
2010-08-28 01:15 <wpwrak> yup, that's what i did
2010-08-28 01:15 <DocScrutinizer> watch D1, D4 and GND Layer 2
2010-08-28 01:17 <wpwrak> http://www.almesberger.net/misc/ben/wpan/atrf.pdf
2010-08-28 01:18 <wpwrak> (hmm, need to add a filter for backup files to fpd2pdf)
2010-08-28 01:18 <wpwrak> d4 ?
2010-08-28 01:19 <DocScrutinizer> also amazing: even while there's (of course) no gndplane under the antenna structure, still they recommend >> It is also recommended to use the same thickness and type of PCB material as used in the reference design. Information about the PCB can be found in a separate readme file included in the reference design. To compensate for a thicker/thinner PCB the antenna could be made slightly shorter/longer.<<
2010-08-28 01:19 <DocScrutinizer> your design is missing upper gnd plane
2010-08-28 01:21 <wpwrak> ah ... D1 as a dimension
2010-08-28 01:22 <DocScrutinizer> page 4, figure 3
2010-08-28 01:22 <wpwrak> i keep that clearance. but it's a lot less than what you're suggesting
2010-08-28 01:22 <wpwrak> the upper gnd is a bit mysterious
2010-08-28 01:23 <wolfspraul> what if the board Werner is designing is integrated into another bigger pcb (the one we currently have behind the lcm)?
2010-08-28 01:23 <wolfspraul> if thickness matters - I think the PCB that currently is behind the LCM is rather thin
2010-08-28 01:23 <wpwrak> i read figure 3 as not having gnd there. but then, on the picture of their real board, there is a gnd plane
2010-08-28 01:24 <DocScrutinizer> >> The size of the ground plane affects the performance of the PCB antenna. Connecting the USB dongle to a computer increases the size of the ground plane and thus the performance is affected. Figure 5 shows how the performance is affected when the USB dongle is...<<
2010-08-28 01:24 <wpwrak> wolfspraul: it;s very close to the 0.8 mm i use
2010-08-28 01:24 <DocScrutinizer> (lot less than what you're suggesting) yup. Even I can fail
2010-08-28 01:24 <wpwrak> DocScrutinizer: (size of gnd plane) yeah. big computer = better. that's why i want to be close to the lcm. it's not much but better than nothing.
2010-08-28 01:26 <wpwrak> DocScrutinizer: so you think keeping it that close is acceptable ? ti don't say specifically that it's okay to put something nearby. they just strongly suggest that nothing should be in that area.
2010-08-28 01:27 <wpwrak> or, rather, nothing but the pcb dielectric
2010-08-28 01:27 <DocScrutinizer> I'd keep it away, though in theory it might be irrelevant, given D1 keeps minimum of 0.50mm
2010-08-28 01:28 <DocScrutinizer> in the end that fat trace has a GND via, which I wasn't aware of first instance
2010-08-28 01:28 <wpwrak> okay. a few more mm can't hurt anyway.
2010-08-28 01:29 <DocScrutinizer> so parasitary capacitance to nearby gndplane might be less of an issue
2010-08-28 01:29 <wpwrak> (gnd via) rf is spooky to measure. all things are "shorted" to ground ;-)
2010-08-28 01:29 <wpwrak> (to measure with a digital multimeter)
2010-08-28 01:29 <DocScrutinizer> yeah X-P
2010-08-28 01:30 <DocScrutinizer> put your DMM in your attik as long as dealing with RF
2010-08-28 01:30 <DocScrutinizer> useless equipment
2010-08-28 01:30 <wpwrak> okay, so we have the transmission line and the upper ground plane. i also need to check their pcb thickness. i have it something in the back of my head that 0.8 mm are okay, but i'm now no longer sure if i took that from ti or just from compatibility with the lcm's pcb.
2010-08-28 01:31 <wpwrak> it's still good for testing traces ;-)
2010-08-28 01:33 <DocScrutinizer> wpwrak: you can have a short (about 2..3 times trace width) parallel to gndplane 'serife' at long end of antenna (like a L ) and then dremel away successively until antenna is tuned
2010-08-28 01:34 <DocScrutinizer> (next to "W2 <->")
2010-08-28 01:34 <wpwrak> you mean extending from the end of the antenna towards the right ?
2010-08-28 01:34 <DocScrutinizer> yep
2010-08-28 01:35 <DocScrutinizer> next to arrow tips of W2 and L1, to the right, length suggested 2 * W2
2010-08-28 01:36 <DocScrutinizer> parallel to "<->" ow D3
2010-08-28 01:36 <DocScrutinizer> of*
2010-08-28 01:37 <wpwrak> and now the big question: how do i tell when my antenna is tuned ? :) that is, with my modest measurement apparatus ?
2010-08-28 01:37 <DocScrutinizer> that's the most challenging part, and the reason we got antenna houses doing that for us ;-D
2010-08-28 01:38 <wpwrak> grmbl :)
2010-08-28 01:38 <emeb> wpwrak: what test equipment do you have?
2010-08-28 01:38 <DocScrutinizer> probably measuring exact dBm at a given never changing distance with a good receiver will do
2010-08-28 01:39 <wpwrak> i have an usrp that can operate at 2.4 GHz and 5 Ghz. so i should be able to do *something* at carrier and 1st harmonic
2010-08-28 01:39 <wpwrak> no calibrated antenna, though
2010-08-28 01:39 <DocScrutinizer> 1st harmonic - nevermind
2010-08-28 01:39 <emeb> that's actually not bad...
