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[01:30:33] <carabia> kre10s_: you _might_ want a pullup on chip select, tops
[01:31:07] <carabia> the rest doesn't really matter cause they ought to be in known states when you're actually driving the bus
[01:45:52] <rue_bed> anyone here written a colour meter?
[01:50:59] <carabia> oh and yeah. pullup/down depends on which way the cs works, obv.
[01:51:11] <carabia> not all are active-low
[03:59:31] <WormFood> rue_bed, what is a "colour meter"?
[04:01:04] <Jartza> WormFood: I don't know either, but you just wrote it! :)
[04:01:10] <Jartza> colour meter
[04:01:14] <Jartza> now I've written it too
[04:01:53] <WormFood> a "color meter" could be many different things. I'm just trying to clarify what exactly he is asking about.
[04:12:52] <Jartza> well he asked if anyone has written it :)
[04:18:20] <WormFood> has written what?
[04:19:37] <WormFood> A color meter that measures what? colors obviously...but the color of what? Light? A solid object?
[04:20:32] <cehteh> possibly these monitor calibration things
[04:20:50] <WormFood> possibly.
[04:21:11] <WormFood> I haven't seen those in person, but I'm aware of their existence
[04:21:29] <cehteh> https://en.wikipedia.org/wiki/Tristimulus_colorimeter
[04:31:44] <skz81> Jartza, your humour is too subtle, it seems :)
[04:32:45] <skz81> WormFood, isn't the color of an object the color of the light it reflects/emits ?
[04:33:13] <WormFood> no
[04:33:20] <WormFood> it's an inverse of what it reflects.
[04:33:33] <WormFood> it absorbs all other colors of light, and reflect the color you see
[04:33:54] <WormFood> So, a red apple, really isn't red. It's everything except red. Make sense?
[04:34:12] <liwakura> no
[04:34:44] <liwakura> i would apply "the color it is" to the stuff reflected
[04:34:48] <skz81> I call the appel, red, not "everything but red"
[04:34:55] <skz81> apple*
[04:35:06] <WormFood> of course we call it red, because that is what it looks like to us.
[04:35:22] <WormFood> I'm talking about on the technical level, of what is really happening.
[04:35:25] <liwakura> actually, color is not even an intrisical property
[04:35:47] <skz81> hmmm wavelength is, and it's related
[04:35:49] <liwakura> so actually, object cant have colors
[04:36:18] <liwakura> color is sorta what we observe what gets reflected when we put light onto it
[04:36:25] <WormFood> banknotes and real money spend the same, but how many people make that distinction when talking about it? Nobody, because they look and act the same, even tho they're polar opposites.
[04:36:30] <liwakura> put green light, and a red apple appears black
[04:37:05] <WormFood> color and light is an interesting subject.
[04:37:29] <liwakura> my room is sorta special, because it looks really party-like and wild and rebellious for RGB people
[04:37:43] <liwakura> but for GB people its sorta gothic-like
[04:37:48] <liwakura> because much red
[05:30:45] <Jartza> skz81: yeah, humour is diffucult genre :)
[09:17:33] <rue_house> WormFood, well, I'm prolly gonna go with an RGB led and a photoresistor, it'll loook at, what will probabbly be a marble, and give me r, g, b values for it
[09:18:19] <liwakura> photodiodes might be more useful for identifying certain wavelength
[09:18:55] <rue_house> I'm planning to have it pre-calibrate
[09:19:02] <rue_house> for the sensor differnce
[09:19:37] <rue_house> I was interested if anyone has ever done it before
[09:27:10] <bss36504> Don't hate me, but why not just use a color sensor?
[11:24:23] <WormFood> When did the letter for voltage in formulas, change from E to V? I thought "V" was only used by retards, who didn't know electronics. Now a majority of what I see uses V.
[11:26:35] <cehteh> E? it is U
[11:28:51] <aandrew> I use V
[11:29:02] <aandrew> I don't like using E but I kind of transparently "translate" it in myh head
[11:32:21] <cehteh> the english term 'voltage' is already misleading as it implies the measurement unit, for ampere its 'current' and in german we have 'Spannung' (which translates to 'Tension') for voltage
[11:32:41] <WormFood> well, "I" is for "Intensity", in amps
[11:32:53] <WormFood> E is for Electromotive force, measured in volts.
[11:33:22] <WormFood> R is for Resistance, and P is for Power, measured in watts
[11:33:30] <cehteh> didnt know that 'I' stands for intensity, i suspected some latin term
[11:33:35] <cehteh> well makes sense
[11:34:05] <WormFood> Did you ever wonder why the abbreviation for pound and ounce is lb and oz? There is no l or b in pound, and no z in ounce.
[11:34:30] <cehteh> no i am in metric land .. never cared about imperial that much
[11:34:52] <WormFood> me too, but I'm not ignorant.
[11:35:11] <WormFood> I can use any system. It ain't nothing but a thang.
[11:35:24] <cehteh> lb also stands for 'stones' .. but still no L or B ... or?
