#qi-hardware IRC log for Monday, 2012-03-26

wpwrakAyla: besides, unless you're really using 5.25" floppies and such, that choice isn't available anyway00:00
whitequarksigh00:00
whitequarkjust grab one of 1000s FAT access sample codes and declare it a day00:00
mththe standard sizes only works for floppies indeed, SD is a fake harddisk, which uses a single media ID code regardless of geometry00:01
wpwrakAyla: you'd still need to read the boot sector to determine the FAT entry size. and maybe also the beginning of the data. not entirely sure about the latter00:01
mthafaik you get FAT location and root dir location from the boot sector and data location from the FAT00:02
wpwrakmth: pioneers of mobile computing :-)00:02
Aylawpwrak: but why should I care about the entry size?00:02
AylaI don't get it00:02
wpwrakAyla: the FAT entries can be 12, 16, or 32 bits00:02
Aylaah00:02
wpwrakAyla: so unless your file is just one cluster short, you need to know the FAT entry size00:02
AylaI do check it00:03
AylaI simply exit the loading function when it's not FAT3200:03
wpwrakmth: i meant the position of the data sector corresponding to FAT entry 0 (cluster 0). i think it's at a non-zero offset.00:03
mthhmm, my knowledge is a bit rusty I'm afraid00:05
Aylahere's (part of) my code: http://pastebin.com/ZEJYJ74B00:06
mthI used to do all kinds of nasty editing in the file system, like making a subdirectory point to its parent and watch PC-Tools crash when reading the disk00:06
wpwraksbi->data_start = sbi->dir_start + rootdir_sectors;00:07
wpwrakand00:07
wpwraksbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length;00:07
wpwraklinux kernel, fs/fat/inode.c:fat_fill_super00:08
mthAyla: you might need some attribute to tell the compiler not to pad the struct00:08
wpwrakstill there after all these years :)00:08
Aylamth, I did check that, only the last one is padded00:08
DocScrutinizermth: haha, on early linux you could create that with standard tools00:08
Aylathe "fsdata" structure00:08
Aylabut it's like that on the original code too, so I'm not sure if I should alter that00:09
whitequarkAyla: note that some programs, e.g. mkfs.vfat, sometimes create FAT16 and FAT12 volumes depending on the size of media00:09
Aylathe structures are from u-boot btw00:09
whitequarke.g. if you will point mkfs.vfat to something 1.44MB in size, then chances it'll format it as FAT1200:09
whitequarkthere's an option for forcing the type00:09
Aylawhitequark: I'm not planning to put a floppy on my dingoo ;)00:10
DocScrutinizeralso there's an option to deal with inode size which changed from 128 to 256 eventually in mkfs and uBoot barfed up on that00:10
whitequarkAyla: there's the problem00:11
whitequarkif you will format a 2MB NAND partition with mkfs.vfat, it can _too_ format it as FAT1200:11
whitequarkso look out for that00:11
Aylaheh, come on00:11
whitequark(through using FAT on NAND partitions is an exceptionally bad idea anyway)00:11
AylaI'm writing code to boot from SD only00:11
whitequarkok, on a 2MB SD partition ;)00:12
whitequarkor it can be 10MB and FAT1600:12
whitequarkstill a potential for a failure00:12
DocScrutinizeroops, of course the inode size wasn't for FAT00:12
Aylawhitequark: the main root file system won't even fit on that00:12
DocScrutinizer:-D00:12
mthup to 32MB can still be FAT1200:12
mthFAT16 goes quite a bit further and could actually exists on SD00:13
AylaI don't want to support something we're sure we'll never see00:13
Aylathe code is not meant to go inside an OS, but is specific to the dingoo00:13
whitequarkmth: I don't remember exact details of FAT implementations. but I've been bitten by that quirk and so I'm saying00:13
DocScrutinizerdang, I never tested if FR uboot actually would boot from an ext2/3 with 128bit inode size00:14
DocScrutinizerI just seem to remember it been supposed to bot from ext in early days of gta0100:14
mthin any case, let's first get it booting from FAT32 and later add FAT12/16 support if we might need it00:14
whitequarkmth: Ayla: dump everything except FAT32. make a note in README.00:15
whitequarkfat16 support isn't worth the time required for it00:15
DocScrutinizeryup00:15
whitequarksupport for users not caring to read README isn't, too00:15
DocScrutinizeresp if those users dare to repartition a SD that by default comes with VFAT00:18
mthAyla: if you put filename and ext in one array, you can compare it to "VMLINUZ\0BIN" in one go00:21
Aylamth: probably, I'm not there yet00:21
whitequarkAyla: seriously, why not take an existing FAT access code?00:22
whitequarkit has been written way more times than it should be00:22
Aylawhitequark: I do have an existing FAT access code00:23
whitequarkso what's wrong with it?00:23
AylaI'm almost copying the u-boot code00:23
Aylabut there's so much stuff in there I don't need00:23
Aylaand I like to understand what I program00:24
whitequarkyet another wheel reinvented out of pure curiosity00:25
Action: whitequark has a collection of those00:25
Aylathat's called evolution00:26
Aylawheels used to be in wood00:26
Aylait has still the same function; but now each wheel is made accordingly to the system it composes00:27
Aylaa wheel from a bike is not the one from a car00:27
whitequarkI'll just go and look at rabbits. Funny little rabbits with black twitching noses.00:27
mirkokyak: are you trying to compile in directfb support?01:47
mirkobuilding qt4 frequently and don't experience this issue01:47
wolfspraulmirko: hey nice to see you!01:55
wolfsprauland thanks a lot for continued care about those things, I am still super happy about OpenWrt in general :-)01:56
wolfspraulif we can do things better for smoother integration, never hesitate to post it so we can learn01:57
mirkowill do, but have to figure out the actual problem before :)01:57
mirkowolfspraul: currently in greece, attending the wireless battle mesh meeting01:58
wolfspraulsure that was not in reference to this particular issue, just in general01:58
wolfspraulgreece, nice01:58
wolfspraulwireles battle mesh? wow01:58
wolfspraulI recently bought some of these little thingies, and of course OpenWrt on them - really good! http://wiki.openwrt.org/toh/tp-link/tl-wr703n01:59
mirkohehe, yeah bought some as well01:59
wolfspraul16 USD, 0.5W. finally a worthy successor of my aging nslu201:59
mirkovery neat devices01:59
mirkothey're not available in europe yet01:59
wolfsprauland openwrt really shines on them01:59
mirkohad to import them from HK01:59
wolfspraulwell. the reason is that EU+US markets are 'too small' :-)01:59
wolfspraulI just lump them both together02:00
wolfsprauland not price sensitive enough, that is a product that is so cheap is not pulled forcefully enouhg because none of the distributors are interested to work for such tiny margins02:00
wolfspraulbut they take off in the world's largest computer markets, starting with China, and then other huge and growing markets02:00
wolfspraulthey are everywhere here in China, at every corner shop02:01