2010-08-28 01:39 <DocScrutinizer> calib rcv antenna - nvm
2010-08-28 01:39 <wpwrak> (1st harm.) gcc and etsi love that one ;)
2010-08-28 01:40 <DocScrutinizer> just make sure you got a clearly defined never changing testbed
2010-08-28 01:40 <wpwrak> (1st harm) also, the more power i see there, the less i'll have where i want it to be :)
2010-08-28 01:40 <DocScrutinizer> wpwrak: (1st harmonic) there's just so much you can do about it anyway
2010-08-28 01:40 <wpwrak> that's where your pi filter comes into play :)
2010-08-28 01:41 <DocScrutinizer> not exactly
2010-08-28 01:41 <DocScrutinizer> Pi filters are Z matchers
2010-08-28 01:41 <DocScrutinizer> not filters
2010-08-28 01:42 <DocScrutinizer> first approach at least - of course they are also lowpass
2010-08-28 01:43 <DocScrutinizer> wpwrak: also note there's antenna detuning even by plastic enclosures, so final antenna tuning has to be done in final product anyway
2010-08-28 01:43 <wpwrak> the one i have is used as such. to make up for all the mistakes atmel made in their balun :)
2010-08-28 01:44 <DocScrutinizer> humm, I see
2010-08-28 01:44 <wpwrak> DocScrutinizer: exactly why i don't see wolfgang avoid rf issues by using modules :)
2010-08-28 01:45 <DocScrutinizer> the issue doesn't get much better by using a module. It will see same detuning :-P
2010-08-28 01:46 <wpwrak> yup :)
2010-08-28 01:46 <wpwrak> and then you're back to tweaking little caps and inductors while staring at your measurement equipment :)
2010-08-28 01:47 <emeb> everyone who works RF has to do that...
2010-08-28 01:48 <wpwrak> yup. there's no hiding place.
2010-08-28 01:49 <emeb> just need to avoid the iPhone 'death grip' :)
2010-08-28 01:49 <DocScrutinizer> damn, a nice antenna design: 350MHz bandwidth
2010-08-28 01:50 <emeb> how much BW is needed for the wpan? - only a few 100kHz, no?
2010-08-28 01:51 <wpwrak> the band is ~100 MHz
2010-08-28 01:51 <wpwrak> not quite sure about the chanbnel width
2010-08-28 01:51 <emeb> and the chip can tune over the whole band?
2010-08-28 01:51 <wpwrak> yup
2010-08-28 01:52 <emeb> kewl
2010-08-28 01:52 <wpwrak> it's like wifi
2010-08-28 01:52 <wpwrak> 2405 - 2480 MHz
2010-08-28 01:53 <wpwrak> channel spacing is 5 MHz
2010-08-28 01:53 <emeb> wow - more than I thought...
2010-08-28 01:53 <wpwrak> data rate is 250 kbps
2010-08-28 01:54 <DocScrutinizer> muses idly what WPAN might be at all
2010-08-28 01:54 <emeb> so there's a lot of dead air between channels.
2010-08-28 01:54 <wpwrak> chip rate 2 Mchips/s
2010-08-28 01:54 <DocScrutinizer> emeb: for sure not
2010-08-28 01:54 <emeb> ?? didn't realize it was dsss
2010-08-28 01:54 <wpwrak> wireless personal area network. basically a bubble arund you with ~10 m radius
2010-08-28 01:55 <emeb> guess I was still thinking the FM stuff that HopeRF was using...
2010-08-28 01:55 <DocScrutinizer> what's it worth for?
2010-08-28 01:55 <wpwrak> not sure about modulation details yet. that's still on mt reading list
2010-08-28 01:56 <wpwrak> emeb: all the sub-ghz stuff is basically unusable for us. way too many regulatory restrictions.
2010-08-28 01:57 <emeb> gotcha.
2010-08-28 01:57 <wpwrak> emeb: such as duty cycle. 1 s per hour or so, in some of the more extreme cases.
2010-08-28 01:57 <emeb> heh - not really useful
2010-08-28 01:57 <DocScrutinizer> hrhrhrr
2010-08-28 02:06 <emeb> wow - those at86rf230 chips are cheap - $2.27 in 100qty from Digi-key
2010-08-28 02:07 <wpwrak> the cc2520 is also not bad. according to ti, as low as $1,95/1000
2010-08-28 02:07 <wpwrak> so both are interesting
2010-08-28 02:08 <DocScrutinizer> wpwrak: I strongly suggest to also review the documentation of CC2511 reference design, schematics and all. Also to find out about mystery of that "upper GNDplane"
2010-08-28 02:08 <wpwrak> ti's has a few more features, such as more buffers. atmel has onlt one, shared between rx/tx/host. kinda like the 3c501 ethernet :)
2010-08-28 02:08 <emeb> so are you still undecided which chip to use?
2010-08-28 02:09 <wpwrak> yup, good idea. there are also a few mystery components next to the antenna
2010-08-28 02:09 <DocScrutinizer> exactly
2010-08-28 02:09 <wpwrak> emeb: they both look attractive
2010-08-28 02:10 <DocScrutinizer> I'd expect to find some words about "making antenna shorter/longer" in the included readme
2010-08-28 02:10 <emeb> hmm - Digi-Key's 100pc price for the CC2511 is $6.10
2010-08-28 02:11 <emeb> $4.73 for the CC2520
2010-08-28 02:12 <wpwrak> 2511 is mcu + usb + rf
2010-08-28 02:12 <wpwrak> 2520 is just rf, like the at86rf230
2010-08-28 02:14 <emeb> atmel datasheet is pretty sparse on RF details
2010-08-28 02:17 <wpwrak> emeb: then try to find the impedance in ti's ...
2010-08-28 02:17 <emeb> :)
2010-08-28 02:18 <emeb> section 9.1 of the cc2520 ds says "high impedance". What more do you want?
2010-08-28 02:20 <wpwrak> good luck finding the rest :)
2010-08-28 02:25 <emeb> nice chatting - gn
2010-08-28 02:26 <wpwrak> DocScrutinizer: any other "red flags" in my design ? the whole mcu side and the crystal will go away when putting all this into the ben
2010-08-28 02:26 <DocScrutinizer> wpwrak: I missed the point of WPAN advantages over more established protocols like e.g BT PAN
2010-08-28 02:27 <DocScrutinizer> (red flag) I gather the crappy SMT only non-thruhole USB receptacle will go away as well
2010-08-28 02:27 <wpwrak> openness. basically everything WLAN or even BT is under NDA. and sometimes you can't even buy the chips/modules. or they're excessively expensive.