[11:35:37] <WormFood> it does not stand for stone
[11:35:41] <cehteh> ok
[11:35:48] <WormFood> lb and oz are italian
[11:35:59] <cehteh> well imperial/english measurement units are confusing
[11:36:03] <WormFood> I forget why English uses those abbreviations tho, but they're from Latin.
[11:36:08] <WormFood> Confusing?
[11:36:16] <WormFood> So, math is confusing for you too? :P
[11:36:21] <cehteh> yes
[11:36:36] <WormFood> most things are based on 12, or a unit of 12
[11:37:13] <WormFood> I can understand where 4 cups in a pint, and 4 pints in quart, and 4 quarts in a gallon, could get confusing.
[11:37:24] <skz81> Did use E, only for (continuous) sources IIRC. Other tension in the circuit can be named freely U, V etc...
[11:37:35] <WormFood> Actually, I think one of those is off, not 4, but really 2
[11:38:03] <WormFood> base 12 makes sense.
[11:38:16] <skz81> <WormFood> Did you ever wonder why the abbreviation for pound and ounce is lb and oz? There is no l or b in pound, and no z in ounce. >> LiBra in latin
[11:38:37] <WormFood> skz81, it's Italian, which is based on latin.
[11:38:50] <WormFood> so, technically, that's correct.
[11:39:40] <skz81> Ho, maybe you're right about italian, though
[11:40:33] <WormFood> I'm 1/4 Italian. ;) That's why it stuck in my memory
[11:41:10] <WormFood> But, if we didn't use "lb" and "oz", what would we use?
[11:41:35] <skz81> grams !
[11:42:05] <skz81> Just found out libra comes from greek "Litra" that also gave "Litre"
[11:42:21] <skz81> liter*
[13:14:46] <jacekowski> WormFood: the letter for voltage was always U
[13:14:59] <jacekowski> WormFood: unless you are in english speaking country then it becomes V
[13:41:44] <WormFood> jacekowski, a quick googling would tell you that is a false statement.
[13:42:26] <WormFood> In college and high school, it was *ALWAYS* E. I have ohm's law, using E for voltage, burned into my brain.
[13:58:06] <twnqx> E?
[13:58:13] <twnqx> never even heard of that
[13:58:42] <twnqx> not in school, not in university, not in any book
[13:59:06] <twnqx> might be an american thing
[14:56:37] <carabia> wtf is this nonsense.
[14:56:38] <carabia> E = EMF
[15:12:07] <carabia> You can't clock 32u4 to 16 MHz at 3.3 V reliably, no?
[15:13:08] <bss36504> Are you asking because you know it's outside the datasheet specs or have you just not seen them?
[15:14:52] <carabia> I know it's outside the datasheet. And yeah I know you can test many an individual and choose _some_ that work. But I'm asking whether someone over here has done any testing on this
[15:15:06] <carabia> I remember someone picked up a bunch of 32u4's and was playing around with them
[15:15:52] <bss36504> Oh I gotcha. I mean, if it's not wildly outside the spec it might be ok. But I certainly wouldnt do it for something "mission critical"
[15:18:06] <DKordic`> carabia: IIRC XMEGA can go upto 32MHz on 3.3V.
[15:18:54] <bss36504> I think someone got an XMEGA to 80Mhz on 5V once
[15:19:10] <bss36504> Making it work is one thing, making it work reliably is another.
[15:19:58] <carabia> DKordic`: yeeeah. xmega just gets a bad rap. I could just skip avr32 + xmega altogether and go for a cortex-m0
[15:20:35] <carabia> last time i played with them though i was severely ass-hurt by the fact how complicated it is to actually set the peripherals up
[15:21:50] <carabia> and last time i was perusing stuff for xmega the support seemed really lackluster. I wonder why they haven't killed that line already
[15:22:01] <bss36504> Haha seriously.
[15:22:10] <carabia> seriously what?
[15:22:17] <bss36504> The Xmegas are what the mega should have been but too late
[15:22:22] <bss36504> oh, seriously about the peripheral setup
[15:22:28] <bss36504> on the M0
[15:22:36] <carabia> yeap
[15:23:52] <bss36504> I love 8-bits for a lot of things, but I think the growing industry consensus is why use an 8 bit and require your embedded guy to specifically know that platform, when you can buy a faster m0+ for the same amount of money and everyone and their brother knows how to code for ARM (and there is existing code for it)
[15:25:04] <carabia> that's true too. But it really depends on the application
[15:25:22] <carabia> you don't need, and often don't even want an arm for simple solutions
[15:27:52] <DKordic`> bss36504: I can't beleive 8051 (68HC11) is still alive.
[15:29:16] <bss36504> No, I agree. There is a time and a place for 8-bit, but I think those times are less frequent and those places are dwindling under the shadow of ARMatron.
[15:29:49] <bss36504> 8051 is crap and should not be used. I cringe everytime I see some stupid chinese gadget with a 48Mhz 8051. Why must you do that :(
[15:30:31] <DKordic`> :D
[15:33:58] <Tom_itx> was the 8051 the same instruction set as the 68hc11?
