<wolfspraul>
the tech industry is quite self-referential sometimes
<wolfspraul>
but actually it's only a small part of life
<lunavorax_frizzl>
Hum
<wolfspraul>
so if the marketing departments of a few companies are working in overdrive, so what?
<lunavorax_frizzl>
Maybe you're right wolfspraul
<wolfspraul>
also I think journalism is going through a lot of changes
<lunavorax_frizzl>
What would it takes to reduce the production cost of the NanoNote down or close to the hypotetical price of the Raspbery Pi ?
<lunavorax_frizzl>
Journalism ?
<wolfspraul>
and we need it to come out well, 'we' not as tech poeple, but for society
<wolfspraul>
yes sure, journalism
<wolfspraul>
newspaper subscriptions falling like a rock
<wolfspraul>
so a lot of what you read is written by companies for marketing reasons
<wolfspraul>
don't take it too serious :-)
<wolfspraul>
meanwhile new forms of paying for independent journalism are growing slower than the old ones are disappearing - right now
<wolfspraul>
so naturally in a lot of places you actually look at advertisement now
<wolfspraul>
because you talk about 'smartphones/cloud computing'
<wolfspraul>
the media are full of it, because they copy/paste articles written by companies with vested interests in this
<lunavorax_frizzl>
Oh ok
<wolfspraul>
but no matter how much they repeat the same thing, I'm sure >90% of people don't give a damn, they just wait and see what actually works for them
<lunavorax_frizzl>
Hum that explains
<wolfspraul>
which is typically maybe 1% of what marketing claims, no? :-)
<wolfspraul>
well this is my thinking
<wolfspraul>
I'm all relaxed
<lunavorax_frizzl>
Haha
<wolfspraul>
I survived the Symbian dark age
<wolfspraul>
the Symbian dark age was a time where seemingly everybody agreed that Symbian = smartphone
<wolfspraul>
Symbian = great apps
<wolfspraul>
Symbian = great for developers
<wolfspraul>
only problem, it was all not true
<wolfspraul>
end users knew, because nobody used those smartphones for anything but phone calls, because...
<wolfspraul>
your guess :-)
<wolfspraul>
the other stuff didn't work :-)
<wolfspraul>
finally we made it through the Symbian dark age
<wolfspraul>
and who remembers all the wild claims they made back then, on good pay? nobody...
<wolfspraul>
because it doesn't matter
<lunavorax_frizzl>
Hehe indeed
<lunavorax_frizzl>
Why was it great for developers ?
<wolfspraul>
it wasn't
<lunavorax_frizzl>
Ah ok sorry
<wolfspraul>
but it's very hard when you go against the 'commonly accepted wisdom', at that time
<lunavorax_frizzl>
Propaganda from the past still fools me
<wolfspraul>
maybe that's how you feel right now about cloud, smartphone, etc.
<lunavorax_frizzl>
Hum yeah
<wolfspraul>
but you are just arguing with an imagined enemy
<wolfspraul>
maybe your own fears
<lunavorax_frizzl>
Is Android still equal to "code in Java or die" ?
<wolfspraul>
try to talk to someone on the street, they will agree with you about 'cloud computing' :-)
<lunavorax_frizzl>
Haha
<lunavorax_frizzl>
My cousin does but he's an ingeneer
<wolfspraul>
it's cool, no? computers in the clouds now? great!
<lunavorax_frizzl>
hahaha
<wolfspraul>
what do you do on a perfectly sunny day?
<wolfspraul>
no computing?
<wolfspraul>
makes sense! can enjoy the beach then!
<wolfspraul>
yeah, this is great stuff
<lunavorax_frizzl>
Hum
<wolfspraul>
yes I think in Android you need to code in Java
<lunavorax_frizzl>
Well maybe I just need to relax
<lunavorax_frizzl>
Oh damn :(
<lunavorax_frizzl>
I'll just focus on complaining about gnome 3 then :P
<lunavorax_frizzl>
Something funny I see on forums theses days
<lunavorax_frizzl>
Everybody is talking about forking Gnome 2 but nobody is doing it. I think I can understand why :P
<wolfspraul>
the Internet seems to becoming a cluster of talkers
<lunavorax_frizzl>
Also yeah
<wolfspraul>
I've noticed the quality of comments sections in online publications to go down dramatically in recent years
<lunavorax_frizzl>
But also Gnome 2 is a seriously heavy project, I don't need (and can't) to dive into such an amount of code.
