2014-08-24 00:00 according: Uin: [0..Umax[; output:b0,b1,b2 [000, 001, 010, 011, 100, 101, 110, 111]; 001:="Uin > Umax/8 * 1", ... , 111:="Uin > Umax/8 * 7; comparator0-out=b0:= " Uin > ( (Umax/8 * 1) + {b1 * ( Umax/8 * 2) } + {b2 * ( Umax/8 * 4) } ) "; comparator1-out=b1:= " Uin > ( (Umax/8 * 2) + {b2 * ( Umax/8 * 4) } ) "; comparator2-out=b2:= "" Uin > (Umax/8 * 4)" 2014-08-24 00:03 speed of conversion aka settle time for LSB: (number of bits) * (comparator propagation delay) 2014-08-24 00:04 so for an 8bit converter at 25MHz I need opamps with a Ft>200Mhz 2014-08-24 00:08 hmm, http://de.wikipedia.org/wiki/Analog-Digital-Umsetzer#Pipeline-Umsetzer still isn't it 2014-08-24 00:09 I only ever seen parallel flash A/D with 2^N comparators for N bits: http://de.wikipedia.org/wiki/Analog-Digital-Umsetzer#Echter_Parallelumsetzer 2014-08-24 00:09 wonder why. I hardly could have invented a new type of A/D converter, could I? 2014-08-24 01:13 pcercuei has quit [Quit: dodo] 2014-08-24 01:40 Textmode has joined #qi-hardware 2014-08-24 01:46 mth has joined #qi-hardware 2014-08-24 01:52 so this is what's really behind the algorithmic captchas of qi-hw: http://www.smbc-comics.com/index.php?id=2259#comic 2014-08-24 01:56 would you have guessed that the first four panels of this are actually true, at least according to wikipedia ? http://www.smbc-comics.com/index.php?id=2260#comic 2014-08-24 03:56 uh 2014-08-24 03:56 did you eventually settle on a DIY scope or what? 2014-08-24 03:57 DocScrutinizer05: re satellite: no, just a regular fuckup, it happens every so often 2014-08-24 05:12 rz2k has joined #qi-hardware 2014-08-24 05:16 wpwrak: hmmmm, that looks fine: http://www.eevblog.com/forum/testgear/first-impressions-and-review-of-the-rigol-ds2072-ds2000-series-dso/?action=dlattach;attach=35175 2014-08-24 05:17 (300some k) 2014-08-24 05:38 xiangfu has joined #qi-hardware 2014-08-24 05:48 xiangfu has quit [Ping timeout: 272 seconds] 2014-08-24 06:00 xiangfu has joined #qi-hardware 2014-08-24 07:24 yes, segmented memory is sexy ;-) 2014-08-24 07:46 btw, here's the siglent monste thread i mentioned: http://www.eevblog.com/forum/testgear/siglent's-new-product-msosds2000-series/ 2014-08-24 07:46 (well, a small monster - only 44 pages) 2014-08-24 07:47 now has spawned a tech support thread: http://www.eevblog.com/forum/testgear/siglent-technical-support-join-in-eevblog/ 2014-08-24 08:11 aah fine! I already made my way through rigol and spotted the MSO2102A 2014-08-24 08:12 ((looks fine)) it's actually a "printout" of an animated gif, sth that the DS2k rigol can do without any help 2014-08-24 08:24 wej_ has joined #qi-hardware 2014-08-24 08:25 wej has quit [Ping timeout: 250 seconds] 2014-08-24 08:31 xiangfu has quit [Remote host closed the connection] 2014-08-24 08:37 hmm, the siglent do not get good reports 2014-08-24 08:37 also the mech UI looks somewhat less well thought to me 2014-08-24 08:38 the level knob seems to be the biggest mechanical issue 2014-08-24 08:38 less buttons, so more submenu levels and more button pressing to do the same setting 2014-08-24 08:39 there are also some firmware features that clearly need more work. e.g., navigation through 50k segments could take you minutes :) 2014-08-24 08:41 segments? 2014-08-24 08:41 like "let's only record data while things happen"? 2014-08-24 08:42 yes, basically that. take a snapshot on each trigger. 2014-08-24 08:42 oh cool 2014-08-24 08:42 here's a SDS2000 vs. DS2000 comparison: http://www.eevblog.com/forum/testgear/review-siglent-sds2304-a-comparison-of-features-with-rigol-ds2000-series/ 2014-08-24 08:43 the DS1000Z also has segments, but weaker and optional (so its price either jumps in a higher category or you have to hack it) 2014-08-24 09:09 Textmode has quit [Quit: "It was one dev, naked in a room with a carton of cigarettes, a thermos full of coffee and bourbon, and all his summoned angels."] 