mirkowolfspraul: there is also a different model - having a grey case instead of blue02:01
wolfspraulincluding low-cost variants (yes), like the 702n and even more lost-cost 'no-name' versions02:01
mirkoand kind of a display02:01
wolfspraullow-cost meaning another 1 USD less...02:01
mirkothe 702 has 2MB flash02:02
wolfspraulthere are many variants02:02
wolfspraulit's hard to imagine that there is another 'no-name low-cost' white label essentially02:02
wolfspraulfor a product that already retails at 16 USD02:02
wolfspraulbut there is :-)02:02
mirko:)02:02
wolfspraulyou can only understand this from the perspective of a huge market like china with 1.3 billion people, which is also extremely price sensitive02:02
mirkojust for the record: http://battlemesh.org/BattleMeshV502:02
wolfspraulthey will get to EU/US later, if anyone there cares...02:03
wolfspraul(it's the distributors that don't care, not the consumers, since it doesn't even reach them)02:03
wolfspraulbattle mesh, yes, reading02:04
wolfspraulvery interested in anything rf, mesh, p2p02:04
wolfspraulsdr02:04
kristianpaul702, not be supported in OpenWRT !! oh02:05
wolfspraulyeah come on, stay away from those 'cost-down' versions02:05
wolfspraullike removing the USB connector to save, what, 10 cents?02:05
wolfsprauland then not having USB host because of that...02:05
mirkokristianpaul: 2MB flash - you can strip openwrt down to fit in 2MB but it's just not worth it and fun02:06
kristianpaulmirko: and poor usefullness  later..02:06
wolfspraulmirko: so you are a 'mesh networking enthusiast and community networking activist'? cool! :-)02:07
kristianpaulbattle rf could be fun ;)02:09
mirkowolfspraul: well, it's all OpenWrt related as well02:10
mirkosince most nodes are running OpenWrt02:10
kristianpaulremoving the USB connector, remenbers me some of nanonote history about usb host :)02:11
wolfspraulmirko: I think OpenWrt is doing just fine02:11
mirkoyeah, got most OpenWrt-devs to attend the event as well02:11
wolfspraulso I am serious when I worry about 'how can we integrate with upstream (owrt) better', 'how can we keep long-term maintenance costs down', etc.02:11
wolfspraulthe future is bright :-)02:12
mirkoyesterday we had quite a long and productive meeting dedicated to openwrt02:12
kristianpaulmirko: havent seems rtl-sdr?02:12
kristianpaulsee*02:12
wolfspraulah hey, we need really good milkymist soc support in openwrt one day :-)02:12
wolfspraulbut some homework to do on our end first, ahem. say a year or so :-)02:12
mirkowolfspraul: well, i'm willing to assist but working full-time currently - bdesides my very own projects :)02:13
mirkohehe02:13
wolfspraulsure sure02:13
wolfspraulfirst priority is to keep ben nanonote image from falling apart02:13
wolfspraulon the milkymist side a lot of groundwork is missing and slowly being created02:13
wolfspraulmirko: from router manufacturers, which do you think are the most openwrt-friendly, or the best supported by openwrt?02:14
wolfspraulwhy do you need to bring ethernet cables, switches and hubs to a meeting that is all about wireless & mesh? :-)02:16
wolfspraulhttp://battlemesh.org/BattleMeshV5#What_to_bring02:17
mirkoin first instance it's drinking, partying, having no sleep and talking and hacking ;)02:28
mirkowolfspraul: it's hard to tell which manufacturer is best currently.. - there's one great netgear router which however costs about 90 euros02:33
mirkosuprisingly tp-link routers are usually getting supported quite fast as well02:33
wolfspraulyes, I didn't mean more or less 'random' products that were found to be 'good' in a reverse way02:33
mirkothey even advertise currently with openwrt compatibility02:33
wolfspraulbut I mean whether there are any manufacturers that have an active/proactive role wrt openwrt02:33
wolfspraulah yes, that's interesting! [ads]02:34
mirkotheir role in getting patches upstream is non-existent still02:34
wolfspraulare the firmware on those routers built with openwrt?02:34
mirkodepends on the models02:34
wolfspraulis there a manufacturer that realizes there is this thing openwrt and they should have a strategy to align their business with what is happening in openwrt?02:35
wolfspraulor not?02:35
mirkobut the number of manufacturers using a firmware by default based on openwrt is inrceasing02:35
mirkowolfspraul: not that we know of currently02:35
wolfspraulyeah I would think so02:35
wolfspraulin my opinion thinks like the little 16 USD router is what is leading/most innovative economically02:35
mirkowolfspraul: usually they just do it without notifying us - and usually their env is heaviliy patched and not based on some recent version of openwrt02:35
wolfsprauland those economics are tough02:36
wolfspraulat those pricepoints even the smallest engineering effort becomes a large percentage of their margin02:36
wolfspraulwhich should make them more interested in a smooth strategy that includes upstream02:36
pabs3mirko: are there any at all who commit their stuff upstream?02:36
wolfspraulbut I hear you. thanks! just double-checking...02:37
wolfspraulall the same old story then :-)02:37
wolfspraulfirst we wait until the router costs 2 USD, then we see what we do :-)02:37
mirkopabs3: not really - not as in: they provide useful patches ;)02:37
mirkowolfspraul: got it - thanks :)02:37
wolfspraulthey cannot afford the staff that would be able to do this02:37
wolfspraul'cannot' not as in cash liquidity, but as in being compatible with their business model02:38
wolfspraulmaybe some will slowly become just like a regular openwrt user. look up their hardware in the 'toh', then flash the image recommended there :-)02:39
wolfspraulthat would create an interesting chicken & egg problem :-)02:39
wolfspraulmirko: ah, one last thing. do you have any thoughts on qualcomm acquiring atheros?02:40
mirkowolfspraul: i'm not that much into this wifi thing.. can't tell02:41
wolfspraulI'm asking because it seems there are 2 major makers of the SoCs inside a lot of routers: broadcom and atheros02:41
wolfsprauland atheros was acquired by qualcomm over a year ago, so I would think that tech is being integrated into future SoCs02:42
wolfspraulbut I know too little there, just watching over time and trying to figure out where the interesting new things are happening02:42
wolfspraullook at a product like the tp-link TL-MR11U, a battery powered version of the 703n02:43
wolfspraulif it has gsm/lte built in? could be used for all sorts of things02:43
mirkoi know that atheros is restructering in way which goes away from the opensource efforts02:50
mirkopeople are trying to hard to avoid this and try to convince them not giving up this path02:50
wolfspraulqualcomm has money to finance proprietary innovation, in fact the profitability of such investments in the past has made them what they are today02:52
wolfspraulI think you will have a hard time convincing them about anything open. they will only open the parts that have lost profitability for them.02:53
wolfspraulthat's the theory02:53