<wolfspraul>
now you basically have a competition between extremist opinionists
<wolfspraul>
people who have nothing to do, and I guess draw satisfaction from this sports
<wolfspraul>
the only thing the reader can get from it is that sometimes those comments are so freaking extreme that you just have to laugh
<lunavorax_frizzl>
Hum
<lunavorax_frizzl>
Still you haven't aswered my question about the NanoNote wolfspraul :P
<wolfspraul>
ah sorry, one sec
<lunavorax_frizzl>
No problem
<wolfspraul>
hmm
<wolfspraul>
the raspberry pi is an announcement only now
<wolfspraul>
it's basically yet another proprietary breakout board
<wolfspraul>
if he can use the software stack from the chip maker 1:1, then his cost should stay under control
<wolfspraul>
it has no screen, no keyboard
<lunavorax_frizzl>
Software stack ?
<wolfspraul>
kernel mostly
<lunavorax_frizzl>
ok
<wolfspraul>
with the current ingredients, we cannot bring the nanonote to 25 USD
<lunavorax_frizzl>
25usb still is super good
<lunavorax_frizzl>
Hum
<lunavorax_frizzl>
usd sorry
<wolfspraul>
maybe 49 is possible, it would require higher volume which would require more orders which would require a much more valuable software experience
<wolfspraul>
let's say I make 10K units of 49USD nanos now, can I sell 10K units? I doubt it.
<lunavorax_frizzl>
I'm deeply thinking theses days about how the NanoNote can do what the Raspberry Pi can't. For now it only need a good doc for kids... still 100usd is too expensive for
<lunavorax_frizzl>
-for
<lunavorax_frizzl>
Even me, I'm not poor but I know my parents would have chocked if I told them the price of the NanoNote
<wolfspraul>
I think a cheap Android phone with touchscreen is not bad, no?
<wolfspraul>
production cost is about 30 USD, so they should exist in Europe for ca. 50 USD I would think
<wolfspraul>
underground China import channels of course
<lunavorax_frizzl>
I don't know, you already told me about that. I'm skeptical about the touchscreen, why not a keyboard like the Blackberry ?
<wolfspraul>
ah I said the same thing earlier, great
<wolfspraul>
I passed the consistency check :-)
<lunavorax_frizzl>
hehe
<wolfspraul>
I thin keyboards will go away
<wolfspraul>
over time
<lunavorax_frizzl>
I honeslty think that a ZX Spectrum look alike NanoNote (composite out, usb in) would definitely outburst the Raspberry.
<wolfspraul>
the reason I like it on the NanoNote is because it was what we could really pull off at the time, and make a lot of good free software (not Android) usable
<lunavorax_frizzl>
Oh how sad :(
<wolfspraul>
but in the long run, over years, I cannot see how it won't all move to capacitive touch or some other even better touch technology
<wolfspraul>
that's yet another big challenge for free software, we'll get to it
<lunavorax_frizzl>
how sad --> keyboard disapearing
<wolfspraul>
if you are typing away on a piece of glass, what's the difference?
<wolfspraul>
if I think about my experience with keyboards, I started training how to type with an old typewrite of my parents, before I had my first computer
<wolfspraul>
because I wanted to be able to type when the great day arrived and I got my first computer :-)
<wolfspraul>
those were big clunky keys!
<wolfspraul>
have to press down 2 cm or so, even more
<wolfspraul>
crazy
<wolfspraul>
then the first keyboards arrived, and they were also clunky
<wolfspraul>
then the keys got lighter and lighter
<wolfspraul>
the notebook keyboard I'm typing on now doesn't require much pressure at all. if it were a flat glass, ok I would have no tactile feedback. so?
<wolfspraul>
do I really need that or did I just become used to it over the years?
<wolfspraul>
if you try with a 5-year old now, would they miss the keys? or just happily type away on the glass?
