#qi-hardware IRC log for Wednesday, 2011-08-17

lemayare there any plans for the milkymist involving GPS?01:58
wolfspraulright now we just hookup the sige front-end rf ic and see whether we can get it to work01:58
wolfspraulno big strategy or product plans01:58
wolfspraulsige sent us one evb, which went to kristianpaul who hooked it up to his milkymist one01:59
wolfspraullemay: have you worked with namuru or osgps before?02:01
lemayNo - never heard f either02:06
lemayI've done a lot of work with GPS though02:07
lemayfrom the RF front end to the tracking loops02:07
wolfspraulgreat02:07
wolfspraulif you stay here a little and timezone wise you and kristianpaul are both up I'm sure he might have a question for you02:08
wolfspraulseems he's not online right now, don't know what time it is in Colombia...02:09
lemaycool :)02:09
lemayI'd be happy to chat02:09
qi-bot[commit] Xiangfu Liu: Nanonote: ignore HUP signal (master) http://qi-hw.com/p/gmenu2x/64108ab02:10
qwebirc86657Review of KiCAD  http://dangerousprototypes.com/2011/08/16/kicad-open-source-pcb-layout-package-reviewed/02:38
qi-bot[commit] Xiangfu Liu: gmenu2x, update and immediately stop then poweroff (master) http://qi-hw.com/p/openwrt-packages/d320abc02:40
wolfspraulqwebirc86657: thanks for sharing!02:48
qi-botThe build was successfull, see images here: http://fidelio.qi-hardware.com/~xiangfu/compile-log/openwrt-xburst.full_system-08152011-2339/02:52
kristianpaulhello lemay ! :)02:59
kristianpaulwich kind of tracking loops had you worked with?03:00
wolfspraulkristianpaul: he's out to dinner now :-)03:01
kristianpauloh, ok03:01
kristianpaulquick update, them03:08
kristianpaullemay: namuru correlator (actually kinda same tp gp2021 from zarlink) is ported now to milkymist03:08
kristianpaulmissing and not implemented yet in software a proper tracking and pull-in algorythm that finally allow us to get navigation data :)03:09
kristianpaullater care about fixes :)03:09
kristianpaulso osgps wich stands to open source gps, was developd/used ten years or so ago with a gp2021 chip hookedup to a ISA card on a 100mhz computer03:12
kristianpaulthe code is not the best you see, i'm not a skilled coder, but still dificult to get understan how it works as too  many things are in the same file.. well03:12
kristianpaulosgps seems to implement a PLL-like methog for tracking03:13
kristianpauldunno how it works in detail03:13
kristianpauland btw how yo get to here ;)?03:14
lemayhah, I have to dust off those memories03:14
lemayI bumped into wolfspraul03:14
lemay:)03:14
lemaywell, the tracking loop I've done was pretty much like a PLL as well03:15
kristianpaulhttp://www.colorado.edu/geography/gcraft/notes/gps/gif/bitsanim.gif03:15
lemayyea, correaltion03:16
lemayneat gif03:16
kristianpaulthat above acording to the gp2021 datasheet can easilly achieved by a loop and namuru i guess03:16
kristianpauli'll try that this weekend or earlier03:16
kristianpaulbut03:16
kristianpaulat least graph it with gnuplot or similar03:17
kristianpaulonce i had a clear correlatio peak03:17
kristianpaulthe hunting star in order to pull-in http://home.earthlink.net/~cwkelley/receiv3.gif03:18
kristianpauls/star/start03:18
kristianpauland i'm not compley aware or understand a proper algortym for it.03:19
kristianpaulof course i'm now there ir no silver bullet on that as it depents on the aplication03:20
lemayDoes the namuru have a complete RF front end?03:20
kristianpaulnope just correlator03:20
kristianpaulactually it still need aid from software to work, is not a complete base band solution03:20
kristianpaulhere is where milkymist soc plays a role :)03:21
lemaywhat are those sma's for? IF?03:21
kristianpaulcurrent frontend is a SE4162 from SiGE03:21
kristianpaulir provides real and complex samples03:21
kristianpaulcurrently working on real mode, 16Mhz sampling clokc 2.556 IF and 2 bit Sign/mag out03:22