2014-08-24 09:09 pcercuei has joined #qi-hardware 2014-08-24 09:52 kilae has joined #qi-hardware 2014-08-24 12:14 wolfspraul has joined #qi-hardware 2014-08-24 13:17 wpwrak: thanks for this useful link to the comparison video. It's absolutely clear now that siglent is unusable 2014-08-24 13:47 slightly better hw (except for the UI aka knobs) but terrible firmware 2014-08-24 13:50 ;-) seems that rigol had similar problems when the ds2000 came out. the big problem with the ds2000 is the 2 channels limit. else it would be perfect. 2014-08-24 13:56 as already elaborated upon, I'm way more happy with 2ch-A+16ch-D 2014-08-24 13:57 you hardly ever need *analog* recording/watch of more than 2 signals, when you can watch a 16 signals on logical level in parallel and even trigger on them 2014-08-24 14:00 the waveforms/s capture rate of siglent is sometimes abysmal. The 30min dial-wanking to move form frame 1 to frame 80000 is plain ridiculous. The analysis + playback of history is useless on just one speed and incredibly slow analysis 2014-08-24 14:01 and the two turn knobs in close vicinity are an absolute killer on top of the dial-wanking 2014-08-24 14:01 i suppose our experiences diverge there. i had (have) 2A+16D and find myself longing for 4A. i could imagine adding some D to the A, though, if they're nicely made. 2014-08-24 14:03 i expect the dial-wanking to go away as firmware improves. in a way, neither gets it quite right. the analysis mode of rigol is nice, but why not just merge segments and greyscale them ? then one could see a large bundle with each screen. 2014-08-24 14:05 umm, maybe I don't get it yet, but aiui each segment/frame has its own trigger and they are not supposed to be consecutive/gapless in time domain 2014-08-24 14:05 waveforms of siglent are okay in the ranges that most matter. in ones where it drops badly you're basically just magnifying the interpolation anyway 2014-08-24 14:06 correct 2014-08-24 14:06 nah, you got me wrong I guess 2014-08-24 14:06 lemme try to find the right timecode 2014-08-24 14:06 so i'd overlay frame #0 with frame #1, etc., through frame #n. each with trigger point at the same position. then divide brightness by n 2014-08-24 14:08 so "zoom" would not be on the time axis (though rigol seem to do that, which looks odd even if it may be convenient) but on the number of waveforms that make up one screen 2014-08-24 14:08 it's the same as intensity grading in normal operation: there you also have multiple waveforms visible at the same time 2014-08-24 14:10 https://www.youtube.com/watch?v=zOjLNyzxkTQ#t=4241 2014-08-24 14:14 1:14:33 2014-08-24 14:14 too 2014-08-24 14:15 yes. 1 ns/div. most of what you see there is interpolation. just do the math :) 2014-08-24 14:17 https://www.youtube.com/watch?feature=player_detailpage&v=zOjLNyzxkTQ#t=2123 aka 35:25 2014-08-24 14:18 yes, navigation is very poor there 2014-08-24 14:18 I'm not buying anything ever based on "hoping that they will fix this issue eventually" 2014-08-24 14:19 ;-) 2014-08-24 14:19 an open source scope would be great for that. there, you'd have certainty, not hope :) 2014-08-24 14:19 "it will be fixed. and if i have to do it myself." :) 2014-08-24 14:19 *maybe* when *I* could fix it 2014-08-24 14:19 exactly 2014-08-24 14:20 that's why I insist on comprehensive remote control option 2014-08-24 14:20 it *might* be possible to "fix" the siglent on that level 2014-08-24 14:21 39:00 2014-08-24 14:21 that's not the same. yes, you can work around some limitations, but there's a huge convenience penalty 2014-08-24 14:21 also a killer, and start of analysis mode I mentioned (iirc) 2014-08-24 14:22 well, let's see how siglent proceed with those things. i'm