<lunavorax_frizzl>
wolfspraul, you mean on all devices or only mobiles one ?
<lunavorax_frizzl>
Also, if childrens need to have a computer to learn about computing, the hardware need to stay the same as long as possible. Goal is to educate, not to make money and make a new machine every 6months. That's something incompatible (unfortunately) with a lot (all?) of companies.
<wolfspraul>
well wait
<wolfspraul>
capacitive touch is here to stay too
<wolfspraul>
you run some wires, build up a field
<mth>
I don't think you can do blind typing without tactile feedback
<wolfspraul>
have a little firmware running at a few megahertz measuring changes to the field, and computing where you pressed
<mth>
and non-blind typing will likely be slower than blind
<mth>
but over 90% of people probably can't type blind anyway
<lunavorax_frizzl>
hum interesting point from mth
<lunavorax_frizzl>
but
<lunavorax_frizzl>
afair I've seen works on virtual keyboard on touch screen made for blind typing
<lunavorax_frizzl>
with positionate and rotate the screen depending on where you type on the screen
<wolfspraul>
I like to try new things. If someone would give me a glass/touch keyboard as a replacement of my notebook keyboard, I would put it in right away and try for a few weeks
<lunavorax_frizzl>
But still is no tactile feedback yes
<wolfspraul>
but it's a bit too early for that I think
<lunavorax_frizzl>
Yeah I don't know, I may sounds old for saying so but I don't want to change that habits at least for me.
<wolfspraul>
I can imagine typing away on glass.
<lunavorax_frizzl>
I tried it on an iPad in a store, it's weird
<lunavorax_frizzl>
But maybe I would have no troubles after a few days ? I don't know really.
<wolfspraul>
we all don't know until we try :-)
<wolfspraul>
I would not want to go back to the types of keyboards I had in the 90's
<lunavorax_frizzl>
Yeah
<lunavorax_frizzl>
That must be Asperger or something but so far I hate changing my habbits :P
<wolfspraul>
do I want to go back there? no. compared to that my keyboard now is already 80% flatter, remove another 20% and I'm on a flat glass surface...
<lunavorax_frizzl>
Also Linux maybe need to get rid of X in order to be ready for multitouch ?
<wolfspraul>
did anybody talk to them or did they write this themselves?
<wolfspraul>
I'm surprised because at least I didn't do anything, and they must have picked this up from somewhere, maybe xiangfu's announcement mail on the list
<wolfspraul>
yes but where does it come from? they are subscribed to the list and saw xiangfu's mail and then wrote this themselves? that'd be pretty cool...
<kristianpaul>
233139-11:14 < dvdk> hey, the freshmeat release announcement triggered an article in linux-magazine.de :)
<kristianpaul>
233141-11:14 < dvdk> so this is what freshmeat is good for :)
<wolfspraul>
ok next time we have software updates, we need to make sure there is an announcement on freshmeat
<kristianpaul>
hey, i dint knewt it about sftp. thats good
<wolfspraul>
maybe we should make a milkymist-firmware project too on freshmeat
<wolfspraul>
and when there's an update, post an announcement there with a nice summary/changelog
<kristianpaul>
good idea
<wolfspraul>
the linux-magazin.de post brought about 750 visitors or so, that's nice as every visitor matters
<wolfspraul>
makes me want to go back to the qi-hardware.com homepage and bring it to a much higher level in cleanliness etc...
<wolfspraul>
I think it can be far more seductive and interesting still :-)
<xiangfu_>
Your project has been submitted for verification. This process typically takes less than 24 hours. (Milkymist on Freshmeat.net)
<xiangfu_>
:)
<wolfspraul>
xiangfu: nice!
<kristianpaul>
hum, i dont see the in ICD- GPS-200 the ionosphere word... may be they just call it diferent ;)
<kristianpaul>
argg, my fault, missing capital letter..
<wolfspraul>
how is the GPS data analysis going? I mean from the live data you capture, can you tell anything already?