2010-08-28 02:27 <DocScrutinizer> :-(
2010-08-28 02:28 <wpwrak> hey, everybody uses that receptacle ;-) and i soldered it well :)
2010-08-28 02:28 <DocScrutinizer> what an epic fail
2010-08-28 02:29 <wpwrak> and yes, it'll go away. the idea is to basiclly cut at the two v-shaped dents. and of course remove the crystal. didn't know for sure what to with it when i designed the board
2010-08-28 02:29 <DocScrutinizer> (USB) yeah, and N900 returns/repairs/MIAs are legion, due to micro-USB rcptcl coming off
2010-08-28 02:29 <wpwrak> so far, _my_ usb receptacles are holding :)
2010-08-28 02:30 <wpwrak> but it's nice to hear that not only OM screwed up their usb :)
2010-08-28 02:30 <DocScrutinizer> industry should specify drop-tests to be done -mandatory - with cables attached
2010-08-28 02:30 <wpwrak> ;-)
2010-08-28 02:31 <DocScrutinizer> the whole USB receptacle and plugs shit is a botch, at best
2010-08-28 02:31 <wpwrak> btw, the receptacle i used in idbg is pretty much indestructible. it's mounted inside the board plane, so there's no lever on the pull/push forces. as long as the pcb holds, that thing stays there.
2010-08-28 02:32 <DocScrutinizer> genearlly receptacles must be mounted to solid case, and connected to PCB by flexible  / detachable connection
2010-08-28 02:32 <wpwrak> here;s the critter: http://www.almesberger.net/misc/ben/idbg-v1-pcb.jpg
2010-08-28 02:32 <wpwrak> http://www.almesberger.net/misc/ben/idbg-v1-side.jpg
2010-08-28 02:33 <DocScrutinizer> yup, that's another viable way to avoid it breaking on your first sneezing
2010-08-28 02:33 <wpwrak> also note the six (!) solder pads. i think nokia wouldn't have much trouble if they had used this one :)
2010-08-28 02:34 <DocScrutinizer> forget it! no matter what breaks, whether solder points or clue holding copper traces to base epoxy or the whole PCBA cracks. It's a flimsy design - by design
2010-08-28 02:34 <DocScrutinizer> s/clue/glue
2010-08-28 02:35 <wpwrak> yeah, pcb cracking is nasty
2010-08-28 02:35 <wpwrak> the proble is that you can't produce case-mounted connectors nearly as cheaply as pcb-mounted ones
2010-08-28 02:35 <DocScrutinizer> never will stand bending/torque forces >200Ncm
2010-08-28 02:36 <DocScrutinizer> err 2Ncm?
2010-08-28 02:36 <wpwrak> 200 Ncm is a lot :)
2010-08-28 02:36 <DocScrutinizer> 1Newton == 100g
2010-08-28 02:36 <DocScrutinizer> no?
2010-08-28 02:36 <wpwrak> yes
2010-08-28 02:36 <DocScrutinizer> so make that 2Ncm
2010-08-28 02:37 <wpwrak> 2 Ncm should be fine
2010-08-28 02:37 <DocScrutinizer> i'd have used pcm but that's quite uncommon and ambiguous
2010-08-28 02:37 <wpwrak> that's one chocolate suspended from the end of a usb connector
2010-08-28 02:37 <DocScrutinizer> exactly
2010-08-28 02:38 <DocScrutinizer> and you'll exceed that easily, in a lot of everyday situations
2010-08-28 02:38 <wpwrak> agreed
2010-08-28 02:38 <DocScrutinizer> like dropping device on connector, or just putting it on sofy and then sitting on it
2010-08-28 02:38 <DocScrutinizer> sofa*
2010-08-28 02:38 <wpwrak> don't sit on your computers ! :)
2010-08-28 02:39 <DocScrutinizer> I bet a lot of less coordinated people will exceed that on mere unplugging
2010-08-28 02:39 <wpwrak> maybe a sofa-compatible computer would need a big capacitative sensor, to detect the approaching of the owner's arse ;-)
2010-08-28 02:40 <DocScrutinizer> or trip over the wire of charger - bang, dead
2010-08-28 02:40 <wpwrak> yes, i think plug/unplug forces can be quite large
2010-08-28 02:40 <wpwrak> most things don't break quite so easily
2010-08-28 02:40 <DocScrutinizer> USB receptacles do, esp the SMT type
2010-08-28 02:42 <wpwrak> hmm, i have stuff fall down, too. nothing broke so far. granted, i don't tie them to my car and drag them across town ...
2010-08-28 02:42 <DocScrutinizer> to make matters worse, it seems a lot of micro-USB come with excessive plug forces, by design
2010-08-28 02:42 <wpwrak> yup. micro-usb wants a good push
2010-08-28 02:44 <DocScrutinizer> honestly, micro-USB rcptcl should have its own mounting PCB, fixed to case, and any sort of wire or spring contacting to main PCB
2010-08-28 02:44 <wpwrak> good luck with that proposal :-)
2010-08-28 02:46 <DocScrutinizer> look at N810 power connector (2mm barrel) or all the Nxxx series AV/headset connector. Those are nice plastic things with a number of goldplated springs to contact to pads on PCB
2010-08-28 02:46 <DocScrutinizer> case has a recession to hold the thing mechanically, a 'bay'
2010-08-28 02:47 <wpwrak> ah, they're spring-connected ? nice
2010-08-28 02:47 <DocScrutinizer> can't see fundamental obstacles to implement USB that way
2010-08-28 02:48 <wpwrak> contact spacing perhaps ?