not buying a new scope these days anyway, so i have time :) 2014-08-24 14:23 waterfall mode in siglent is what you asked for above, no? 2014-08-24 14:24 40:50 2014-08-24 14:25 41:50 !! No analysis mode in siglent 2014-08-24 14:26 waterfall mode seems to have an offset, so it shows wave #0 at horizontal 0, wave #1 at -1 div, wave #2 at -2 div, etc. 2014-08-24 14:27 42:55 s/"minutes and minutes"/"hours and days"/ 2014-08-24 14:27 yes, overlay is the version without offset 2014-08-24 14:28 all the way up to 44:00 has a clear statement that siglent is useless for a dso, since the most important feature is flawed to oblivion 2014-08-24 14:29 no use in recording a 20mio points when you can't analyze/search them for that glitch you're looking for 2014-08-24 14:30 (overlay mode) yes, but the step size of 20 should be variable 2014-08-24 14:31 44:40 is about where it shows the difference between rigol and siglent regarding this 2014-08-24 14:31 (recording) you could proabably download them to a PC :) 2014-08-24 14:32 https://www.youtube.com/watch?feature=player_detailpage&v=zOjLNyzxkTQ#t=2781 2014-08-24 14:32 then I don't need all that sophisticated stuff in scope at all 2014-08-24 14:36 also the mere ergonomics of placing the menu softkeys above the 4 BNC for the probes is already giving my wrist aches from just watching this guy operating those 2014-08-24 14:39 FrankBlues has joined #qi-hardware 2014-08-24 14:39 50:38 :-S 2014-08-24 14:39 dunno. i have my scope on a shelf and the bncs are right under the main controls. not a problem. 2014-08-24 14:40 https://www.youtube.com/watch?feature=player_detailpage&v=zOjLNyzxkTQ#t=3038 2014-08-24 14:40 FrankBlues has quit [Client Quit] 2014-08-24 14:40 Frank_Blues has joined #qi-hardware 2014-08-24 14:41 Frank_Blues has quit [Remote host closed the connection] 2014-08-24 14:41 FrankBlues has joined #qi-hardware 2014-08-24 14:41 "I first have to *stop* the scope, then I can move around and manipulate the timebase..." 2014-08-24 14:42 no, we don't actually need to discuss siglent any longer 2014-08-24 14:43 rigol it is, MSO2102A 2014-08-24 14:44 siglent is a poor man's knockoff of rigol 2014-08-24 14:44 years behind in maturity, firmware and UX wise 2014-08-24 14:44 I don't need 4chan that are useless 2014-08-24 14:45 when for same money I can get 2chan that work the way they are supposed to 2014-08-24 14:55 yeah, siglent is kinda crap 2014-08-24 15:08 >>But most disappointing to me was the lack of any meaningful ability to navigate the huge sample sets that the unit is capable of capturing. Whether in Frame mode or History mode, it can collect more data than you could ever do anything useful with. Which is a real shame, since it basically negates a very powerful feature. It's bad enough that there is no quick access mechanism, just slow knob twiddling, but that's compounded by 2014-08-24 15:08 the inability to even vary the Playback speed. I wonder if Siglent is ready for the barrage of Carpal-Tunnel lawsuits that will follow. [And guys, I'm only half kidding!]<< http://www.eevblog.com/forum/testgear/review-siglent-sds2304-a-comparison-of-features-with-rigol-ds2000-series/msg500794/#msg500794 2014-08-24 15:09 seems i'm not the only one to already feel pain in his wrists while watching that video 2014-08-24 15:15 let's see how long it'll take them to fix it. that review should given them plenty of motivation ;-) 2014-08-24 15:20 i'd actually worry more about the two closely spaced knobs. that's much harder to solve. 