kristianpaullemay: wich sma's exacly?03:22
kristianpaulfrom wich pic? 03:22
lemayheh, right - http://www.dynamics.co.nz/index.php?main_page=page&id=903:23
lemayI forgot I got there from google and not from you showing me that03:23
kristianpauloh wait, le me drop some links03:23
kristianpaulwww.dynamics.co.nz/media/Namuru_GPS_datasheet.pdf <- namuru datasheet03:24
kristianpaulthis is the EVB that wolfspraul talked about http://en.qi-hardware.com/wiki/File:SiGE_EVB_Zoomed.jpg03:24
kristianpaulhere some sumary http://en.qi-hardware.com/wiki/GPS_Free_Stack03:25
kristianpaullemay: was your work related to full software processing?03:25
kristianpaulwas it offline or "real time" processing?03:26
lemayreal time03:26
kristianpaulyay !03:26
kristianpaulso far the _only_ achievement about signaling was confirm code in the signal i sampled for offline prossing03:27
kristianpaulafaik i never got track, i guess because i wasnt aware osgps dint worked with complex samples..03:28
lemayyou successfully correlated CA code in post-processing?03:28
kristianpaulwith namuru?03:28
lemayuh, heh03:29
kristianpaulin short words i still on acquisition03:29
lemayright03:29
lemaywhat sort of data are you working with?03:30
kristianpaulfrom namuru?03:31
lemayI mean the RF03:32
kristianpaulcurrently sige rf fronted provides real samples,  2 bit sig/mag 03:32
kristianpaul2.556Mhz IF  16.684 mhz sampling clock03:33
lemaygotcha - you already told me that, huh03:33
lemay:)03:33
kristianpauloh no, sorry if i missudestand you, too many info and i'm soon (1rh or so) off bed03:34
kristianpaulyou are in canada right?03:34
lemayso, since you're working with real samples, your next step is to try to correlate using osgps?03:34
lemaycalifornia03:34
kristianpauloh, nice03:35
kristianpaulabout osgps well not now, i did in the past some offline processing, as i was using milkymist just for data acquisition03:36
kristianpaulbut now i have namuru on milkymist, so next plan is detect correlation peak03:37
lemaysounds good03:37
kristianpauli hope ;)03:37
lemaydoes the namaru software take care of all of that?03:38
kristianpaulnamuru is implemented in the fpga, lets said is the hardware DSP for all this, afaik no current software support for it that i'm aware off03:38
kristianpauls/off/of03:39
kristianpaulso no no care of all that03:39
kristianpaulit will when the software side to drive the namuru will be developed/ported? for milkymist03:40
kristianpaulthen we can call it milkymist  gps baseband soc i guess ;-D03:40
lemaygotcha. So you're going to interface the FPGA on the milkymist with the RF front end - the SE4162T-EK1 - and use it to track GPS03:41
lemaythis sounds plausible to me03:41
kristianpaulyes thats already done03:41
kristianpaulactually i hope from now that is missing is software side03:41
lemayYea, I mean the whole thing - the tracking GPS part - that's plausible03:42
lemaywhat sort of CPU will you use?03:42
wolfspraulhey, Milkymist is a CPU :-)03:42
kristianpaultell is a SoC..03:42
lemaysomething in the milkymist - the LatticeMico32?03:42
kristianpaulmilkymist uses a lattice  mico32 03:42
kristianpaulyes03:43
kristianpaulbut yes CPU is okay i think03:43
lemayhaha, I don't know enough about the system architecture :)03:43
lemaywell, I think it will work03:43
kristianpaulsure it will !03:43
lemayI designed a front end for a system that is very similar03:44
lemaycorrelators in FPGAs, and controlled by an x86 running windows, of all things03:44
lemayits a Dell with a Virtex 403:44
kristianpauls/tell/well03:45
kristianpaulwow wow, sounds fancy :)03:45
kristianpaulis it pusblished somwhere?03:45
lemayyea, its nifty03:45
wolfspraullemay: can you share some sources? :-)03:45
lemayunfortunately I can't03:45
lemaybut I can try to help you03:45
kristianpauli'm open now to learn about pull-in algorythms03:46