<kristianpaul>
well, same, still on Pull-in state, so no tracking yet
<kristianpaul>
Pull-in is third state for channels in osgps
<kristianpaul>
now checking i have a good/proper setup of osgps, like update alamanac and utc, now checking ionosphere model parameters
<kristianpaul>
so no mor updates so far wolfspraul :-)
<wolfspraul>
I'm a glass half-full guy, so 'third state' sounds good
<wolfspraul>
:-)
<wolfspraul>
I guess first and second state already passed, so there is light at the end of the tunnel
<kristianpaul>
:-)
<wolfspraul>
or maybe first state is only "successful fopen()" and second state is "successfully read into ram"?
<wolfspraul>
better don't tell me...
<kristianpaul>
also i can ping Clifford Kelley (osgps developer), but i need be sure i have a good explanation of my issue, wich acording last conversation this format i'm using per byte (IIQQIIQQ)Â Â is keep i should not have problems
<kristianpaul>
no no, nothing about fopen and such
<wolfspraul>
of course I was joking about my states...
<kristianpaul>
no, is okay, actually i found in osgps code, some values were harcoded to fix another sige fronted sampling clock, so well, i need to keep in mind too just in case
<wpwrak>
DocScrutinizer: (energy harvesting) victor asked me whether it would be possible to strap an RF-equipped sensor (with very low duty cycle of course) on a power cord and i wanted to find out if there's really enough power there to do something useful with it.
<DocScrutinizer>
hmmm, interesting
<DocScrutinizer>
wpwrak: well, there are RF lightswitches to stick on the wall and power is from piezo when pressing the switch, so...
<wpwrak>
(piezo) oh, that's nice. didn'
<wpwrak>
t know of these
<wpwrak>
of course, all proprietary system/protocols, i guess ?
<DocScrutinizer>
sure
<DocScrutinizer>
\o/ my 10min experimental art shortmovie is almost uploaded
<DocScrutinizer>
took only like 6h
<wpwrak>
wow
<DocScrutinizer>
is waiting for "Sorry, file too large for OVI" ;-P
<wpwrak>
hollywood will hate you. a 1:36 movie to production ratio would mean that a 1.5 hours move should be done within 7 days :)
<DocScrutinizer>
244MB, it got to ~200MB when my DSL had reconnect and OVI-share upload started new instantly - smart sucker
<DocScrutinizer>
wpwrak: it's spontaneous art, a live act with N900 the main character :-)
<DocScrutinizer>
actually I think you'd have a hard time coding this if you planned
<DocScrutinizer>
even with soundtrack ;-D
<DocScrutinizer>
is wondering if he can find a purchase receipt for asking Logitech for a MX Revolution replacement
<DocScrutinizer>
damn critter should last longer than 3..4 years, at a price tag of almost 90EUR
<wpwrak>
phew. the cost of the logistics of filing all receipts for that long would probably exceed that value ;-)
<DocScrutinizer>
glares furiously at that OMRON D2C-F-7N horseshit, which is infamous for breaking after 1y avg
<DocScrutinizer>
not that the SMT switches used in MX Rev are any much better
<whitequark>
DocScrutinizer: what prevents you from replacing the switches yourself?
<DocScrutinizer>
the fact I did that last time like 6 months ago
<whitequark>
maybe you should get better replacement switches? :)
<DocScrutinizer>
(movie) no error msg, just got silently redirected to /dev/null :-(
<DocScrutinizer>
whitequark: indeed, but for the SMT ones the replacement sucks, and for the microswitches it's not really easy to find an exactly fitting better replacement
<wpwrak>
wolfspraul: (kbd) you could try a "flat keyboard" experience already with exiting technology. there are those laser keyboards that just use a table. e.g., this one (alas out of stock) http://www.thinkgeek.com/computing/keyboards-mice/8193/
<DocScrutinizer>
heard it sucks
<wpwrak>
me too
<wolfspraul>
and then you want me to try?
<wpwrak>
but wolfgang thinks keyboard without tactile feedback may be great
<wpwrak>
which are ironically some of the most sought-after by people who type a lot :)
<wolfspraul>
nah :-) I said none of those things
<DocScrutinizer>
the reason I don't want tablets nor phones w/o hw-kbd
<wolfspraul>
I said I don't want to go back to that one
<wolfspraul>
wpwrak: are you using one of those?