wolfspraulbut in reality the open routers we have today are cool, no? I only think about the value of the open part...02:53
mirkolantiq is great02:55
mirkothey not producing routers but soc's and eval-boards02:56
mirkothey are really openwrt-friendly02:56
wolfspraulah interesting. thanks! I will definitely check that out.02:56
mirkoand finance people writing opensource drivers for them02:56
wolfspraulthat's what I meant :-)02:56
mirkothey're one of the few provising an abstracted API for voip/dsl support02:57
mirkousually we just get *.ko-files02:57
wolfspraulI will read about them some more, very helpful thanks a lot!02:57
mirkothey encapsulated it into a firmware blob but the API from the kernel and userspace is kept the sam02:57
mirko*same02:57
wolfspraulI'm trying to understand the companies and their business models, not just looking at products one by one.02:57
mirkowelcome02:57
mirkoneed to get some sleep now :)02:58
mirkosee ya02:58
cladamwwolfspraul, please add me as happy member under http://projects.qi-hardware.com/index.php/p/kicad-libs/ Thanks a lot !08:43
wolfspraulcladamw: added08:46
wolfspraulexcellent let's take that on!08:46
cladamwnice !08:47
qi-bot[commit] Xiangfu: cgminer: increase the MAX_DEVICE to 64 (master) http://qi-hw.com/p/openwrt-packages/b96e10c09:49
qi-bot[commit] Xiangfu: Merge branch 'master' of projects.qi-hardware.com:openwrt-packages (master) http://qi-hw.com/p/openwrt-packages/617627f09:49
qi-bot[commit] Xiangfu: Merge branch 'master' of projects.qi-hardware.com:openwrt-packages (master) http://qi-hw.com/p/openwrt-packages/9a1536109:49
qi-bot[commit] Adam Wang: Added WM9707SCFT/V symbol (master) http://qi-hw.com/p/kicad-libs/b4543b910:04
cladamwwpwrak, nice today I treated myself ! :-)10:30
wpwrakvery good ! :)10:30
cladamwwpwrak, http://projects.qi-hardware.com/index.php/p/kicad-libs/source/commit/b4543b9/10:30
cladamwyes, ours version are different surely. One question:10:30
wpwraki'm looking at it right now ...10:31
wpwrakperhaps it's time to switch to using  git add the_file(s)_you_really_want_to_commit10:32
wpwrakand only then  git commit10:32
cladamwwpwrak, http://dpaste.com/721470/10:32
wpwrakthat way, you can leave out all the "noise" kicad produces. e.g., your commit also changed things you didn't modify, for example because of the (stupid) timestamps10:33
wpwrak(dpaste) yes, that far it was good. what went wrong after ?10:33
cladamwmy question is why components.pro still has been committed ?10:34
cladamwit seems that I didn't use  git add components.pro  though10:34
wpwrakit's the  commit -a10:36
wpwraksince you already did    git add ...10:36
wpwrakyou would have needed only  git commit10:36
wpwrakgit commit -a commits everything that has been added plus everything that already existed and that has changed10:37
cladamwso next time I don't need use '-a' just use  git commit   10:37
wpwrakthat's why you also commited "changes" to c8051f320.*10:37
cladamwis that right ?10:37
wpwrakyes10:37
cladamwyeah...phew~10:37
cladamwsorry that. that's why i felt wrong that why c8051f320.* still be modified. :(10:38
wpwrakbtw, there is a useful script in wernermisc/bin/purge10:38
wpwrakit removes timestamp changes from .pro files :)10:38
cladamwphew~ so next time: I have to just use  git add <FILE>  and git commit, right ?10:38
wpwrakthat is, if only the timestamp has changed, then it removes it. if anything else has changed, it leaves the change(s) there10:39
cladamwwow~ so could you change c8051f320.* back to previous ones ?10:39
wpwrakafter the commit, you should check if there are no other changes you want to commit. (git status or, better, git diff and git diff --cached)10:39
wpwrakif there's nothing else, you can throw away unwanted changes with  git stash10:40
wpwrak"git stash" means that the changes are still around, so if you made a mistake, you can still recover them. but they're out of your way.10:41
cladamwphew~ those are may hard a bit for me to understand now.10:42
wpwrakgit is all about the workflow ;-)10:42
cladamwbtw, when you use components.pro to add/modify symbols, will you always commit it ? or no need, since i think the components.pro is just for local laptop purpose. right ?10:44
cladamwi'll not commit it even I create new symbols. is it make sense to you ?10:45
wpwraki commit it, because that way, anyone can access the new component with eeschema10:45
wpwrakotherwise, they'd have to add it manually10:45
wpwrak(access it) from kicad-libs/components/10:45
cladamwhmm...okay. i see now.10:45
wpwrakyou can   make sch  there10:45
wpwrakand then invoke the component viewer10:46
cladamwaha...nice that   make sch  there.10:47
qi-bot[commit] Werner Almesberger: a bit of meta-data cleanup after the wm9707scft commit (master) http://qi-hw.com/p/kicad-libs/6faf61110:49
cladamwwpwrak, well... so i'll keep to add symbols for m1r4 these days once i'm available... phew~ soon, we'll have KiCad m1r4 sch. ;-)10:49
wpwrakyou forgot to add yourself as author :)10:49
wpwrakpin 46 is an input ?10:50
wpwrakpin 12, too ?10:51
cladamwwpwrak, how can i edit "./wm9707scft" in the "Preference >> Library" ?10:52
wpwrak(don't forget to  git pull   after my commit, before making any new changes. else, you'll have a merge conflict, e.g., on *.pro)10:52
wpwrak(edit) you mean you want to rename it ?10:53
cladamwsince I found that i tried to add "./" for it. yeah.10:53
cladamwbut don't know how to use it10:53
wpwraki added the  ./10:54
cladamwso you edited the file directly not by EESchema ?10:54
wpwraki just edited the .pro file with a text editor :)10:54
cladamwoah.... got it. man 10:54
wpwrakyes, of course. it's much quicker that way ;-)10:54
wpwrakalso, kicad may try to change ./ back to nothing10:55
cladamwalright, i still have a lot of "git" to learn10:55
cladamwyeah...pin 46 is NC, no need an input, 10:55
wpwrakbtw, do you know this one ? http://people.openmoko.org/werner/gta02-core/gta02-core-expanded-all.pdf10:55
wpwrakthat's still from gta02-core. an view of components with their pin types10:55
wpwraki guess it'll be useful to add something like this to kicad-libs now, too10:56
cladamwyeah...so you want me to add symbols as gta02 as possible for m1r4 ?10:57
wpwraknot yet. let me set up the framework for it first ...10:58
cladamwhmm...yeah10:58
cladamwi think we need to set catagory for components, like different lib for like varistor, connector, etc. ? or after your framework. ;-)11:01
wpwrakyes. just populating Logic - Single :)11:04
wpwraklet's try two levels of category, and then 1, 2, 3... for now11:04
cladamwwpwrak, how to use  git stash  after my http://dpaste.com/721489/11:10
wpwrakare there any changes you want to keep ?  (git diff / git diff --cached   ?)11:10
cladamwwpwrak, i don't want to commit *.pro. so just  git checkout -- *.pro ?11:11
wpwraknot sure if this works. try it :)11:12
cladamwnice, just  git pull origin master  and pulled your new commit. thanks ! phew~ fires on git for me.11:15
wpwrakhmm, this calls for a new script ...11:48