2010-08-28 02:48 <DocScrutinizer> bah
2010-08-28 02:48 <DocScrutinizer> look there, the golden thing at right (6 contacts): http://people.openmoko.org/joerg/n900/images/IMG_1939.JPG
2010-08-28 02:48 <DocScrutinizer> AV connector
2010-08-28 02:49 <DocScrutinizer> (sorry for blurr)
2010-08-28 02:49 <wpwrak> ah, not bad
2010-08-28 02:49 <wpwrak> still bigger than usb, i think, but smaller than i would have expected
2010-08-28 02:50 <DocScrutinizer> oops N810 has SMT AV
2010-08-28 02:51 <wpwrak> there goes the neighbourhood :)
2010-08-28 02:51 <DocScrutinizer> http://people.openmoko.org/joerg/N810-disassembly/n810_disassembly/snc00297_jpg.jpeg.html for power barrel spring type
2010-08-28 02:52 <wpwrak> kinda biggish, if considering usb size
2010-08-28 02:52 <DocScrutinizer> *shrug*
2010-08-28 02:52 <DocScrutinizer> it's not like those devices are <2% air inside
2010-08-28 02:53 <wpwrak> the usb receptacle does look a bit fragile, though
2010-08-28 02:54 <wpwrak> only half the pads large, the other(s) already quite small
2010-08-28 02:54 <DocScrutinizer> flimsy crap
2010-08-28 02:54 <DocScrutinizer> never can work decently
2010-08-28 02:55 <DocScrutinizer> I mean, thru hole would give at least a minimum of ruggedness
2010-08-28 02:55 <DocScrutinizer> spring load contacts and fixed in a bay would be optimum
2010-08-28 02:57 <DocScrutinizer> you literally had to break the case to ruin the receptacle, and even then you can just get a spare case which is supposed to be much cheaper than spare main PCBA
2010-08-28 02:57 <wpwrak> i thnk large enough pads should make it work okay for smt too
2010-08-28 02:57 <wpwrak> just tiny pads don't work. well, ironically, often it's even the solder than breaks, not the pad
2010-08-28 02:58 <DocScrutinizer> yup
2010-08-28 02:58 <DocScrutinizer> luckily
2010-08-28 02:58 <wpwrak> yes :)
2010-08-28 02:58 <DocScrutinizer> it's a botch, and it stays that way
2010-08-28 02:59 <DocScrutinizer> could be done better
2010-08-28 02:59 <DocScrutinizer> just like most pushbutton designs
2010-08-28 02:59 <DocScrutinizer> full load of force to the switching element... no wonder it breaks on first hard push
2010-08-28 03:00 <DocScrutinizer> why not have a latch or something where the plastic knob movement is limited hard, and pushing the switch with a "spring" designed into the knob plastic
2010-08-28 03:01 <DocScrutinizer> this way you never can break the switch, unless you poke *through* the plastic knob
2010-08-28 03:02 <wpwrak> hmm. patent it :)
2010-08-28 03:03 <DocScrutinizer> bah
2010-08-28 03:03 <DocScrutinizer> I'd rather love to see it *used* than patented
2010-08-28 03:03 <wpwrak> you could replace the spring with some silicone
2010-08-28 03:03 <DocScrutinizer> sure
2010-08-28 03:04 <DocScrutinizer> though this is harder to assemble, one component more
2010-08-28 03:04 <wpwrak> give the button four little feet. then you can use an off-the shelf dome.
2010-08-28 03:04 <DocScrutinizer> exactly
2010-08-28 03:04 <wpwrak> you'd just fill the keycap with the silicone
2010-08-28 03:04 <wpwrak> easier to do then placing a spring
2010-08-28 03:05 <wpwrak> well, scratch the silicone
2010-08-28 03:05 <DocScrutinizer> I thought of making the 'spring' just a thin lever - part of the plastic of knob
2010-08-28 03:05 <wpwrak> just a button with feet to terminate the movement will do
2010-08-28 03:06 <DocScrutinizer> nope
2010-08-28 03:06 <DocScrutinizer> can't manufacture that exact enough
2010-08-28 03:06 <wpwrak> the dome also allows for some tolerance
2010-08-28 03:07 <DocScrutinizer> headroom from 'click point' to maximum push in of a smt switch is <0.05 mm
2010-08-28 03:07 <DocScrutinizer> a dome type spring switch has no such headroom at all
2010-08-28 03:08 <wpwrak> hmm. lemme check this ...
2010-08-28 03:09 <DocScrutinizer> you need to push it down all the way until the metal dome touches the PCB pad. In that moment contact and limiting of movement are same thing
2010-08-28 03:09 <DocScrutinizer> I was thinking of side force operated type smt switches, like in FR
2010-08-28 03:10 <DocScrutinizer> though the silicone thing + feet works for dome type as well
2010-08-28 03:11 <DocScrutinizer> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=P10850SCT-ND FR AUX button
2010-08-28 03:12 <DocScrutinizer> sure like hell will come off, just needs enough operation force
2010-08-28 03:13 <wpwrak> hmm, dome data sheet doesn't say how far it can travel once active. there must be some tolerance.
2010-08-28 03:14 <DocScrutinizer> there isn't by design
2010-08-28 03:14 <DocScrutinizer> (well axcept for how much you can compress the metal of the dome :-P)
2010-08-28 03:15 <DocScrutinizer> or the PCB and pad
2010-08-28 03:17 <wpwrak> yup. that's what i was thinking of
2010-08-28 03:17 <DocScrutinizer> and that are, incidentally, exactly the two failure patterns you see on dome sheet kbds like the one on N810: puncture the pad by excessive force, so there's no more contact when dome pressed down to the plain epoxy - and deformation of the dome spring, so it loses its properties
2010-08-28 03:18 <wpwrak> both should need quite a bit of force ...
2010-08-28 03:18 <DocScrutinizer> often less than you might think
2010-08-28 03:18 <wpwrak> you also have the dome's base that may be flexible
2010-08-28 03:18 <wpwrak> http://www.components.omron.com/components/web/PDFLIB.nsf/0/DBD9E60DE8D27D6785257201007DD6A3/$file/B3D_1109.pdf
2010-08-28 03:19 <wpwrak> this one has a PUR ring
2010-08-28 03:19 <DocScrutinizer> heh
2010-08-28 03:19 <wpwrak> ah, but the metal is inside, so, doesn't help
2010-08-28 03:20 <DocScrutinizer> if patenting would help to propagate it into industry, I'd for sure do it. But I'm sure it'd be rather contraproductive
2010-08-28 03:22 <DocScrutinizer> anyway, 9'o saturday morning. The time they run their tests on TV how far the idiocy may be pushed on the customers
2010-08-28 03:22 <DocScrutinizer> mustn't miss that :-P
2010-08-28 03:23 <DocScrutinizer> also *yawn*
2010-08-28 03:24 <wpwrak> ;-)) yeah, soon 4:30 here. may be a good moment for a nap.
2010-08-28 03:24 <wpwrak> thanks a lot for your rf suggestions !