<wolfspraul>
yes, I like the easier to type notebook keyboard I have now better than those old ones
<wpwrak>
i use the HHKB, which is somethat similar. i know the ibm keyboards and i loved them.
<wolfspraul>
back then. but now we have something better :-)
<DocScrutinizer>
wow IBM kbd *with trackball* ???
<wolfspraul>
anyway everybody can choose whatever they like. I don't see a point of pressing hard being good.
<wolfspraul>
zero tactile feedback is another matter
<wolfspraul>
and I didn't say I like that, I said I would like to try
<wpwrak>
the layout of HHKB is a bit similar to that apple keyboard. even more compact, though. and more unix-ish
<wpwrak>
(like to try) that's why i mentioned it - you can already try it :)
<wolfspraul>
if it's bad there is no need to try
<wolfspraul>
I wait until you tell me there is one with zero tactile feedback that is good because you tried, and then I will try
<wolfspraul>
how about that?
<DocScrutinizer>
isn't a kbd with zero tactile fb exactly what you get on any tablet?
<wolfspraul>
I don't think they are ready for fast 10-finger typing, not sure
<wolfspraul>
I don't want my keyboard to slow me down, in fact I want my keyboard to make me speed up as much as posible
<DocScrutinizer>
nor will they ever be
<wolfspraul>
so I would choose the one where my typing speed is fastest, done
<wolfspraul>
:-)
<wpwrak>
on small devices you have to compromise :) and indeed, there's where is see most potential for non-feedback keyboard. below a certain size, you basically can't win.
<wpwrak>
but then, if you consider things like the OQO keyboard, you can go pretty small and it still feels good
<wolfspraul>
if a flat, no-feedback keyboard that supports full 10 finger typing comes out, and I can type faster on it than on my current notebook kbd, I'll switch
<wolfspraul>
that's basically my point
<wolfspraul>
and until that comes out, I continue on my notebook keyboard :-)
<DocScrutinizer>
anyway, printing and tinkering a paper kbd together is a nice weekend project : use tin foil and/or silver varnish to get the electrodes, and attach a simple sensitive matrix scanner
<wpwrak>
i think you need some form of feedback for fast typing. just seeing that you messed up on the screen probably isn't enough. besides, that means that you can basically type blindly
<wpwrak>
part of the feedback could perhaps be static. e.g. a shaped surface that lets you feel whether you're at the right position or not
<wpwrak>
of course, a shaped touch screen would be a hard sell ;-)
<DocScrutinizer>
hmm, you can inplement this to my paperkbd as well :-)
<wpwrak>
DocScrutinizer: looking forward to your paper keyboard movie then ;-)
<DocScrutinizer>
meh, I'm not interested in such a type of kbd
<DocScrutinizer>
(movie) the html upload page on OVI has a little note "not more than 100MB per file" :-/
<whitequark>
DocScrutinizer: I can offer you a spare server you can upload your movie to
<DocScrutinizer>
whitequark: thanks, got a server. just no "website" so it's not that attractive to try and watch a movie there. Pondering youtube... :-/
<DocScrutinizer>
never uploaded *anything* to YT
<DocScrutinizer>
nfc
<whitequark>
DocScrutinizer: I heard vimeo is much more friendly
<whitequark>
I've seen a lot of movies like that there
<DocScrutinizer>
plus then of course it's an accepted fact WW3 won't use nukes but viruses and trojans
<DocScrutinizer>
funny enough first threat (forgot the name... S.*?), to those Siemens SPS, been driven by Isreal/USA
<whitequark>
DocScrutinizer: Stuxnet
<DocScrutinizer>
yep
<whitequark>
that sounds even more funny in Russian, like "it will rot"
<whitequark>
wolfspraul: so there is another question you may know answer to. I always wanted to develop hardware, particularly digital stuff with microcontrollers (FPGA's too)
<qi-bot>
[commit] Ayla: Merge branch 'master' of projects.qi-hardware.com:gmenu2x into install_locations http://qi-hw.com/p/gmenu2x/ef4b012
<whitequark>
what is the best way to learn doing that?