wpwrakand adam will need scriptable kicad soon :) wolfspraul, the procrastination will be short-lived :)11:58
wolfspraulwpwrak: oh I'm glad if we can step up, me included12:32
wolfspraulwhich procrastination?12:32
wolfsprauldid you see the recent kicad-scripting patch on the kicad list?12:32
wolfsprauleverybody seems to like that, and it will force the same way of code cleanup that will help cmdline processing12:33
wolfspraulI was thinking more specifically about kicad layout today12:40
wolfspraulso kicad has no autorouter, or semi-auto router12:41
wolfspraulbut how bad is the manual one?12:41
wolfspraulhow efficient or inefficient?12:41
kyakmirko: yes, i'm building qt4 for directfb support (as by default for nanonote)12:41
wolfspraulcan you annotate layout or save layout rules together with the traces?12:41
wolfspraulhow reusable is a kicad layout if someone wants to make an improved or different board?12:42
wolfspraulI was looking at a new Intel board I got (DN2800MT) and I was admiring the traces I saw even on top & bottom. could be a lot of layers too. pretty much all traces seemed to be following a number of rules, lots of pairs, lots of length-matching or other irregular shapes like serpentines, weird angles, etc.12:43
wolfspraulso I was wondering how good the 'auto-router' even in the best EDA tools might be12:44
wolfspraulmaybe in the end you will always need to do a lot of manual intervention on anything high-performance?12:44
wolfspraulthat Intel board certainly looked like that...12:44
jonandthe autorouters of today are decent, but it's not trivial to set them up to do what you want to achieve12:44
kyakmirko: it's a pity it's working fine for you :) so i guess i'll just wait till it hits buildhost (i guess it already did - all qt4 packages magically failed to build in the last "release"). For now buildhost is stuck building some xfce stuff, which needs to be disabled at all (xiangfu?)12:44
wolfsprauljonand: do you know anything about how good/bad/usable/reusable kicad layout is?12:45
jonandI don't, I heard about kicad only a few weeks ago when I listened to theamphour podcast in my car. I use Cadence tools at work and I've done a few hobby projects in Eagle a few years ago, but I've never tried Kicad.12:47
wolfspraulkicad and geda seem to be the two most advanced free schematics and layout suites (geda is a collection that includes some other tools as well I believe)12:48
wolfspraulwhat is "theamphour podcast"? checking...12:48
kyakmirko: another thing: qt4 lacks librt as a dependency. How to reproduce: build a minimal image with qt4 only and some app. When launching the app, it complains for missing librt.so.12:49
wpwrak(scripting patch) lemme check ...12:49
jonandI'm not a layout professional, but the rumors are that the Mentor tools are a step up from Cadence. Here is an article on driving the autorouter on a 400 diff pair 16 layer board. http://www.techdesignforums.com/pcb/pcb-topics/constraint-driven-design/learning-the-value-of-preparation-and-simulation-by-osmosis/12:52
kyakmirko: and the lastest thing: dejavu-fonts-ttf package been split into many packages (i think you did that). However, choosing the "dejavu-fonts-ttf" in menuconfig (or automatically via dependencies) doesn't select subpackages. Therefore, the package "dejavu-fonts-ttf" itself is an empty package and now i don't know how to make an application build with basic font support (unless i choose to depend on a specific font from dejavu-fonts-ttf-*)12:53
kyak(sorry guys for interrupting... )12:53
wolfsprauljonand: excellent link, thanks a lot. I will *definitely* read this.12:53
wolfspraulone thing I noticed over the years that as much as people talk about how much they prefer this or that tool, or this or that feature in a tools, or how much superior this or that tool or company is, in reality that mostly speaks for the experience of the speaker more than for the tool12:54
wolfspraulin other words - the tools can pretty much all 'achieve' the same results, but over often many years, users of tools get totally intertwined with one particular tool or approach, and then find many reasons to explain why that is so12:55
wpwrak(scripting) sounds promising. let's hope it's not overly tied to having a window.12:55
wolfspraulI wouldn't look at anything past kicad or geda these days.12:56
wolfspraul(for those 2 pieces - schematic capture and layout)12:57
wpwrak(router) the manual routing is pretty decent. when drawing a trace, it helps you find where to go: DRC will only make points on the same net accessible, "magnetic" pads will draw the trace to the center of the pad, "magnetic traces" will give you drop points off-grid at intersections, and traces can "hug" each other (caution: using this feature, you may have to rip up a number of traces if you want to change anything, since they'll be12:59
wpwrak tightly packed)12:59
wolfspraulif werner had to layout such a board, he would write a small parametric tool just for that board :-)13:00
wolfspraul(talking about jonand's link, excellent read imho)13:00
wpwrakthe parts that are not so good are: traces can't push other traces out of the way (that would be semi-atomatic routing or a "push router"). also, undoing and redoing things needs a lot of clicks13:00
wolfsprauland again if you look at 'lessons learned', they didn't use HDI because nobody had experience and they felt they didn't have the time to learn about that13:01
wolfsprauland had they known their tool better (I/O Designer), they would have used it differently from the beginning :-)13:01
wpwrak(board example) it does look quite parametric, doesn't it ? ;-))13:01
wolfspraulyes, absolutely13:02
wolfspraulI think that would be the right approach to layout such a board13:02
wolfspraulactually that's what they are doing, just with tools they don't really know that much about (but learn as they try to throw the first problem at the tool)13:02
jonandwhen I started to work as an electronics designer I soon found out that designing anything that is more advanced than microcontrollers with everything built in requires some knowledge in how boards are built up and why. 13:03
wpwrak(kicad routing) what's important is that i never ran into a situation where i felt kicad was abandoning me. you can always solve the problems, even if it's sometimes a bit circuitous13:03
wolfsprauljonand: absolutely13:03
jonandthere are some excellent books on the subject, like Howard Johnson "high speed design - a handbook of black magic", written in the 90s13:03
wolfspraulwpwrak: kicad would probably be terribly bad fit for a board like in jonand's text13:03
jonandstill very valid today - physics don't change... :)13:03
wpwrakyeah. everything manual13:04
wolfspraulbut then I believe for such a board you might really be best off to write a small meta-tool on top of a simpler base like kicad13:04
wpwraki mean, it does have autoroute and autoplace. but both are rather cruel jokes13:04