lemayI understood the tracking loops pretty well at one point, but it will take me a bit to shake off the dust03:46
kristianpaulbtw the software on the x86 worked upon accumlators? or implemented PLL directly on FPGA?03:46
kristianpauli was told that was posible too03:47
lemayit worked on the early prompt lates from the fpga03:47
kristianpaultake your time lemay , and hang on here of course03:47
kristianpaulgreat, on namuru we have same :)03:47
lemayit updated the phase shift register based on those sums03:48
lemayand I suppose the code replicators, too03:48
kristianpaulcode replicators?03:48
lemayyea - for the crrelation03:49
kristianpaulreplicator = generator ?03:49
kristianpaulah yeah, replica code, yes yes03:49
kristianpaulgo ahead, sorry for interrupt03:49
lemayI've got to go afk for a few minutes03:50
lemaybe back in 5 or so03:50
kristianpaulok i think i'm going bed now, my head is not feeling good...03:52
lemayok03:52
lemaynice talking to you03:52
lemayif you come up with any questions let me know03:53
lemayI am in #elphel a lot03:53
kristianpaullast question for you is about how you managed to your software be wideband and narrow band,03:53
kristianpaulalso how to manage doppler, and when the receiver is moving03:53
kristianpaulokay, nice to meet you too lemay03:54
lemayWell, your sampling rate will allow you to adjust for doppler03:54
kristianpaulread you later03:54
lemayand you need to tune your tracking loops depending on what dynamics you want03:55
kristianpauland how to manage that satellite moves... i mean i have this early promt late, but how i do correlate that data? is tha pull-in about?03:55
kristianpauli really need to understand an algoythm for it..03:55
kristianpaulyes i need to learn how in depth, at least to implement that for namuru, as i dont get that part clearly from osgps code... :|03:56
lemaythe satellite motion is part of the doppler estimation03:56
kristianpaulohh03:56
kristianpauli tought was apart03:56
lemayI mean, that thing is moving at a jillion miles per hour, right?03:56
lemayso it has a doppler relative to you, even when your stationary03:57
lemayyour tracking loops just care about the combined doppler03:57
lemayyour combined doppler will be fairly insignificant compared with the correlation period03:57
lemayor, your delta doppler03:58
lemayI just started spouting gibberish, huh03:58
lemayso, you can tell what the combined doppler is, in general03:58
kristianpaulso whats the main issue about tracking? i mean once i detect the signal i play with... slewing code? or fixing local carrier nco values?03:59
lemaythe main issue about tracking is replicating the correct code and carrier04:03
lemayyou look at your early, prompt, and late correlation sums, and it tells you whether or not you are right on the signal, or if you are a little bit off04:04
kristianpauli see, not sound complicated :)04:05
lemaybased on that, you change the phase of the carrier that you are generating and you move the code forward or backwards04:05
lemayheh, are you being ironic or not? I can't tell.04:05
kristianpaulno no, no ironic04:05
lemayyea, conceptually it is not bad04:06
kristianpaulthe faster the better i guess04:06
lemayso the PLL - phase locked loop - generates a carrier phase based on the early prompt and late sums (if I am remembering all this right.)04:06
lemaywell, you have to correlate for so amount of time to generate your eraly prompt and late sums04:07
lemaylike, 20 milliseconds is standard04:07
kristianpaulyes04:07
lemayso you get your updates at 50Hz04:07
kristianpaulyes, thats navigation rate per satellite right?04:08
lemayyou update your tracking loops at 50hz04:08
lemaysounds right.04:08
lemaybut thats different from the tracking loop04:08
lemaythe tracking loop is adjusting the PLL at 50Hz, based on those correlation times04:09
kristianpaultracking loop update in less than a 1ms i remenber, right?04:09