<wolfspraul>
'digital stuff with microcontrollers', hmm
<wolfspraul>
you mean you want to design and manufacture a small embedded system?
<wolfspraul>
like Werner did with the ben-wpan boards?
<wolfspraul>
he is making 2-layer PCB at home, plus PCB antenna design
<wolfspraul>
or you mean purely the programmable fpga part, on an existing board?
<wolfspraul>
I don't understand how 'digital stuff with microcontrollers' and 'fpga' connect together...
<wolfspraul>
what kind of app/use case do you have in mind?
<whitequark>
wolfspraul: I don't think I can really do the full cycle for some piece of hardware, at least not now
<whitequark>
so I think I should begin with working for some company to gain experience
<whitequark>
but again, I must have something to show them so that they'll hire me
<wolfspraul>
what app/use case do you have in mind?
<wolfspraul>
what should the device be able to do in the end?
<whitequark>
I don't have any particular device in mind currently. (well, really I do, but any of the ideas I have won't be profitable on manufacturing; that's most one-time projects for myself)
<whitequark>
for example, I've been trying to do a home automation system for some time, which will connect most electrical devices (switches, lamps, sockets) in a wireless network and allow controlling everything in a centralized way
<whitequark>
but I clearly don't have enough RF experience to do that, as I understand now
<wolfspraul>
he
<wolfspraul>
but that does sound like ben-wpan a little, no?
<wolfspraul>
there is probably no other project like that with such extensive, actually massive, amount of documentation as ben-wpan
<whitequark>
sounds great
<whitequark>
maybe I should then begin with replicating ben-wpan
<wolfspraul>
you probably need to zoom-in/focus on something
<wolfspraul>
otherwise it may be overwhelming
<whitequark>
that's how it is
<wolfspraul>
maybe Werner has an idea for you
<wolfspraul>
something that is both good for ben-wpan, and will also help you achieve your educational goals
<whitequark>
huh, I doubt I can really make anything useful at the moment
<whitequark>
I'll talk with him anyway, through
<wolfspraul>
oh for sure you can do something useful!
<wolfspraul>
even if you try something, and fail, as long as you talk about what you do, exchange your experience with others, that can be very helpful for the project overall
<whitequark>
I'll then should get atusb/atben, to have a definitely working side
<whitequark>
does tuxbrain sell them already?
<wolfspraul>
not yet I think, last I heard was that SMT (the last production step) should be this week or next week
<whitequark>
okay, I'll then begin with ben
<kyak>
whitequark: if you decide about buying atben/atusb, i suggest that we consider group buying. Just need to think, maybe it's more reliable to buy it separately (the customs will more likely get suspicious with several PCBs, then just one or two)
<whitequark>
kyak: sure
<whitequark>
maybe we can also buy a pack of UBBs
<kyak>
i already did :)
<kyak>
have 5 of these thingies
<whitequark>
... or maybe not, even my skill is enough to make them manually
<kyak>
the price was so small, it's easier to buy UBB than to do it by hand
<whitequark>
link?
<dvdk>
group bying plans for atben/atusb: can i join? :)
<DocScrutinizer>
just an occasional "Duh! WTF! Mehehehe" from background - that's me
<DocScrutinizer>
camera like blair witch
<DocScrutinizer>
in ~3h it's upped
<Ayla>
whitequark: okay. So I believe I shouldn't make it default on gmenu2x then :)
<whitequark>
Ayla: if you're talking about SDL config, then it may still make sense
<Ayla>
I have a question for you guys.
<Ayla>
should we drop gp2x support on gmenu2x?
<Ayla>
the code is over-complex and messy, and one of the causes is that the gp2x support hasn't been totally removed
<Ayla>
some parts are commented, some are still here
<wolfspraul>
Ayla: wasn't there some activity in another gmenu2x somewhere?
<whitequark>
Ayla: I think yes, as that will make gmenu2x much more portable and usable on other devices
<Ayla>
either we remove all GP2X stuff, or we un-comment all the GP2X stuff and encapsulate it into #ifdef/#endif
<Ayla>
I *think* that the original author is still working on its own version
<whitequark>
(framebuffer) looking at linux/fb.h, there is no generic interface for double buffering, so it presumably should be done in SDL anyway then
<wpwrak>
(ben-wpan) i have no updates yet. they needed some clarifications on a file earlier this week, for the boards to "enter smt" this week. but nothing since.