jonandthat said, I'd really advice anyone designing anything with say an FPGA plus external DDR or a CPU with memory to do some IBIS simulations13:04
wpwraklast time i checked, you couldn't even stop the autoplace. it tightly packs the components right next to each other, without regard for routing, and at glacially slow speed.13:05
jonandrunning SI simulations really make you understand a lot more about how layer buildup, (lack of) ground return paths, and vias will destroy your signals13:05
wolfsprauldo you have recommendations which free software to use for IBIS simulations?13:06
jonandI doubt there are any13:06
wpwrakhmm, we don't have such things for kicad yet13:06
wpwraksomething that may be useful to add at some point in time would be a trace length comparison: tell pcbnew which traces should be length-matched, then let it show differences, if any are encountered.13:07
wolfspraulok, one by one. First, you probably meant this book http://www.amazon.com/High-Speed-Digital-Design-Handbook/dp/0133957241/13:07
jonandthe most popular commercial ones are mentor hyperlynx and cadence sigxplorer13:07
wpwrakthis would still be a manual aid, but i think it could help a lot13:07
wolfspraulwe tend to blissfully ignore legacy software :-)13:08
jonandthat's the book, yes13:08
wolfspraul(I am joking, no worries, but it's just so much more fun if you can take the tools apart and it's all free and open... don't understand why any serious engineer can accept to work with blackbox tools, oh well :-))13:08
wpwrak(i firmly believe in automating the things that computers are good at while leaving the things that humans are good at to humans. so, in this example, let kicad do the boring trace length calculation, and let the human figure out what to do with that information)13:08
wolfsprauljonand: ok, thanks a lot for that link then, it may come in handy later13:09
wolfspraulnow IBIS, let me see whether there is anything in FEL, just as a quick search13:09
jonandhttp://www.eda.org/ibis/home/faq/#_1 <-- The parser is freely available in object code format <-- Stallman would explode if he read that line.. :)13:10
wpwrakjonand: he must already have grown a meter of steel skin at that spot :)13:11
wolfspraulwait wait, let's see. and btw, the Milkymist One board has a spartan-6 fpga and ddr1 memory, and it's working nice and stable13:11
wolfspraulI'm not dismissing ibis, not at all, just happy that we got it this far already.13:11
wolfsprauloh well, no mention of IBIS at all in http://chitlesh.fedorapeople.org/FEL/list.html13:12
wolfspraulso another thing to look at later :-)13:13
wpwrak(kicad routing) you can save certain design rules: you can categorize nets and assign a track width, clearance, and via parameters to them. all a but crude, though.13:13
jonandhow is milkymist related to qi-hardware?13:15
wolfspraulthanks for asking13:15
wolfspraulMilkymist SoC first is an SoC project13:15
wpwrak(cure) e.g., if you have a high-current trace and the trace for a level probe going to it, then both would be the same net and you therefor would have the same trace width for the probe. that is, without switching off DRC or inventing a magic component that splits the trace13:15
wpwraks/cure/crude13:15
wolfsprauluses the open LM32 core from lattice (about 25% of the codebase), and then a lot of gpl-licensed peripherals around that13:15
wolfspraulthen there's a lot of stuff on top of the SoC to actually make it work in a practical environment13:16
wolfspraulnamely a BIOS, rtems kernel, flickernoise app13:16
wolfspraulall of this then comes out as the Milkymist One video synthesizer13:16
jonandI met sebastien at HAR2009 where he presented the milkymist, but I'm not up-to-date with what happened with the platform since then. 13:16
wolfspraula hardware product you can buy for 500 USD13:16
wolfsprauloh nice13:17
wolfsprauljust checkout milkymist.org or https://sharism.cc/milkymist for the product13:17
wolfspraulI wish we can build more focus still, make the SoC stronger, get a really good Linux kernel to run on it, improve the toolchain, improve the Flickernoise app, improve the hardware, improve a lot of things13:18
jonandand... it's one thing to get a digital design to work, it's another to get through regulative testing (especially radio interference testing) and to have margins for variations in board impedance, operating temperature, component tolerances and so on.13:19
wolfspraulsure13:19
wolfspraulbut it's also nothing to be afraid of13:19
jonanddesigning is fun, the rest is why they pay you the salary.. :)13:19
wolfsprauland from a lot of industry experience, I can tell you - not every company is run like Apple13:19
wolfspraulin other words - there is *lots* of junk out there selling in high volume, and nobody cares13:20
jonandrun like Apple?13:20
wolfspraulI am pretty sure the engineering & build quality of the Milkymist One is already in the top 50% of consumer electronics quality that is typically selling in eu/us13:20
jonandwell, if you are in the fire-and-forget business you can get away with a lousy design. If you have to deal with 20% returns you better have decent margins to be able to afford the bad quality products... 13:21
wolfspraulI think it's not that easy13:22
wolfspraulmost hardware manufacturers are under a lot of pressure, mostly cost pressure13:22
wolfspraulbecause that's what consumers care about the most, and it goes all the way through to the component makers13:22
wpwrakjonand: (fire and forget) or have an efficient business card printing service, for when you make the weekly change of the company name ;-)13:23
wpwraki think you should get suspicious if a company has a day in its name :)13:23
jonandlol13:24
wolfspraulnah, I'm talking about something else13:24
wolfspraulsay you buy a computer from "HP"13:24
wolfspraulyou think anyone at HP knows anything about this computer?13:24
wolfspraulin the shiny TV ads they do13:24
wolfspraulbut only there13:24
wolfspraulin reality it is designed at some company A, which maybe using one or several reference designs from companies B and C13:25
wolfsprauland which are again outsourcing certification issues to companies D E and F13:25
wpwrak"designed in america" ? :) perhaps some case parts ...13:25
wolfspraulthen it's handed over to company G for manufacturing13:25
wolfspraulwhich is using subcontractors H I and J for parts of the volume13:26
wolfsprauland so on and so on13:26
wolfsprauland if you think that all of those really really care about operating temperaturs, board impedance variations, electromagnetic emissions, etc. oh well13:26
wolfspraulthen you may not have seen all too much into the work of those companies :-)13:26
wpwrakit's about having someone to blame. if you order 1000 laptops for your company and 20% are DOA, then you'll have a hard time explaining why you bought them from Happy Shenzen Wednesday Ltd. on the other hand, if you bought them from HP, even if they were still made by Happy Shenzen Wednesday, your ass is safe13:27