2010-08-28 03:25 <wpwrak> that gives me hope the next version will perform a bit less crappy than the current one :)
2010-08-28 03:27 <DocScrutinizer> always a please, yw
2010-08-28 03:28 <DocScrutinizer> pleasure even
2010-08-28 03:40 <wpwrak> i'll try to have more difficult questions the next time :)
2010-08-28 03:57 <roh> about connectors and so.. if you want to know how to _really_ do that.. check out a lenovo T60 power plug
2010-08-28 03:58 <roh> they put the socket into a 'cave' inside the case which encloses it from all sides, a hole to the back which it cant fall through (rim) and multiple wires (4 in total, 2 for each pin in parallel since its power) go to the board and are connected with a 4 pin minimolex or so
2010-08-28 03:59 <roh> means you can a) exchange the power-socket (big barrel type) seperately, and it can 'wobble' a bit. make breaking out of the socket basically impossible, and also breaking it off a mainboard or so.
2010-08-28 03:59 <roh> great design.
2010-08-28 04:01 <roh> i guess one could mount a usb that way. put it on a pcb which is only 2-3mm wider than the socket, use 4 wires to the main pcb, put the whole thing in a 'recessed' indention in one of the case parts and fixate it by putting the other casing half over it. no more broken pcbs
2010-08-28 04:37 <kyak> unclouded: nightsky 20100827 is working fine!
2010-08-28 04:38 <kyak> is a great piece of software :)
2010-08-28 04:39 <kyak> unclouded: how do you zoom in/out? it's bound to F11/F12
2010-08-28 05:27 <unclouded> kyak: it says F11 and F12 but its the volume up and down keys in SDL
2010-08-28 06:06 <kyak> unclouded: hm, you mean Vol Up and Down
2010-08-28 06:06 <kyak> yeah, works great :) thanks!
2010-08-28 06:06 <unclouded> yes.  they turn up as F11 and F12 in SDL.  I should adjust the help text for the NanoNote though
2010-08-28 06:06 <kyak> unclouded: do you know how i can see the Sky in specific date/time?
2010-08-28 06:06 <kyak> without changin system date/time
2010-08-28 06:07 <kyak> unclouded: maybe the F1 help text in source code? Definitely should be patched
2010-08-28 06:07 <unclouded> not without editing the source
2010-08-28 06:08 <kyak> F11/F12 are bound very conveniently .. i don't know if this is just a conicidence
2010-08-28 06:08 <kyak> unclouded: would be better if after pressing F1 it would indicate that zoom in/out keys are VolUp and VolDown
2010-08-28 06:09 <unclouded> no coincidence.  it was written for the NanoNote
2010-08-28 06:09 <kyak> heh, great
2010-08-28 06:10 <unclouded> if you wanted to edit the source to show the sky at different times you want the lines that looks like: model.when_updated = time( NULL); in the update_main() method in main.c
2010-08-28 06:11 <unclouded> time(NULL) returns the time now.  using a different value will show the sky at the time represented by that different value
2010-08-28 06:11 <kyak> i see.. thanks for the hint
2010-08-28 06:11 <kyak> maybe for starters it can read this from config file
2010-08-28 06:12 <kyak> reading from user input would be harder
2010-08-28 06:14 <kyak> unclouded: i see you've updated version on SF
2010-08-28 06:17 <unclouded> the latest version only adds the ability to resize the window and build on Mac OS X, nothing new for the NN
2010-08-28 06:20 <kyak> do you plan to put more effort into nightsky? for example, implement possibility to search objects?
2010-08-28 06:22 <unclouded> not sure yet
2010-08-28 06:24 <kyak> what exists now is already great though :)
2010-08-28 06:26 <unclouded> to type stuff in it would have to have a primitive text field: type letters, backspace, delete, cursor, etc. but otherwise searching for an object would be a useful feature
2010-08-28 06:27 <kyak> yeah, it would be.. searching for objects and setting arbitrary dates/times
2010-08-28 06:45 <unclouded> although out of the 10,000 odd brightest objects, only 230 have common names
2010-08-28 14:51 <kristianpaul> http://screenshots.debian.net/packages?debtag=uitoolkit%3A%3Ancurses
2010-08-28 14:51 <kristianpaul> nice screenshot
2010-08-28 14:56 <wpwrak> hmm. needs a hierarchy by topic. cutest on top. there should also be an "install me right now" link :)
2010-08-28 14:57 <wpwrak> but yes, screenshots are important. we're very visual animals. that won't go away anytime soon :)
2010-08-28 14:57 <wpwrak> ascii art ski jumping. oh dead ;-)
2010-08-28 14:57 <wpwrak> deaR even
2010-08-28 14:59 <viric> kristianpaul: through that I discovered 'asc'! I go building it
2010-08-28 15:00 <kristianpaul> wpwrak: indeed topic lacking
2010-08-28 17:26 <wpwrak> grr. git log --follow  follows renames only into the past, not into the future :-(
2010-08-28 17:36 <wpwrak> this is going to be messy ...
2010-08-28 18:30 <rafa__> are news around?
2010-08-28 18:30 <rafa__> hi
2010-08-28 18:30 <rafa__> :)
2010-08-28 20:37 <wpwrak> rafa__: everybody seems to have a relaxing saturday:)
2010-08-28 20:38 <viric> I just discovered ufoai :)
2010-08-28 20:38 <wolfspraul> rafa__: you online? where are you?
2010-08-28 20:42 <wpwrak> he should still be in barcelona
2010-08-28 20:46 <viric> hm I live near Barcelona
2010-08-28 20:46 <viric> 100km away
2010-08-28 20:48 <wolfspraul> wpwrak: nice, so he made it through immigration :-)
2010-08-28 20:49 <wpwrak> wolfspraul: yeah. apparently they only had a quick look at the passport. didn't even want to see all the stuff they had prepared.
2010-08-28 20:50 <wolfspraul> that's how it should be
2010-08-28 20:51 <wpwrak> yes, indeed
2010-08-28 20:54 <rafa__> wolfspraul: hey!
2010-08-28 20:55 <rafa__> yes, we are in barcelona!
2010-08-28 20:55 <rafa__> we also met tuxbrain and we had some nice relaxing afternoonn talking
2010-08-28 20:55 <wpwrak> wolfspraul: will be interesting to find out what chip hoperf picked. it has a few unique magic numbers that only appear in their data sheet, according to google
2010-08-28 20:56 <wpwrak> things like 0xD99E8621 and 0xFFFFFEF7CF208104082041
2010-08-28 20:56 <rafa__> wolfspraul: the airport polices just check my face against passport. and i looks like and good england boy right now.. without beard and with a reallyy short haiir
2010-08-28 20:57 <rafa__> and i look like a good..