kristianpaulhum..04:09
lemaythe nav data is basically checking the sign of the prompt signal04:09
lemaywell, depends on your implementation04:10
lemayif Namuru does 1ms that's great04:10
lemayand maybe that's normal, I haven't thought about this in a while - maybe tomorrow I'll be saying to myself, 'yea, duh, of course its 1 ms....'04:11
kristianpauli think is less 1ms is too tight, but yes it does04:11
kristianpaulhe sure,04:11
lemayso, narrowband vs wideband - I am not sure I understand the question04:12
lemayI'm pretty sure that we 04:18
lemayheh, hit enter by accident :)04:19
kristianpaulmom04:23
kristianpaulhttp://www.datasheetcatalog.org/datasheet/zarlinksemiconductor/zarlink_GP2021_JAN_01.pdf page2204:25
kristianpaulwell,i said by now, off bed now04:28
kristianpaulchao :)04:28
lemayo/04:28
lemayYea, that sentence is kind of strange. I'd ignore it.04:28
lemayEssentially you change modes when you go from acquisition to tracking - in acquisition you are searching the entire code/doppler space, and once you have acquired, you don't need to search the doppler space - just the early prompt lates04:30
rejonhere is a qi news item for you wolfspraul about shanzhai, blahblah http://www.iftf.org/node/394304:31
rejonmost of my comments had to be removed because were too personal and stinging04:31
rejonesp. the one about the open hardware logo being a broken gear04:32
wolfspraulha04:33
wolfspraulyou are right, never thought about it04:34
wolfspraulbroken gear :-)04:34
wolfspraulrejon: phew, so much text [iftf] - do I have to read all that?04:39
wolfspraulI scanned over Bunnie's comments and I share all of those views.04:40
rejonno04:40
rejonits pretty comprehensive look at shanzhai04:40
wolfspraulBunnie does have a real and deep understanding of these things.04:40
rejonconcludes that chapter04:40
rejoni think i just repeat most of the things you put in my head04:40
rejonbut my comments were mostly removed by my request04:40
rejoni wanted that gear one to go in04:40
rejonanyway, next04:41
rejonjust an item for the news04:41
xiangfuwpwrak, someone ask atBen in mailing list: (1) can it be connected to a Arduino microSD shield? I am using Digi07:42
xiangfuXbees at the moment but I would rather switch to atben if possible07:42
xiangfuwpwrak, I don't know  how Arduino software drivers works. so don't know how to answer :(07:43
wpwrakno, it won't work with the arduino microSD. arduino doesn't provide all the signals on the uSD.07:45
wpwrakand of course, you would also need to write a driver, etc.07:45
xiangfuok. got it07:46
qi-bot[commit] Werner Almesberger: bitcmp/: little utility to find which bits differ between two files (master) http://qi-hw.com/p/wernermisc/08a13cd10:00
qi-bot[commit] Werner Almesberger: bitcmp/bitcmp.c: fixed fencepost error (master) http://qi-hw.com/p/wernermisc/78d9fda10:11
`antonio`wpwrak, I am trying to set up three nanonotes with atben, how do i set up the iz assoc and dirtpan? 11:03
wpwrakiz assoc should be the same on the two non-coordinators (they will receive different addresses)11:05
wpwrakdirtpan is point-to-point, so you'll need two dirtpan instances on each node.11:05
wpwrake.g., on the coordinator:11:05
wpwrakdirtpan 777 1 8001 'ifconfig $ITF $IP1 dstaddr $IP2 up'11:06
wpwrakdirtpan 777 1 8002 'ifconfig $ITF $IP1 dstaddr $IP2 up'11:06
wpwrakon the node with short address 8001:11:06
wpwrakdirtpan 777 8001 1 'ifconfig $ITF $IP2 dstaddr $IP1 up'11:06
wpwrakdirtpan 777 8001 8002 'ifconfig $ITF $IP2 dstaddr $IP1 up'11:06
wpwrakand on the other:11:06
wpwrakdirtpan 777 8002 1 'ifconfig $ITF $IP2 dstaddr $IP1 up'11:06
wpwrakdirtpan 777 8002 8001 'ifconfig $ITF $IP2 dstaddr $IP1 up'11:06
wpwrak(i hope :) have't tried three nodes myself yet11:07
`antonio`wpwrak, ok :) i'll let you know how that goes !11:08
jivsHi wpwrak, One of the atben is giving this error14:04