[15:34:52] <twnqx> it's also kinda annoying if an arm with several times the power has the same (or lesser!) price tag as 8bit avrs :/
[15:35:13] <Tom_itx> larger learning curve too
[15:36:34] <Tom_itx> although i enjoyed the 68332 and it has like 9 or so books that come with it
[15:44:26] <Jartza> evening
[15:58:54] <WormFood> carabia, that's what I said. E=EMF. I have no idea when "V" became popular.
[15:59:29] <WormFood> twnqx, when were you in school? This might be a relatively recent change.
[17:01:43] <WormFood> If my 3.3 volt powered AVR, somehow had 12 volts applied to it's ADC input, would it be possible to burn out, just that one adc input, and not harm any other functions of the chip? (I'm just looking for possible explanations, as to why my ADC appears to have quit working.)
[17:04:15] <LeoNerd> It coudl well do. Even if powered at 5V surely
[17:04:19] <LeoNerd> Those clamp diodes
[17:05:27] <WormFood> Usually, if something is a problem like that, it would cause problems somewhere else.
[17:06:01] <WormFood> if this ADC quit working, then I'll just live with it. I'm not gonna rewire it to use a different input, because I expect to have a new design on a real PCB "real soon" ;)
[17:07:38] <twnqx> WormFood: i left school '94...
[17:15:17] <WormFood> twnqx, '88 for me
[18:10:43] <Casper> WormFood: avr have diodes from all pin to vcc and gnd
[18:10:57] <Casper> so sending 12V to the ADC may power everything at 12V
[18:12:45] <Tom_itx> sounds rather terminal to me
[18:32:53] <Casper> yeah
[18:50:40] <mrx1_> are there any integrated circuits, which could read data to itself, like DMA reads data to ram? and than at later time this data would be accessible by SPI
[18:51:45] <mrx1_> (because i need to sample about 50 ms of 2 MHz signal and store it for later processing, and 8bit avr won't do it)
[19:00:38] <twnqx> mrx1_: i've seen people use SPI RAMs to build logic analyzers with exactly that isea
[19:00:51] <twnqx> as long as clock runs, they will read bits into them
[19:02:08] <mrx1_> but without MCU? what will make sure that values are put in proper places in such RAM
[19:02:22] <twnqx> well, you need an mcu initially
[19:02:35] <mrx1_> and if mcu has to process each sample, avr will be to slow
[19:02:43] <twnqx> no need for that
[19:02:50] <mrx1_> twnqx: could you describe how this works ?
[19:02:54] <twnqx> mcu writes the command, tristates the data out
[19:03:12] <twnqx> keeps clock running, on each clock spi ram thinks" oh, a bit written me"
[19:05:33] <twnqx> http://dangerousprototypes.com/docs/Logic_Shrimp_logic_analyzer this i think it was, or something similar
[19:06:18] <mrx1_> twnqx: ok, thank you very much, i will read about this
[19:06:38] <twnqx> and i'll head to bed. jeez, 2am again...
[19:27:07] <Mr_Sheesh> WormFood, ugh that sounds bad. Maybe a series R and a zener cross the ADC pin to ground woukd be wise, size R so the zener won't blow at the max current etc., per usual, but ofc then your adn pin gets a low pass RC filter on its input - which could mess up your data potentially. (z transforms could be used to correct the data but ugh :p)
[19:27:42] <Mr_Sheesh> typos -rolls eyes- would* adc*
[19:32:19] <WormFood> Mr_Sheesh, do you think that is likely to happen, under that circumstance?
[19:33:07] <WormFood> I've had AVRs plugged in backwards, for 5 minutes. It was hotter than hell, but still worked when plugged in the correct way.
[19:33:36] <WormFood> I don't know if that is what happened. I doubt the ADC input was shorted to +12V
[19:33:47] <WormFood> I was just wondering... ;)
[20:15:13] * ThatDamnRanga just got a puzzling, slightly disturbing email'
[20:15:23] <ThatDamnRanga> so MicroChip has acquired Atmel
[20:17:08] <ThatDamnRanga> I'm sure I'm late to the party, but ....
http://www.microchip.com/docs/default-source/announcements-documents/atmel-customer-letter-april-2016.pdf?utm_campaign=May_2016_eNewsletter_A&utm_medium=email&utm_source=Eloqua
[20:18:02] <Lambda_Aurigae> months late
[20:18:18] <Lambda_Aurigae> but, yeah, I got the email from atmel today too.
[20:18:46] <ThatDamnRanga> so long as Atmel's kit is the stuff that wins out, I'm okay
[20:18:56] <ThatDamnRanga> because it's far better than the PIC stuff :P
[20:19:23] <Lambda_Aurigae> I hope I can get atmel samples like I can get microchip samples!
[20:19:37] <Lambda_Aurigae> each platform has its strengths and weaknesses.
[20:19:43] <Lambda_Aurigae> I like pic for the 32bit line.
[20:20:20] <Lambda_Aurigae> and I hope they go with atmel's open platform for the compilers.
[20:20:24] <Lambda_Aurigae> but I doubt it will happen.