2010-08-28 20:57 <rafa__> :)
2010-08-28 20:58 <wpwrak> rafa: ah, you disguised yourself as skinhead ;-)
2010-08-28 20:58 <rafa__> let me show you a photo working with tuxbrain
2010-08-28 20:58 <rafa__> ..
2010-08-28 20:58 <rafa__> wpwrak: haha... nono. like a good boy.. skinhead is a little bad boy i guess
2010-08-28 20:59 <rafa__> well, i have beard again.. that is fast
2010-08-28 20:59 <rafa__> :P
2010-08-28 21:02 <rafa__> wpwrak: anyway, i do not rely in the spanish airport police yet.. aaand i feel the same when i need to get in to spain again after jlime meeting
2010-08-28 21:04 <rafa__> when i was there.. the police man was so tired he seemed... but i was seeing that other people started to have problems with other polices
2010-08-28 21:06 <rafa__> wpwrak: perhaps the strategy is to check which police man is wanting to leave the office :))
2010-08-28 21:08 <rafa__> hola gustavo ;)
2010-08-28 21:09 <wpwrak> rafa__: so another shave before returning to spain ? :) anyway, you'll return from a EU country. so there shouldn't be much in terms of border controls.
2010-08-28 21:12 <rafa__> ah yes? i do not know well the papers there.. if it asks about the "from" country  maybe yes, it should be like you say
2010-08-28 21:14 <wolfspraul> rafa__: wow great you are with David?
2010-08-28 21:14 <wpwrak> rafa__: maybe keep boarding passes and hotel receipts. that way, you can always prove that you're indeed on an fairly extensive trip.
2010-08-28 21:16 <wpwrak> rafa__: i don't quite remember how the airports deal with intra-EU immigration. in theory, there should be no control. but if passengers from EU can be mixed with passengers connecting from non-EU flights, then there would be controls.
2010-08-28 21:18 <rafa__> wolfspraul: it was great.. he and victor are really nice guys and very funny guys :D
2010-08-28 21:19 <rafa__> wolfspraul: wpwrak : http://fz.hobby-site.org/hp660lx/nn/working_at_tuxbrain.jpg
2010-08-28 21:19 <rafa__> i wrote the link manually, let me know if it works :P (i am chating with my hp palmtop)
2010-08-28 21:21 <wpwrak> empty beer glasses ?!?
2010-08-28 21:21 <rafa__> wpwrak: that was before to leave
2010-08-28 21:21 <rafa__> :)
2010-08-28 21:33 <wolfspraul> joshcryer: welcome to our copyleft hardware project :-)
2010-08-28 21:33 <wolfspraul> I wish one day we have a page like that Milkymist One SMT/DIP flow for a nice little ASIC manufacturing job...
2010-08-28 21:34 <wolfspraul> joshcryer: lekernel is the main force behind Milkymist, the channel is #milkymist on freenode
2010-08-28 21:50 <joshcryer> wolfspraul, thank you for the warm welcome. :)
2010-08-28 22:29 <kristianpaul> joshcryer: why milkymist is not free sofware?
2010-08-28 22:30 <kristianpaul> is code as we can see it, sure thee is a synteshis process
2010-08-28 22:30 <kristianpaul> sorry ask again i really want read your opinion
2010-08-28 22:31 <joshcryer> s/free software/free hardware/
2010-08-28 22:31 <joshcryer> uses Spartan-6 FPGA
2010-08-28 22:31 <joshcryer> Was not bashing, just thought it was not, exactly, what wolfspraul was talking about.
2010-08-28 22:31 <joshcryer> (with regards to freedombox)
2010-08-28 22:32 <kristianpaul> yeah sure the fpga is theere but at least we can implement free designs on it
2010-08-28 22:32 <joshcryer> Very true.
2010-08-28 22:32 <kristianpaul> hardware is not free by default ever
2010-08-28 22:32 <joshcryer> It's closer than FreedomBox.
2010-08-28 22:32 <joshcryer> Free as in freedom kristianpaul.
2010-08-28 22:32 <joshcryer> In English you do not say "Freedom Hardware."
2010-08-28 22:33 <kristianpaul> well you here thats good :)
2010-08-28 22:33 <wolfspraul> joshcryer: what is closer than FreedomBox?
2010-08-28 22:33 <wpwrak> don't "freedom fries" count ? ;-)
2010-08-28 22:33 <joshcryer> wolfspraul, Milkymist...
2010-08-28 22:33 <wolfspraul> Milkymist the IC design?
2010-08-28 22:34 <joshcryer> wolfspraul, yes, it incorporates non-free(dom) hardware.
2010-08-28 22:34 <joshcryer> Like FreedomBox does.
2010-08-28 22:35 <kristianpaul> is other level
2010-08-28 22:35 <wolfspraul> Milkymist is just an IC design, which on top of being entirely copyleft or BSD licensed, does go to great lengths to not build dependencies to proprietary vendor-specific FPGA extensions
2010-08-28 22:35 <wpwrak> joshcryer: so are you saying fpgas in general are out ? or just the spartan-6 ?
2010-08-28 22:36 <kristianpaul> we cant see hardware as just a big squared box and thats it
2010-08-28 22:36 <joshcryer> wpwrak, nah, wolfspraul even wants to move on to ASIC.
2010-08-28 22:36 <kristianpaul> there are leves we can achive freedon goals in some of then
2010-08-28 22:37 <kristianpaul> joshcryer: Having an ASIC doent mean we're done thereare propietary stuff required to make an ASIC
2010-08-28 22:37 <kristianpaul> so level by level...
2010-08-28 22:37 <joshcryer> wolfspraul, that's very fair enough. FreedomBox main competition is PlugComputer.
2010-08-28 22:38 <wpwrak> joshcryer: yup, but for now we're at fpgas. kinda more affordable :)
2010-08-28 22:38 <joshcryer> I did say that it was closer.
2010-08-28 22:38 <joshcryer> <joshcryer> It's closer than FreedomBox.
2010-08-28 22:38 <kristianpaul> and for what we really need "practical" freedom
2010-08-28 22:38 <joshcryer> But this discussion really split when I suggested that wolfspraul make himself an option for FreedomBox.