jivsi check the nanonote detects other atben, so i suppose kernel is fine14:04
jivsi tried on another nanonote as well same error14:04
jivsat86rf230 spi32766.0: Non-Atmel device found (MAN_IDff ff)14:04
jivs[    3.240000] at86rf230: probe of spi32766.0 failed with error -2214:04
jivswhat it could be? anything related to atben hw?14:04
`antonio`wpwrak, 3 nanonote connected together with atben, that worked, thanks14:43
wolfspraulwow14:44
wolfspraul`antonio`: three?14:44
`antonio`yes14:45
Aylainteresting14:46
jivs4 of them now!14:55
wpwrakjivs: (error) sounds like the atben card is missing or makes bad contact15:28
wpwrakwhee ! largest atben network on the planet ! :)15:29
Action: kristianpaul feels bad not buying/supporting some atben..15:30
wpwraktraitor !!! :)15:30
jivswpwrak, i tried few times and on few ben nanonotes..15:31
jivsbut i will try again if any device can detect it.. 15:32
kristianpaulno rush with tuxbrain. but paying lot of taxes make me keep away :(15:36
kristianpaulmay be sharism can sell me soem atben? :)15:37
kristianpaul`antonio`: what are your plans with the atben?15:40
`antonio`kristianpaul, I am testing atbens as part of a project and hopefully tomorrow i'll do a video15:44
`antonio`wpwrak, for that jivs error: one atben is faulty.15:45
wpwrak`antonio`: :-(15:47
wpwrak`antonio`: if you want to analyze what's wrong, you could run the production test software on it15:49
wpwrak`antonio`: most likely, the GPIO test would spot something15:49
wpwrak`antonio`: the test is in this script: ben-wpan/prod/atben 15:55
`antonio`ok 15:57
`antonio`i'll let you know how that goes15:58
wpwrakthere's actually very little that can go wrong on atben. any failure wold have to be a short (foreign particle ?) or a solder joint that failed15:59
wpwrakfor failed solder joint, only a joint on the transceiver itself or the crystal would make it become unresponsive16:00
wpwrakfor a short, add the capacitors as candidates16:00
`antonio`interesting !16:05
wpwrak`antonio`: setup and usage instructions for the test system are here: http://downloads.qi-hardware.com/people/werner/wpan/prod/16:21
wpwrak`antonio`: in your case, you don't need the atusb side (i.e., later tests of the atben would fail without atusb to talk to around)16:21
`antonio`wpwrak, i went through that already last week and I had some problem, i'll let you know if I got that working16:27
`antonio`also because i'll need your help :) 16:29
wpwrakhehe :)16:30
qi-bot[commit] Werner Almesberger: bitcmp/bitcmp.c: added indication of direction of bit flip (1 -> 0 or 0 -> 1) (master) http://qi-hw.com/p/wernermisc/dd0c4ec16:36
methril_workwpwrak, in your fw adventures do you ever have stack problems?16:43
wpwrakmethril_work: so far, i never hit any. at least not that i know ;-)16:45
methril_workwpwrak, i`m in this nightmare at work... 16:46
methril_worki know because a wonderful processor feature that resets the preocessor if a StackOverflow occurs16:46
wpwrakcan you disable the reset ? (-:C16:48
methril_workyes, but then it gives undetermined behaviour16:49
methril_workit`s worst disabling it16:49
wpwrakexcellent. then you can blame the hardware :)16:50
methril_worki balme all the time!! :)16:50
methril_works/balme/blame/16:50
wpwrak:)16:50
wpwrakin hardware we distrust :)16:50
methril_worknot in this HW :)16:51
kristianpaularggg cannot exec `cc1' i hate rpm NOW17:21
kristianpaulwhat's license for this mmtp_i2l.pdf btw¿18:27
kristianpauls/¿/?18:27
lekernelwtfpl19:50
kristianpaulno other license please20:09
DocScrutinizeryay exception on stack overflow - cool feature20:13
wpwrakPIC, i guess ? :)20:15
lekernelactually I wonder why no other arch implements this SPLIM register20:16
lekernelit's not even particularly hard to do20:16
lekernelwe should add that to lm32 :)20:17
wpwraklekernel: why ? the MMU will catch it nicely ;-)20:17