wolfspraulit's funny how company A proudly makes "a" board that passes an EMI test, and then hands over that board to company B for the "volume production"13:27
wolfspraulwhich will after a few days remove the 'unnecessary' parts that made the board pass the EMI test earlier13:27
wolfsprauland so on13:27
wolfspraulit's not just about returns, doa, 20%13:28
wpwrakyeah, there's worse13:28
wpwrakfailure in the field. unstable operation. incompatibilities. and so on13:28
wolfsprauljonand: I'm working in greater china for about 5 years now, and I think I've pretty much seen all the pieces now :-)13:28
wpwrakjonand: when wolfgang grows bored of computers, he'll become a successful writer of horror novels13:29
wolfspraulsure13:29
wolfspraulso some notebooks have an average life expectancy of 2 years, some more like 513:29
wolfspraulit's just super hard to pin it down to a specific company or missing quality check or unqualified staff somewhere in the chain13:30
pabs3so how does Qi deal with these issues?13:30
wolfsprauldon't understand13:30
wolfspraulwhat do you want to hear :-)13:30
wolfspraulmarketing speak: Qi is making the absolute *best* hardware you can possibly, ever, find - in the WHOLE WORLD.13:31
pabs3for example I assume Qi is vulnerable to stuff like what you said above: <wolfspraul> which will after a few days remove the 'unnecessary' parts that made the board pass the EMI test earlier13:31
wolfspraulmeaningless blurb, but it's what you hear from everybody else as well13:31
wolfspraulno, not at all13:31
wolfspraulwe are extremely vertically integrated13:31
wpwrakpabs3: qi doesn't have this sort of deep delegation13:32
wolfspraulas open hardware that's almost always included in the deal13:32
wolfspraulthe only other company that vertically integrated I'm aware of is Apple13:32
wpwrakpabs3: and wolfgang can probably smell a deal that's too good to be true by now13:32
wolfspraulalthouhg there may be other smaller ones too, of course. in vertical industries.13:32
pabs3I see :)13:32
wolfspraulwhat deal?13:33
wolfspraul:-)13:33
wolfspraulhardware quality is difficult to explain13:33
wolfsprauland honestly I think most people don't care that much, they just want to hear some fluffy words that makes them believe that what they buy is "good quality" :-)13:33
wpwrakthe usual "it's chine, so it must be cheap" meme. not sure if it has died out yet or if there are still lots of western companies that fall for it13:33
wolfspraulfair enough, since the actual situation is so complex and subtle, you don't want to hear about it13:34
wolfspraulso we also just say: Qi is making great quality hardware13:34
wolfspraul<1% returns13:34
wolfsprauldone13:34
wolfspraul:-)13:34
wolfspraulpasses "all" certs13:34
wolfspraulof course13:34
wolfspraulour hardware is perfect, the best13:34
wolfspraulalways13:34
wolfsprauldrop it from an airplane, and it will still work!13:35
wpwrak... as long as it doesn't hit anything. but that's covered by a different clause in the warranty13:35
wolfspraulpabs3: btw, if you make Qi hardware, which of course you can, then you automatically fall under our quality guarantee13:36
wolfspraulhow is that???13:36
wpwraki think his question was more about avoiding the practical pitfalls :)13:38
wolfspraulactually it may sound like a joke, but the quality 'handover' in reality is often not much different13:38
wpwraki guess a lot is based on reputation and perhaps past experience13:39
wolfspraulpeople like werner who start to philosophize over ever last word and punctuation in a spec or standard are rare in the industry13:39
jonandit's one thing to have to pay for expensive ferrites and common mode chokes because you try to filter your way below the EMI limit. It's another to have the correct series termination from start because you spent an hour or two simulating your address bus.13:40
wolfspraulthere are many cases where parts, standards, procedures are bouncing back and forth between a number of companies until "it fits"13:40
jonandI preach EMC compliance by design, not by filter/screening13:40
wolfspraulyep13:40
wolfspraulit won't survive the first day "on the line"13:40
jonandwhich is really just band-aid when you've produced thousands of PCBs already13:40
wolfspraulwell, mabe if the EE has a day off, on the first day it will stay there13:40
wolfspraulbut on the second when he's back it will be removed13:41
wpwrakUS client to chinese engineer, in the telephone conference: "did you read the spec ?" "Yes." "does it comply ? "Yes." ... :)13:41
jonandthing is that IMMUNITY noncompliance is what will kill you13:41
wolfsprauldon't worry we are all on the same page here13:41
jonandrouters that hang when not resetted after a brownout will kill that router brand name13:41
wolfspraulI think one promise of open hardware is that we can go for *higher* quality than usual13:41
wpwrak(that's more or less this sort of real life conference calls i've experienced. oh, and that was of course a non-affirmative "yes". the person in question didn't understand a single word :)13:42
wolfspraulbecause open designs can be shared and reused and better understood among more people13:42
wolfspraulwe are not just dreaming about this, but making functioning high-performance gear13:42
wolfspraulwhich we sell and service and take back on failure, etc. etc.13:43
wolfsprauland which passes fcc/ce emi compliance, and what not13:43
jonandhigher quality and also actually explain what's needed and why. regulations are not made up of evil people, they are a compromise on what will work reliably out in the field. the sad thing is that they tend not to explain WHY they are needed, which make them appear like a penalty rather than a help13:43
wolfspraulI agree13:43
wolfspraulstandards are important13:43
wpwraktracking the background of things is often rather hard indeed13:44
wpwrakand once that chain is lost, you're in the merry land of cargo cult and voodoo engineering13:44
wpwrakor standards-as-a-penalty13:45
wolfspraulI don't think like that13:45
wolfspraula standard is either good and thus followed, or ignored13:45
wpwraknaw you also get the bad ones you still have to follow. and some may actually be good, but they look bad13:46
wpwrakand if enforcement is nasty enough, everybody follows them, even if they're bad13:46
wolfspraulof course I say this with the liberty of looking from Beijing, which means that if the 20% of the world population really doesn't want product A because they actually enforce standards, then we sell it to the other 80% only :-)13:46
wpwrakno matter how much band aid you have to pour on that board13:46
wolfsprauland we make a version A+ with even higher margin for those 20%13:46
wpwrakthe high cost of those non-fake certificates :)13:47
jonandthose 80% can go reset their router every second day, I'm fine with that. 13:47
wolfspraulsure, but that's how bad regulations are flushed out13:47
wolfsprauland I agree that most are good13:47
wpwrakjonand: that's one minimum wage job. not too bad :)13:48