2010-08-28 22:39 <joshcryer> So FreedomBox 1.0 is PlugComputer or SheevaPlug, eventually it can become Milkymist-derived.
2010-08-28 22:39 <wpwrak> hmm, the mill has been enjoying more than a day off. time to give it something to do ... let's see ... the topmost plastic looks easy :) kinda useless, but all the rest i've left will be hell to mount.
2010-08-28 22:40 <wolfspraul> joshcryer: oh I misunderstood you then. you meant 'closer to freedom' not 'more closed' :-)
2010-08-28 22:41 <kristianpaul> joshcryer: so lets call it "free that non-free box"
2010-08-28 22:41 <kristianpaul> joshcryer: as we do when run free sofware on out computers
2010-08-28 22:41 <joshcryer> wolfspraul, apologies, English is a very difficult language, even for native speakers.
2010-08-28 22:42 <joshcryer> wolfspraul, I do sincerely hope you haven't ruled out being a FreedomBox platform some day though, as I think you have the right idea.
2010-08-28 22:42 <joshcryer> (I'm maybe a bit more optimistic / naive than most.)
2010-08-28 22:42 <wolfspraul> hard to compete with Marvell
2010-08-28 22:43 <joshcryer> Shame it's not atheros (packet injection). >:)
2010-08-28 22:43 <wolfspraul> they will integrate the CPU and Wi-Fi stuff, price will come down. maybe you will get that thing for 20 USD soon... who knows
2010-08-28 22:43 <kristianpaul> oh
2010-08-28 22:44 <joshcryer> So what, if you design ASIC and IC and we design PCB and cap/res. components you build the thing at materials cost (very very cheap).
2010-08-28 22:46 <joshcryer> wolfspraul, ShivaPlug is $125, V3.0 will likely be in same price range.
2010-08-28 22:46 <joshcryer> They should use Fonera but it's very limited (I am IRCing via my Fonera).
2010-08-28 22:46 <joshcryer> (And locked.)
2010-08-28 22:47 <kristianpaul> wolfspraul: why not Xburst + ethernet lilke a freedom box?
2010-08-28 22:48 <kristianpaul> Xburst chips are cheap hopefully can run server apps
2010-08-28 22:51 <wpwrak> i think a shivaplug-like device could make a useful platform for bringing MM to the masses. similar to a MM-based ben. basically take a design people are familiar with and totally change one key item.
2010-08-28 22:52 <wpwrak> however, a shivaplug-alike would also face regulatory issues. you may find it surprisingly difficult to ship such a thing to a lot of places.
2010-08-28 22:52 <joshcryer> Indeed, especially if it ran FreedomBox social networking cloud apps.
2010-08-28 22:52 <joshcryer> You destory facebook and fund free hardware designs, in one stroke.
2010-08-28 22:52 <joshcryer> >:D
2010-08-28 22:53 <wpwrak> well, the shipping will be fine. but then there are customs at the end, watching over local regulations.
2010-08-28 22:53 <wpwrak> joshcryer: "world domination, fast and on all fronts at once !" ;-)
2010-08-28 22:54 <joshcryer> That's my optimism speaking, btw. :)
2010-08-28 22:54 <joshcryer> What started it all was my mentioning my admiration of Moglen and someone posting a FreedomBox link and I'm afraid that wolfspraul thought we were saying it was better, but that was not the intention at all.
2010-08-28 22:54 <joshcryer> I quite like Qi-hardware now that I discovered it. :)
2010-08-28 23:00 <wpwrak> wolfspraul: btw, you'll notice that my "schematics diffs" often don't pick up a project from its beginning (happens in ben-wpan/atrf and xue). that's because not all the relevant top-level files (i.e., .pro and .sch) were committed from the start. so schhist2web starts looking at things beginning with the first commit but doesn't find anything it can use until later.
2010-08-28 23:01 <kristianpaul> well, i'mm off bed see ya :)
2010-08-28 23:02 <joshcryer> Later kristianpaul.
2010-08-28 23:02 <qi-bot> [commit] Andres Calderon: 5V out DC-DC added http://qi-hw.com/p/xue/d9b9c84
2010-08-28 23:03 <wolfspraul> wpwrak: well but that sounds like a feature not a bug, right?
2010-08-28 23:03 <wolfspraul> my main concern is that the scripts are robust
2010-08-28 23:03 <wolfspraul> never hang, never end in loops spamming the server disk space, those things
2010-08-28 23:05 <wpwrak> wolfspraul: it's a feature in the sense that the project was indeed not really usable at that point. it's a bug in the sense that there may be a history of changes we're missing. but i'd be a bit afraid of adding heuristics that move up in the history to cherry-pick files that may be missing. maybe add some mechanism for manual fixups in the future.
2010-08-28 23:05 <wpwrak> wolfspraul: (robust) time will tell ;-)
2010-08-28 23:06 <wpwrak> it would be good to run them in some sort of restricted environment. so that, even if something goes wrong, nothing horrible happens.
2010-08-28 23:07 <wpwrak> e.g., there are a few rm -rf in there. would be ugly if their arguments turn into a bare / by some twist of fate and the uid running all this actually can delete something valuable.
2010-08-28 23:09 <wpwrak> if someone was looking for a malicious exploit, there will almost certainly be something to find. after all, there are not only the shell scripts (shell being a fragile language when it comes to metacharacter exploits), but also git and eeschema. git has some interesting parsing heuristics that add a whole new set of meta-characters.
2010-08-28 23:10 <wpwrak> if we ignore malicious exploits, things should be a bit less rough. but i'd still take precautions.
2010-08-28 23:10 <wolfspraul> hmm
2010-08-28 23:11 <wpwrak> e.g., if wouldn't feel comfortable creating a new unprivileged user and running an rm -rf / as that user, then you probably don't want such a beast run wild
2010-08-28 23:11 <wolfspraul> we can ignore truly malicious exploits, but the 'restricted environment' still needs to be easily setup and maintainable
2010-08-28 23:11 <wolfspraul> I'll look into it
2010-08-28 23:12 <wolfspraul> wpwrak: would you feel comfortable running the script as an unprivileged user?
2010-08-28 23:12 <wpwrak> there are some forms of sandboxes that may be sufficient. package build processes often face the same challenges.