lekernelSPLIM is much easier to support in RTEMS than a MMU-based system20:18
lekerneland it will take ages before Flickernoise runs flawlessly on Linux20:20
Action: wpwrak happily notes the now the possibility of running flickernoise on linux is being considered :)20:21
wpwrakbut yes, certainly nothing trivial20:21
lekernelI have nothing against Linux... except that it doesn't work, and getting it to work takes 50-100x as much time as RTEMS for equivalent tasks20:23
wpwrakbut when it works ... :)20:24
kristianpaulpeople will blame the 80Mhz cpu..20:26
wpwrakblame or dislike ?20:26
wpwrakisn't there still quite a bit of spare room in the fpga ? maybe you could add more cores ;-)20:27
kristianpaulyes, sorry. dislike20:27
kristianpauloh sure20:27
kristianpaulall is posible ! ;)20:27
wpwraksimplify it and make a decacore. more than all the other big players ;-)20:28
lekernelin fact, a decacore might work right now20:29
wpwrakadd some branch elimination logic for the bogomips loop, and you'll have stellar values there, too ;-)20:29
lekernelexcept that there's no software support for it ofc20:29
wpwraklekernel: who cares about sw support ? it's all marketing :)20:29
kristianpauljust lack software support, what about hdl part? is that easy as just adding another lm32 to the shared bus?20:31
wpwrak(branch elimination) when you take a branch, remember where it went and what the condition was. then have a comparator on the program counter that implicitly executes the branch when incrementing into the address of the branch instruction iff the condition is met. voila, removed at least 1 instruction cycle :-)20:33
wpwraknow quick, where do i file the patent :)20:33
lekernelkristianpaul, if you don't want cache coherency (which could be a problem depending on the software) yes20:34
lekernelif you want cache coherency... you have to dig into the CPU pipeline, and since people seem already afraid of the simpler MMU this has little chance of happening20:34
lekernelthough the LM32 cache is write-through, so all you have to do is broadcast writes to all cores. not too hard.20:36
wpwraki somehow feel that we may see more cores pop up before too long :)20:37
lekernelwpwrak, phew, I'm not that optimistic22:06
lekernelamong the current people I don't think anyone would pull that off22:07
lekerneland wrt finding new people, my google analytics reports still feel like a spit in my face22:07
lekernelso... it will be hard22:07
wpwraklekernel: ah, i was thinking that you might have had an inspiration of the "hey, this would be EASY" kind :)22:08
wpwrak(followed by a few hours of furious hacking. then a few more days, realizing that it wasn't all that EASY, but still doable. etc. ;-)22:10
lekernelcan you believe it? the elektor article, run in 3 different languages (and soon 4), generated so far exactly 2 people following the project and 1 board sale22:12
wpwrakwow. does elektor have so little reach these days ?22:15
lekernelseems so22:15
lekerneleven slashdot had better results (and it took less time to write the article, too), despite the trolling22:15
wpwrakheh :)22:16
wpwrakwell, a good article is also something you can point people to and you can reuse some of the material. so it's not a waste of time22:16
lekernelso atm i'm trying xcell, aimed specifically at people who are not afraid of fpga's to start with22:17
lekernelsome articles are also "syndicated" in publications like eetimes22:18
wpwrakyeah. maybe that'll get some more developers aboard22:18
lekernelso, atm I rather feel the need to fix that huge unpopularity problem rather than mess with multicore lm32's ...22:19
wpwrakmaybe multicore will get people excited :)22:24
wpwraki think once linux runs well, this may help. lowers the barrier of entry quite a bit if you have a familiar operating system.22:25
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