<wpwrak>
(ben-wpan) i pinged them again some 5-6 hours ago ... (all the experience working with uncommunicative chinese comes rather handy in this case ;-)
<wpwrak>
whitequark: for learning to do things with microcontrollers, depends a bit on what you already know. you generally need a bit of understanding of general electronics, resistors, capacitors, diodes, transistors, nothing too fancy, just the basics, because you;ll run into them in one way or another all the time
<wpwrak>
whitequark: then there's a lot of architecture-specific knowledge about specific microcontrollers. larger embedded SoCs (the ben's ingenic, anything ARM and such) tend to have similar features but in a more orderly patters. the smaller you get the less orthgonal the peripherals become.
<whitequark>
wpwrak: well, I already know most of the basics. given that our XZ0032 board is comparable with Ben by complexity, I'd say that it is not a problem for me to understand a board of this level
<whitequark>
I've got a lot of experience with atmel uCs, some with 32-bit ARMs (simpler STM32 ones), and Ingenic mips
<wpwrak>
whitequark: okay, you're already quite far then ;-) your earlier experiments suggested as much :)
<whitequark>
but I'm still quite stupid when it comes to RF circuits and switch-mode power supplies (in the latter case, I was not able to implement even a single one which would have 80% efficiency :/)
<whitequark>
even when fully following instructions in datasheet
<wpwrak>
whitequark: rf is tricky. there's a lot of black magic there. i only started exploring that area myself not too long ago. basically with ben-wpan, some 9-10 months ago.
<wpwrak>
whitequark: (switchd mode) you mean for low (:battery") or high (mains) voltages ?
<whitequark>
wpwrak: I've built several variants of 3.6V->5V converter on different chips
<whitequark>
well, they worked somehow, but the efficiency was ranging from 10% (first ones) to maybe 50%
<whitequark>
and I have no idea why they were working so, or how should I have designed them the right way
<wpwrak>
that's surprisingly bad. were they just the usual 2-3 caps + inductor + chip type ?
<whitequark>
yeah, I've used ones with integrated FET and sensing resistor
<whitequark>
(I don't currently have schematics here on work, and so cannot say which ones exactly)
<wpwrak>
odd. external diode ?
<whitequark>
yeah
<whitequark>
Schottky
<wpwrak>
what kind of inductor ? small smt type, with some generous margin for the maximum current ?
<whitequark>
the one on board with highest efficiency I've used SMT one, through it was quite large, and rated a lot higher than the maximum possible current
<whitequark>
like 4 times
<whitequark>
well, it was the only one of the needed inductance I found in local store
<wpwrak>
that should be a healthy margin
<wpwrak>
maybe DocScrutinizer knows more about the pitfalls of such things
<DocScrutinizer>
hmm?
<wpwrak>
he's the resident electrical engineer. i just make things work ;-)
<DocScrutinizer>
can I get a sum up?
<wpwrak>
DocScrutinizer: whitequark made a switching mode up-converter but got poor efficiency (<= 50%). FET is in the chip. he used a schottky. inductor has 4x the max current rating. what else could be the problem ?
<DocScrutinizer>
parasitary capacitance
<DocScrutinizer>
inductor operating out of spec'd freq range
<DocScrutinizer>
also calculating "max I" for step converter inductors is a science
<DocScrutinizer>
that's NOT average current!