2014-08-24 15:21 HAH!!! http://www.eevblog.com/forum/testgear/review-siglent-sds2304-a-comparison-of-features-with-rigol-ds2000-series/msg501116/#msg501116 2014-08-24 15:22 yes, as I already said that's the ultimative knock out criterion 2014-08-24 15:22 (buttons spaced to tight) 2014-08-24 15:23 (post) yeah, planting the idea of open source. you never know when and where it may bear fruits :) 2014-08-24 15:24 while it could get some stopgap fix by disabling the other (trigger) button during rotating the left one, to avoid "stealing focus", it still is a mech UI inconvenience that I don't see myself to get used to 2014-08-24 15:24 :-D @ FOSS 2014-08-24 15:25 (knob spacing) it does look like a bad flaw. well, maybe after a while you get used to it. for most usability problems it's hard to predict whether they will still bother you after a few weeks of regular use. sometimes even nasty stuff just "disappears". on the other hand, some annoyances annoy forever ... 2014-08-24 15:26 and it seems siglent hasn't even disclosed/published the SCPI(?) specs/docs 2014-08-24 15:27 so my approach for a fix by midi tablet would fail as well 2014-08-24 15:27 * DocScrutinizer05 afk, having a look if Nue changed 2014-08-24 15:28 also enjoying own shower, nothing better in the world really 2014-08-24 15:28 o/ 2014-08-24 15:28 they seem to be busy writing that document. they've already "pre-announced" to their distributors (who then of course post about it in eevblog :) 2014-08-24 15:29 what puzzles me is that i can't find the programming document for the sds1000 series. that one ought be be around and would provide clues of what the sds2000 will be able to do. 2014-08-24 15:30 of course, you have to be careful with such things. there are often weird little bugs and crippling misfeatures. also ran into such things in high-end scopes from tek and agilent. 2014-08-24 15:30 (high-end) the USD 10k+ type 2014-08-24 15:33 the only thing that can help on that is an agile responsive customer service 2014-08-24 15:33 alas this type of service is more likely to be found on very small companies, not on the expensive huge ones. Usually 2014-08-24 15:35 anyway thanks to today's discussion my idea about Rigol changed, till yesterday it had a certain russian army "takes sledgehammer to make it work" appeal to me 2014-08-24 15:35 that changed completely 2014-08-24 15:35 naw, rigol is a solid company. i think they started as makers of lower-end agilent, then began using their own brand 2014-08-24 15:36 now somehow siglent inherited that stigma 2014-08-24 15:37 yes, they're a few years behind rigol in profile development. they do look like the next chinese scope company to make it out of the "china crap" swamp, though. 2014-08-24 15:38 I wonder how reasonable it would be to speculate on hacks/cracks to enable features like enhanced triggering and stuff in a MSO2102A 2014-08-24 15:38 there's a thread on that, too ... ;-) 2014-08-24 15:38 yeah, but... 2014-08-24 15:39 a huuuge field to grok it all 2014-08-24 15:39 a bit ugly for the ds2000a series, though. like retrieve old fw, patch it, send it back. in the ds1000z it's just a code you have to enter. 2014-08-24 15:39 and i don't think they cracked the mso2000a yet. it's just a few weeks on the market. 2014-08-24 15:39 e.g. would a DS2102A be capable of MSO aka LA, just with a key to unlock? 2014-08-24 15:40 prolly not 2014-08-24 15:40 if it has the connectors, yes :) 2014-08-24 15:40 they even might be mechanically different 2014-08-24 15:40 but it seems that rigol are keeping the two apart 2014-08-24 15:41 unlike siglent, which seem to include MSO also in their DSOs. though without connectivity kit. so it's not entirely a software-only change. 