2010-08-28 23:12 <wpwrak> if your system is set up in a way that you wouldn't be afraid of your unprivileged user running rm -rf /, then yes
2010-08-28 23:15 <wpwrak> also, be warned that it can produce quite a lot of temporary output. e.g., xue has a cache of 3.7 GB
2010-08-28 23:17 <wpwrak> ben-wpan/atrf has 357 MB. ben-wpan/cntr only 32 MB (but the latter may get a bit bigger. there's still some bug somewhere hiding some things)
2010-08-28 23:18 <wpwrak> the cache is so big because it generates ppm files for all the schematics in all revisions. i can add an optimization for things that don't change later, though.
2010-08-28 23:20 <wpwrak> actually .. i could just use links ... let's see ...
2010-08-28 23:23 <wpwrak> for the things running crazy, you could just give it a generous cpu limit. maybe combined with a disk quota if you have that kind of stuff enabled.
2010-08-28 23:24 <wpwrak> for kicad, it also need some sort of X display. that can of course be some X server variant that doesn't need a head. vnc or such.
2010-08-28 23:25 <wpwrak> withvnc, you could also easily check what's wrong in case it hangs at some error dialog.
2010-08-28 23:31 <wolfspraul> ok got it
2010-08-28 23:33 <wpwrak> oh, and it can run in a pretty isolated environment if you want. no need to be able to write the repository or any other "valuable" data. at the end, you can just copy what it has generated from the output directory.
2010-08-28 23:33 <wpwrak> so even a VM that you scrap after use would be fine.
2010-08-28 23:36 <wpwrak> the only issue with recycling after use is that, if you lose the cache, it takes a while to process all the old commits. e.g., it needs about one minute for ben-wpan/atrf from a "cold" cache. after that, it's ~5 seconds if nothing has changed.
2010-08-28 23:36 <wpwrak> it's worse with xue. xue with a cold cache takes ~12 minutes. 16 seconds from up to date cache.
2010-08-28 23:38 <wpwrak> maybe i can make all this a bit faster when eliminating some of the rituals for unchanged files. unfortunately, it's hard to predict when a file may change or not. e.g., if the .sch is the same but a .lib or even the .pro has changed, the output could be different.
2010-08-28 23:38 <wolfspraul> don't go crazy, I think I need to move on the server now
2010-08-28 23:39 <wolfspraul> for Xue, the #1 thing that stood out last time still were the sheets that had no images at all, just an empty column
2010-08-28 23:40 <wpwrak> yup. that's the name tracking problem. it's a bit harder than i thought, because git won't tell me about renames in the past->present direction, only present->past.
2010-08-28 23:42 <qi-bot> [commit] Xiangfu Liu: test-memory-card.sh: cleanup the output message, modify by Adam http://qi-hw.com/p/nn-usb-fpga/b6f32d5
2010-08-28 23:43 <wolfspraul> xiangfu: the 8 and 16 gb cards still don't boot
2010-08-28 23:43 <wpwrak> there's also the problem that xue uses a3 while i expect a4. i need to poke around inside the .sch for this. the .ps generated by eeschema always claims it's a4 :-(
2010-08-28 23:44 <wolfspraul> can you send me a u-boot with some more on-screen logging? maybe also just some number at the end (shortly before the error message so it's still visible), so that I know for sure that I am booting with the right u-boot version
2010-08-28 23:44 <wolfspraul> or maybe I need to send you my sd cards...
2010-08-28 23:44 <xiangfu> wolfspraul: yes. I saw your email. then I fixed the last bug that I know.
2010-08-28 23:44 <xiangfu> wolfspraul: it's hard to output log to screen.
2010-08-28 23:45 <xiangfu> wolfspraul: send me the sd cards is better.
2010-08-28 23:45 <wpwrak> cut out the man in the middle :)
2010-08-28 23:46 <wolfspraul> ok
2010-08-28 23:47 <wolfspraul> does anybody want to adopt the qihardware twitter and identi.ca accounts? there is also a nanonote group on identi.ca
2010-08-28 23:47 <wolfspraul> all pretty badly neglected, so I want to clean up a bit
2010-08-28 23:47 <wolfspraul> if nobody wants to use them, I will just delete them
2010-08-28 23:49 <wolfspraul> there are maybe 150 or so followers on identi.ca, maybe 300 on twitter. still a while until it catches up with Lady Gaga :-)
2010-08-28 23:49 <wpwrak> maybe also kill the forum while you're at it ? ;-)
2010-08-28 23:49 <wolfspraul> I knew you would say that Werner :-)
2010-08-28 23:50 <wolfspraul> I think the forum is fixable, at least I will try myself.
2010-08-28 23:50 <wpwrak> that problem with these "fad" platforms is that the accounts there tend to get orphaned quickly. e.g., just look at all the placed on myspace that wikipedia still often links to. meanwhile, the people have long moved to facebook or such.
2010-08-28 23:50 <wpwrak> the forum would be great if it connected to the mailing list
2010-08-28 23:51 <wpwrak> but if it's just a parallel universe, it just creates diversion
2010-08-28 23:52 <wolfspraul> I have no problem with twitter and identi.ca it's just that I only have so much time, so I think either someone steps up and brings some life into those accounts, or we do everybody a better service by closing them.
2010-08-28 23:52 <wpwrak> it's of course easy enough to ignore if you already know that the mailing list is where things are really happening. but it can trap newcomers. also, people who just want to see what's going on in that strange project find a seemingly abandoned site. not good PR.
2010-08-28 23:54 <wpwrak> (twitter etc.) they need constant attention to be useful, yes. you could perhaps automate some tweets or so. but i'm not sure if it's worth the trouble.
2010-08-28 23:55 <wpwrak> (automate) e.g., tweet is a thread on the list exceeds a certain size/message frequency. or pick commits, maybe even randomly.
2010-08-28 23:56 <wpwrak> new project creation could also go there. or maybe after a few commits, so that people don't only see that something will (maybe) happen, but that they come visiting when there's some meat already.
2010-08-28 23:57 <wolfspraul> nice ideas. let's see whether someone wants to step up around these accounts, and if not they are deleted :-)
2010-08-28 23:58 <wpwrak> if you want to experiment with automated news, you could send them to a list created for that purpose. if the concept works, you could add interfaces list->twitter etc.