wolfspraulbecause if a regulation is meaningless, the 80% will find out and decide with their wallets13:48
jonandso you are located in Beijing?13:48
wolfsprauldon't underestimate those wallets13:48
wolfspraulyes13:48
jonandhow's the electronics industry there compared to shanghai?13:48
jonandshanghai or suzhou?13:48
wolfspraulthere's companies everywhere13:49
wolfsprauldon't understand13:49
wpwrakwolfspraul: i think it's more complex. people also attach different values to longevity, cost of failure, cost of replacement, etc.13:49
jonandwolfspraul: as in "level of competence, level of wages" and so on13:50
wolfspraulsure, but I think we all agree on A) following regulations and going for good standards b) identifying the bad/meaningless/stupid standards as such and trying to at least advocate them as bad13:50
wolfsprauland I think for the most part the quality of standards is actually good13:50
wpwrakwolfspraul: so if jonand really hates to have to rest his router, he may find having to spend 50% more a very good deal. meanwhile, the room full of routers in the Great Chinese Firewall may very well just have a few sidekicks that do nothing but look for lights that are "stuck" and press the little red button under it13:50
wolfspraulyeah but I think we are all on the same page13:52
wolfspraulwe all like quality products that we deeply understand and that we know we can trust and are reliable and follow the best standards, and and and13:52
jonand:)13:52
wolfspraulyet still at any moment we know any tiny resistor or cap on our super board may fail, for a variety of reasons13:52
wolfsprauland will we notice?13:53
wpwrakdepends :)13:53
wolfspraulwill one of our beloved standards now not be met anymore without us noticing?13:53
wolfspraulthat is very possible13:53
wolfspraulor do you check your home regularly for electromagnetic offenders?13:53
wolfspraul(for example)13:54
wolfspraulprobably not13:54
wpwraki'm probably the biggest of them within some 50 m bubble ;-)13:54
wolfspraulso in reality complex hardware is always subtle, and may fail in subtle ways. no matter how well we design it, manufacture, test, etc.13:54
jonandActually, my spectrum analyzer is powered on most of the time.. :)13:54
wolfspraulthere you go :-)13:55
jonandtypically not hooked up to any antenna though.. .13:55
wpwrakjonand: even better for finding offenders ;-)13:55
jonandbut again, immunity is the important thing. if your device locks up just because someone is flipping the light switch, the fridge/ac compressor is starting or your neighbour is welding... you will get customer complains killing any margins/profit you thought you had on your design13:57
wpwrakwolfspraul: component failure is random. but you can still influence how often it happens and what consequences it has. if you just say "anything can fail anytime anyway", then that's like saying that it's okay to sleep with a piece of radium under your cushion because anyone can get cancer anyway13:57
wolfspraulI am clear about that13:57
mirkokyak: regarding librt and dejavu-font-package i'll take a look now13:58
wolfspraulbut we speak in an open and logged channel, so it may be important to try to open up the minds of whatever unknown reader masses may read this one day13:58
wolfsprauland - every solder joint may fail at any time13:58
wpwrakjonand: i think the most important thing in our case is that the community can also help itself13:58
jonandand a device with bad signal integrity (lots of energy radiated as radio interference) is way more likely to be susceptible for say your cell phone transmitting at 1W peak13:59
jonandmore likely than a design with a proper layout13:59
jonandso I see it the other way around. If a device is quiet (and not filled with screens and ferrites) I know it is solid14:00
wolfspraulmodern computing hardware is just very subtle, and for the most part cannot self-analyze much if anything14:00
wolfspraulso there is always a huge variety coming off the production line, and from then on with every day that passes it only gets more diverse14:00
wolfsprauljonand: quiet?14:01
wpwrakjonand: continuously improving our design processes is certainly part of the concept14:01
wolfspraulI also think we have to go *way* beyond just thinking about the perfect design14:01
wolfspraulto testing software, during production and after a product is sold, testing under all sorts of stress, seeing how designs look like after some time of usage, etc.14:02
wpwrakjonand: even better, anyone can help. e.g., you know a lot about EMC. most people don't. we're not even sure how good the people to whom we outsource the M1 layout are in that regard. we believe they're good overall, but we might miss some weak spots. or a bad day, etc.14:02
wpwrakjonand: but the results are openly accessible. (the design files as well, but they use proprietary tools. that's why we want to move to kicad.) so you could review them, and tell us if you find anything suspicious.14:04
jonanda lot... well, I've learnt some the hard way by spending far too much time at regulatory test houses.. :)14:04
jonandwolfspraul: quiet as in "does not max out my spectrum analyzer when I approach it with a near field probe"14:04
wpwrakjonand: and once we learn some new rules, they can be shared with others who may not have much experience but still a good pair of eyes :)14:04
wolfspraulah, quiet on the spectrum analyzer, got it14:04
wolfsprauljonand: what spectrum analyzer do you use if I may ask?14:05
wpwrakjonand: (filled with screens and ferrites) you would have loved one project i bumped into in a former life. it had GPS and lots of interference issues. so piles of EMI filters were added and so on.14:06
jonandI have an old hameg. Been thinking about upgrading but then again I'm not really an RF guy, more into the digital domain. Not that those are too wide apart these days though.. :)14:06
wolfspraulcan you do us a favor and post the exact hameg model?14:06
wolfspraulwe are a bit obsessed about learning here :-)14:07
wpwrakjonand: (evil project) it also had another issue: USB would inexplicably fail from time to time. they thought it was a kernel issue. so i searched for that. didn't find anything overly suspicious. then we poked around signal integrity and such. nothing.14:07
wpwrakjonand: (evil project) then we suspected power distribution: power entered at the top of the CPU and then went in a merry almost-circle around it. so we added beads, caps, etc., to fix that routing. still nothing.14:08
jonandwolfspraul: http://www.hameg.com/0.45.0.html?0= <-- HM501414:08
wolfspraulthanks!14:08
jonandIf you are to buy anything I would suggest to get one which covers up to 2.6G14:09
jonandthis one is intended for precompliance EMI tests and is limited to 1G14:09
wpwrakjonand: (evil project) finally, on the day the EEs would sign off the layout for the next (and probably last) try, i stumbled into their layout review meeting. there, i saw the following:14:10