2014-08-24 15:41 :nod: 2014-08-24 15:41 it also shows in the time: took rigol about 2 years to go from DS2000 (via DS2000A) to MSO2000A 2014-08-24 15:41 prolly it's also not really "fair" to buy a cheap model, hack it, then complain about stuff not working as expected 2014-08-24 15:42 siglent are now beginning to market the MSO capability, merely half a year after introducing the scope 2014-08-24 15:42 I wonder if a AWG is worth it 2014-08-24 15:43 prolly not, rather you'd want a LA-reversed 2014-08-24 15:43 one of my more stupid purchases was a function generator (with AWG and such). i hardly ever use it. 2014-08-24 15:43 so the thng could actually do tricks like "speak I2C" 2014-08-24 15:43 it can actually do LA-reversed, too. but then, so can, say, a Ben ... 2014-08-24 15:44 and the Ben can respond to what's coming back ... 2014-08-24 15:44 :nod: 2014-08-24 15:44 it would for sure need some *logic* for such trickery 2014-08-24 15:44 FrankBlues has quit [Quit: Leaving] 2014-08-24 15:44 not only braindead playback of a pattern 2014-08-24 15:45 meh! will ponder getting me a MSO2102A, while thought float during taking a shower 2014-08-24 15:45 bbl 2014-08-24 15:46 enjoy ! :) 2014-08-24 15:46 :-D 2014-08-24 15:46 sure will 2014-08-24 15:46 the standards in Spain are... not comparable 2014-08-24 15:47 e.g. I couldn't even figure how a 24kW water heater would get installed down there 2014-08-24 15:48 would prolly cause Barbate go blackout 2014-08-24 15:49 (j/k, not really. But actually electricity installations are kinda scary _still_) 2014-08-24 15:50 o/ 2014-08-24 15:50 maybe they use gas ? 2014-08-24 15:51 yup, they do 2014-08-24 15:52 but yes, in places with a warmer climate, heating equipment is often at a surprisingly poor level. e.g., you'll be much warmer in winter in switzerland than in argentina, even if the outside temperature is 15 deg lower in .ch 2014-08-24 15:53 heating water with gas works fine. i have one such critter. no complaints. and, unlike a boiler, you have an infinite reserve :) 2014-08-24 15:53 in a heater sized ~50*30*20 mounted tightly into a wooden kitchen cabinet of exactly same size :-o 2014-08-24 15:54 with door 2014-08-24 15:54 at least they left out the bottom to give the thing some air to breathe, from below 2014-08-24 15:55 25 x 40 x 75 cm here :) 2014-08-24 15:55 fed by a 20L propane bottle that sitts inder the kitchen sink 2014-08-24 15:55 yuck 2014-08-24 15:55 these are dangerous 2014-08-24 15:55 (50*30*20) the ones with the almost egg-shaped rounded corners 2014-08-24 15:56 the ignition flame always is "open", not bimetal safety device opening only while heated or pushbutton pressed - WAAAAH! Duck and cover! 2014-08-24 15:57 * DocScrutinizer05 wonders if such safety mechanisms are mandatory in Germany only 2014-08-24 15:58 (egg shaped) kinda like this one http://commons.wikimedia.org/wiki/File:Merker_Durchlauferhitzer.jpg 2014-08-24 15:58 the "pilot" flame is a standard feature in this type of device 2014-08-24 15:59 there are better ones with electric ignition but the gas-only type needs a pilot 2014-08-24 15:59 err wut? I'm talking about switching it off when it's already off. By sensing heat and stopping gas flow when no heat 2014-08-24 16:00 yes, then you'd need some sort of bypass valve 2014-08-24 16:00 we have that on virtually every gas flame no matter where, here 2014-08-24 16:00 bypass valve? 2014-08-24 16:01 to turn it on. it has to be able to automatically turn on. so if you cut the gas when it's cold, you need to bypass the cutoff to turn on 2014-08-24 16:02 btw, ovens are different. there, you just hold the button until the bimetal is hot enough 2014-08-24 16:02 usually those things work with a thermocouple that actually provides enough current to magnetize an e-magnet consisting of some 20 windings of 1.5mm dia copper wire, and you push the steel plate to the magnet maually by pushing a button and thus opening the valve. When thermocouple heats up, the steel plate sticks to magnet 2014-08-24 16:03 so that's an electric model. they can be more complex, yes. but we're talking about the basic gas-only ones, aren't we ? 