<DocScrutinizer>
if freq low, the inductor will saturate
<whitequark>
600k IIRC
<DocScrutinizer>
if high, you get loss in the ferromagnetics
<DocScrutinizer>
too high freq also makes parasitary C show up everywhere
<DocScrutinizer>
stepping converters are a bitch to pound to shape
<DocScrutinizer>
even app notes say: "test, change, test again" :-D
<whitequark>
oh, I found the part number: LM2700MT-ADJ
<wpwrak>
DocScrutinizer: and what if they say "ride whirl with summer wind plume" ? :)
<wpwrak>
(mount coil (inductor) with how air pencil) and yes, i just made this up ;-)
<whitequark>
and the inductor was enanAukdosh6orwy
<whitequark>
... not quite. more like CDRH103RNP-2R2NC-B
<DocScrutinizer>
you need to *very* carefully read and compare all the specs, diagrams, and recommendations. Even then sometimes it just "doesn't work" and you have to change some part. It's not unusual chip manuf's app notes mention a particular brand and build of inductor to use, as it turned out to be optimum
<DocScrutinizer>
some inductors also may have special PCB copper shape requirements (layout) so no phantom shortcircuit turns for the coil sneak in
<DocScrutinizer>
real fun
<whitequark>
DocScrutinizer: I don't have that board anymore, but I think I'll do a new one soon, as the topic is interesting
<whitequark>
DocScrutinizer: (pcb) not the case, my inductor was completely isolated and there was no copper under it except for pads
<DocScrutinizer>
even your case might matter, for same phantom turn reason
<vladkorotnev>
wolfspraul: can I have a folder in downloads.qi-hardware.com/people???
<DocScrutinizer>
but maybe around it, forming a "ring"?
<DocScrutinizer>
ground plane other side of PCB?
<DocScrutinizer>
it's tricky, I couldn't even spot the problem if I had the actual device in my hands
<whitequark>
hm, I've used single-sided PCB
<DocScrutinizer>
you know those electric nail guns to nail things on wood?
<DocScrutinizer>
I had one that refused to nail the isolation to my roof inside - turned out it was because there's been tin foil inside the whool mats
<whitequark>
I've only seen a mechanical staple gun, not sure if it is related
<DocScrutinizer>
electromagnetic staple gun
<lunavorax_frizzl>
Hum, the gumstix products are interesting
<whitequark>
DocScrutinizer: hmm, so it accelerates staples with a coil or something like that??
<DocScrutinizer>
had a coil the size of a huge camembert at the upper end, ~20cm from the nailing end where the tinfoil been. Still the tinfoil caused the electromagnet to fail
<DocScrutinizer>
the coil just pulls a hammer/bolt to neil the staple
<DocScrutinizer>
nail*
<wolfspraul>
vladkorotnev: sure, no problem
<wolfspraul>
let me check how the authentication works again :-)
<whitequark>
DocScrutinizer: that's weird
<DocScrutinizer>
just to show you coils care for their environment way farther than you'd think, sometimes
<wolfspraul>
vladkorotnev: do you want to upload with DAV or ssh?
<vladkorotnev>
wolfspraul: SSH better
<whitequark>
going to home now, bbl
<wolfspraul>
do you have a URL to your public key? or email it to me
<DocScrutinizer>
depending on build of your coil it may have more or less of mag field escaping the component
<DocScrutinizer>
btw the abstract art video is uploaded ;-)
<vladkorotnev>
wolfspraul: so?
<wolfspraul>
did you email your pubkey?
<wolfspraul>
checking...
<wolfspraul>
vladkorotnev: no email yet. I need your public key.
<wolfspraul>
you can give me a url if it's online somewhere, otherwise email
<vladkorotnev>
wolfspraul: how do I get my pubkey? especially if I have 3 PCs? :)
<wolfspraul>
check in .ssh/id_dsa.pub
<wolfspraul>
you can arrange your keys in any way you like, you can use the same private/public key pair on multiple computers, or you can have multiple keypairs on one computer and use them for different purposes
<wolfspraul>
but if you want to upload files, I need some public key from you, then you authenticate yourself with the posession of the matching private key
<wolfspraul>
if you don't have a keypair yet, you can create one with ssh-keygen
<vladkorotnev>
wolfspraul: cat: .ssh/id_dsa.pub: No such file or directory
<wolfspraul>
run ssh-keygen :-)
<vladkorotnev>
wolfspraul: it made id_rsa.pub :P
<wolfspraul>
now email it to me
<wolfspraul>
don't ever email or publish the id_rsa anywhere, that's your private key
<wolfspraul>
only the .pub
<vladkorotnev>
wolfspraul: ok, what email?
<wolfspraul>
you have a lot from me in your inbox, no? wolfgang@sharism.cc