jonandbut then you miss out the 2.4g band and also the LNB downlink from your satellite dish14:10
jonand950-215014:10
wpwrakjonand: (evil project) CPU had its XTAL connections in the 4 o'clock position. the crystal was located in the 10 o'clock position, with traces going all the way across the CPU, and even nicely to the other side of the PCB and back.14:11
jonandwpwrak: did you laugh or cry? :)14:12
wpwrakjonand: (evil project) to top this, right under the xtal traces, there were the DRAM signals. naturally, no ground in between or left or right.14:12
wpwrakjonand: i was actually quite happy :) we had spent something like two months on that problem, and all the band aids we had thrown at it seemed futile. when i saw that mess, i know we had found it :)14:13
jonandactually, routing clock traces across the board is not that bad, IF you 1. keep your signal return in a solid ground plane below the trace 2. stay on one layer 3. have proper termination14:13
wolfsprauljonand: here's a milkymikst one emi document, any feedback would be more than welcome http://en.qi-hardware.com/w/images/1/1a/Reichl_milkymist_one_tests_11000301.pdf14:14
jonandand 4. stay away from board edges14:14
wpwrakjonand: we couldn't clean it up completely at that time, but we could at least remove the very worst offenses. like pushing the traces a few mm to the side. and that already was enough to make the thing work well enough to proceed. (the project died later for other reasons, so i think the design was never fully cleaned up, though)14:15
wpwrakjonand: (routing clock) yeah, there were none of these niceties. plus, this was to the "naked" crystal. not some nice differential digital signal or such.14:17
wpwrakjonand: that design was more or less a textbook example illustrating everything you should never do14:18
wpwrakjonand: one problem was that all the EDA things were behind proprietary tools. so already getting printable schematics was difficult. and i hardly saw the layout at all (before that fateful day). why the EEs who had had all this right in front of their noses the whole time didn't see it is a bit of a mystery to me, though.14:20
jonandwolfspraul: wow, pretty low emissions in that report! 14:28
jonandso is this the current layout? http://milkymist.org/mmone/rc3_gerber.tar.bz214:29
mirkokyak: hmm.. the font stuff gets complicated - it was tried to get fixed by mb however i reverted that commit since it broke other stuff14:33
jonandthe ksz8001 contains an ibis model... "let me download and have a look".. 14:34
kristianpaullow enought to allow us easilly to add built-in antennas for GPS and posibly other RF aplicationsn?14:39
kristianpaulhi jonand :)14:39
wolfsprauljonand: yes from the name that looks like the current gerbers14:46
jonandkristianpaul: to know that you need to know what you have at GPS and the other RF bands you are considering.. therefore my advice on getting a spectrum analyzer covering the popular bands... 14:50
wpwraknow, where to find a cheap one :)15:09
kristianpaulrtl-sdr wont work for that?..15:11
wpwrakyou mean something like USRP ? it does, but it has its limits15:16
kyakmirko: i see.. probably it makes sense to combine it back into a single package? Usually the fonts wouldn't be installed on routers, so...15:19
kristianpaulwpwrak: yes15:21
wpwrake.g., lack of calibration, quite limited bandwidth, and you also need several RF frontends if you want to cover the whole spectrum to 2.x GHz (the latter aspect has gotten a bit better recently, though. now you only need two boards for most of the interesting frequencies)15:21
mirkokyak: hmm.. not sure yet15:25
wpwrakbut yes, it's far better than nothing :)15:26
Action: kristianpaul wonders if there are programable LNA's20:33
wolfspraulwpwrak: with rtl-sdr kristianpaul meant this one http://sdr.osmocom.org/trac/wiki/rtl-sdr23:11
wolfspraulit's a 10 USD usb dongle, which although receive-only seems to give you a good starting point into gnuradio & sdr23:11
wolfspraultuner goes from 64mhz to about 1700mhz23:11
wolfsprauldemodulator can be configured to send raw samples to the host23:12
wpwrakoh dear :)23:12
wpwrakUSRP looks rather powerful in comparison ;-)23:12
wpwrakbut yes, the principle is the same. just that rtl-sdr doesn't cover some of the most interesting frequencies23:13
wolfspraulsure, but at 10 USD it allows people to first focus on the software side23:13
wolfsprauland then when they really understand the various subtleties, they can uptick their hardware as needed23:13
wolfspraulI do think that makes a lot of sense23:13
wpwrakthe price in unbeatable, agreed. and it's sufficient to, say, listen into FM or some GSM23:15
wpwraks/in/is23:15
wolfspraulor local TV, its original purpose23:15
wolfspraulor maybe taxi radio, police radio? satellite phones?23:15
wolfspraulit's 20 USD by the time someone with some english skills has put it on an international shopping site23:16
wpwrak:)23:17
wpwrakpity it doesn't go a little higher. 800 MHz more and there would be lots of ISM band fun23:19
wpwrakwell, lots more ISM band fun23:19
wolfspraulmaybe one or two ic gens later? :-)23:19
wpwrakif they don't pull the feature :)23:20
wolfspraulthere are 2 chips left now, a realtek demodulator/soc, and an elonics tuner although that one seems replacable with alternatives from fitipower, noxon, etc.23:20
wolfspraulsure they can, it's a more or less typical "found a chance" reverse engineering effort23:20
wolfspraulbut so what, it gets people started, they learn, and then become more agile and more independent later23:21
wpwrakwhen the products approach EOL, there may be an opportunity to buy up a lot of them and sell them with a nice margin once they get de facto unobtainable23:22
wolfspraul(they have another, I believe even s-6 fpga based osmosdr board in the making, including tx, but the discovery of this 10/20 USD dongle distracted them a little. so the alternatives are already in the making...)23:22
wolfspraulI'm not so pessimistic at all, no need to do that.23:23
wpwrak(distraction) i can imagine :)23:23
wpwrakit would be a service23:23
wolfspraulics actually rarely go eol, most of the time the new chips are just better for everyone - and - a lot of ic companies are handing over old chips to specialized small companies that are making old chips 'from the archive' for as long as there are customers willing to pay the premium23:24
wolfspraulthat's not always true, for example if a chip is closely tied to a particular manufacturing technology which is also being dismantled or upgraded as the new gen comes out23:25
wpwrakyes, but once the boards don't get made anymore, the overall cost jumps up. even if you can still get the chips.23:25
wolfspraulbut in a lot of cases it's true, smaller more niche chips23:25
wolfsprauloh sure, costs go up and up if you step outside of the big stream23:25
wpwrakwell, SDR is the future. good to see it get more accessible.23:26
wolfspraulyes23:26
--- Tue Mar 27 201200:00

Generated by irclog2html.py 2.9.2 by Marius Gedminas - find it at mg.pov.lt!