2014-08-24 16:03 on water heaters it works exactly same way like oven, just for the pilot flame 2014-08-24 16:04 e.g., if electric, you don't need a pilot flame at all 2014-08-24 16:04 there's no electricity fed to that type of security device 2014-08-24 16:05 it consists of a thermocouple, a coaxial (dunno why) wire from couple to magnet, and the magnet coil. That's it 2014-08-24 16:05 the thermocouple seems capable to provide some maybe 0.2V@3A or whatever 2014-08-24 16:06 ooooh so THAT is how they work 2014-08-24 16:06 cool 2014-08-24 16:06 ah, i see 2014-08-24 16:08 https://www.danninger-shop.at/media/wysiwyg/sicherheit.jpg 2014-08-24 16:08 http://www.fluessiggas-center.de/zubehoer-und-ersatzteile/125/thermoelement-universal 2014-08-24 16:09 >>Abgebende Spannung 30 mV<< 2014-08-24 16:09 http://www.fluessiggas-center.de/zubehoer-und-ersatzteile/175/magneteinsatz-50-mbar 2014-08-24 16:10 >>erzeut der Thermofühler eine 40 mV Spannung und einen Strom von ca. 10 mA<< o.O 2014-08-24 16:12 (coaxial) maybe for safety reasons, so nothing could induce a current into it 2014-08-24 16:18 usually you press a pushbutton which moves the steel plate against the magnet and thus opens the pilot flame's (actually the whole device's) gas valve, and same time the pushed button closes a valve for main flame, defeating huge amounts of gas coming out the thing when pushing button while water flows and pilot flame not burning 2014-08-24 16:19 then you ignite the pilot flame and wait until it heated the thermocouple, before you release the pushbutton and thus the device enters "normal operation mode" 2014-08-24 16:19 no such pushbutton on the spanish water heater 2014-08-24 16:20 which I guess is highly illegal even for Spain 2014-08-24 16:34 I mean you don't want the gas even for pilot flame coming out of device for hours or days, right? 2014-08-24 17:23 astr has quit [Ping timeout: 240 seconds] 2014-08-24 17:29 rz2k has quit [] 2014-08-24 17:36 astr has joined #qi-hardware 2014-08-24 17:52 Hi larsc, you there ? 2014-08-24 18:00 larsc, how many MSPS can the FM-Comms 4/5 push? 2014-08-24 18:18 54MHz is the analog bandwidth limit 2014-08-24 18:19 the digital interface can do more 2014-08-24 18:19 but there is really no point 2014-08-24 18:20 FMCOMMS4 is one I/Q channel, FMCOMMS5 is 4 I/Q channels 2014-08-24 18:36 so 54 MSPS for 4*2 channels in parallel? 2014-08-24 18:37 yes, on each channel 2014-08-24 18:37 so 54*4*2*2 bytes/second 2014-08-24 18:39 that's not much :p 2014-08-24 18:39 I think it is 56MHz actually 2014-08-24 18:42 so that would be around 864 MiB/s max 2014-08-24 18:44 MB/s 2014-08-24 18:50 ok, thanks 2014-08-24 18:51 larsc: I'm modifying dma-jz4740.c to make it work with jz4770 2014-08-24 18:51 2014-08-24 18:51 since there is no device tree support for jz4740, what's the best way to know which of jz4740 or jz4770 is using the dma-jz4740.c driver ? 2014-08-24 18:51 use an ID; see our watchdog driver 2014-08-24 18:52 I thought about using a platform_devic_id struct indeed, and came up with something like this: http://paste.debian.net/117277/ 2014-08-24 18:52 kilae has quit [Quit: ChatZilla 0.9.90.1 [Firefox 31.0/20140716183446]] 2014-08-24 18:54 pcercuei: ah, same trick is used in watchdog driver, would have save me some trouble if I knew :-) 2014-08-24 18:54 yes, that's the way to go 2014-08-24 18:57 pcercuei larsc: ok, thanks 2014-08-24 20:04 wej_ has quit [Ping timeout: 250 seconds] 2014-08-24 20:06 wej has joined #qi-hardware 2014-08-24 20:10 wej has quit [Ping timeout: 250 seconds] 2014-08-24 20:12 wej has joined #qi-hardware 2014-08-24 20:49 jekhor has joined #qi-hardware 2014-08-24 22:27 wolfspraul has quit [Quit: leaving] 2014-08-24 22:31 dandon has quit [Remote host closed the connection] 2014-08-24 22:32 jekhor has quit [Ping timeout: 240 seconds] 2014-08-24 22:38 dandon has joined #qi-hardware