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[02:20:47] <eldift> test test
[03:44:46] <RLa> eeprom is zeroed out on new chips?
[04:07:28] <bitd> Actually I think its 1
[05:37:08] <Lambda_Aurigae> RLa, eeprom, like flash, is erased to all ones. With one exception in the AVR
[05:37:28] <Lambda_Aurigae> that exception being the calibration bytes for the onboard RC oscillator.
[05:40:36] <RLa> thanks
[05:40:43] <Lambda_Aurigae> welcome.
[08:56:50] * LeoNerd ponders design for a 4-at-once continuity tester
[08:57:32] <LeoNerd> Namely: 1 probe, 4 clip leads... 1 multicolour LED that indicates continuity between probe and any of the clip leads, simultaneously. Planning to use it for board verification - put clip leads on power + ground planes and two big signals, trace lots at once
[10:48:02] <Lambda_Aurigae> LeoNerd, sounds like a logic analyzer to me.
[10:48:09] <Lambda_Aurigae> http://i.imgur.com/DPY3MRC.jpg
[10:58:00] <LeoNerd> Lambda_Aurigae: Nope, it's a cont. tester. It's for unpowered boards, just to trace where the copper goes
[10:58:26] <Lambda_Aurigae> so a logic analyzer with it's own logic signal!
[10:58:54] <LeoNerd> Ooh.. hrm. I suppose that could be an easier way to build it, yes
[10:59:59] <LeoNerd> At some point though I do want to make one that'll work on "live" boards as well
[11:03:16] <LeoNerd> I keep wondering if I can find a way to distinguish "this is a driven output at logic high/low" from "this is connected directly to a power rail", but I'm not sure if there is
[11:03:39] <Lambda_Aurigae> slight voltage difference.
[11:03:58] <LeoNerd> Hmmmm.. that could work
[11:12:20] <twnqx> just pull to gnd
[11:12:30] <twnqx> if a chip smokes, it was a signal
[11:12:41] <twnqx> if the whole things goes out, it was vcc :3
[11:12:54] <LeoNerd> Yeeees.... well that's -a- way but I feel perhaps not the most useful
[11:13:51] <twnqx> i wondered the same though actually
[11:13:59] <twnqx> and my conclusion was the same as Lambda_Aurigae's
[11:14:33] <twnqx> pull down/up via a resistor (1M or so) and mesaure the change in voltage
[11:15:40] <LeoNerd> Ooooh that could be good, yes
[11:16:30] <twnqx> obviously, drive an opamp with a high input resistance
[11:16:40] <twnqx> and not straight into an AD
[11:16:43] <twnqx> A/D*
[11:16:43] <LeoNerd> Quite
[11:17:30] <twnqx> and if you have no idea about the source voltages, use clamp diodes :P
[11:18:05] <LeoNerd> Well, the thing itself will be attached to the supply rails, so if it has more than +5V I should say "er, nope. not touching that"
[11:18:40] <twnqx> i would probably use an opamp with +-15V do have enough headroom to go up to 12V
[11:18:52] <twnqx> to*
[11:19:40] <twnqx> then scale down & shift up
[11:20:36] <twnqx> so 30V input dynamic range, divide by ten -> 3V range for ADC (but +-1.5) and then add another 1.5 so 0-3V, shich should fit a dedicated op amp
[11:20:47] <twnqx> with 1M the voltage drop should be pretty low though :P
[11:42:38] <awaq> hi
[11:43:00] <awaq> does anyone have experience with arm stm32f4 cortex m4 chips?
[11:43:29] <Lambda_Aurigae> not I.
[11:43:35] <Lambda_Aurigae> you might try in an arm channel.
[11:43:43] <awaq> there is nobody online
[11:43:52] <awaq> or i dont know any channel for arm
[11:44:03] <Lambda_Aurigae> not a lot here at the moment either.
[11:44:08] <specing> awaq: #stm32 does
[11:44:24] <awaq> thanks
[11:44:25] <specing> awaq: learn to use alis for the next time
[11:44:32] <awaq> alis?
[11:44:37] <specing> /msg alis help
[11:44:44] <Lambda_Aurigae> so, alis is a bot.
[11:44:56] <specing> Advanced LIsting Services
[11:45:01] <Lambda_Aurigae> a bot.
[11:45:14] <specing> a service bot.
[11:45:19] <awaq> didnt know her yet, thanks
[11:45:35] <awaq> hmpf nobody answers at #stm32
[11:46:27] <Lambda_Aurigae> sometimes you have to wait a while.
[11:46:32] <Lambda_Aurigae> minutes, hours, even days.
[11:46:40] <Lambda_Aurigae> irc isn't texting.
[11:46:46] <LeoNerd> If nobody's around, nobody will mind you loitering in channel waiting for an answer, also :)
[11:46:47] <Lambda_Aurigae> give it some time.
[11:46:55] <LeoNerd> I really hate people who turn up, ask a question, then leave after 2 minutes of silence
[11:47:10] <Lambda_Aurigae> LeoNerd, they wait two whole minutes?!?!
[11:47:19] <LeoNerd> Also it's a Sunday afternoon - maybe some folks are offline for the weekend, and will be more active on Monday
[11:47:56] <Lambda_Aurigae> them darn victims of christ and their churches interfering with us getting the answers we so deserve!
[11:48:09] <awaq> yeah ok but i think if im on an irc i can be online and must not bum around there
[11:48:33] <Lambda_Aurigae> I hang out in channels all the time and just watch.
[11:48:46] <LeoNerd> It's quite acceptable to loiter in an IRC channel. that's what it's for
[11:49:51] <specing> once I waited 3 weeks for an answer
[11:51:08] <awaq> wow 3 weeks, there i can take a course at the university and learn more about :D
[11:52:12] <awaq> mabe someone can answer my question: waht is the max fcpu of a stm32f407? at st.com they write 168MHZ, is it the maximum? how can it reach it? need i an expernal osc/crystal?
[11:52:30] <Lambda_Aurigae> look in the datasheet.
[11:52:35] <specing> no, you can overclock it
[11:52:42] <Lambda_Aurigae> and, yes, you will need an external clock and/or crystal most likely.
[11:57:46] <awaq> 168MHz crystal?
[11:57:56] <Lambda_Aurigae> oscillator.
[11:57:59] <Lambda_Aurigae> clock source.
[11:58:06] <Lambda_Aurigae> using a crystal and pll and such stuff.
[11:58:33] <Lambda_Aurigae> or, perhaps it takes a 20MHz or some such crystal and has internal PLL
[12:00:28] <awaq> ok, and i can overclock it? how much?
[12:00:41] <Lambda_Aurigae> well, look in the datasheet.
[12:01:01] <awaq> dont know where i should look
[12:01:22] <Lambda_Aurigae> although, overclocking usually isn't in datasheets....more like the max operating specifications.
[12:01:43] <Lambda_Aurigae> you might try looking in the clock section.
[12:01:48] <Lambda_Aurigae> or, maybe, just read the dang thing.
[12:03:18] <Lambda_Aurigae> would be a better question for #stm32 ultimately. You might have to actually wait for an answer.
[12:04:20] <Tom_itx> aww
[12:04:25] <Tom_itx> but i don't wanna wait...
[12:04:42] <awaq> ok thanks, im away now, bye
[12:06:34] <Lambda_Aurigae> damned germans,,,
[12:07:59] <Lambda_Aurigae> always impatient to conquer the world without reading the manual first.
[15:40:02] <aer93> hi, I'm quite noob. Does anybody know whats the point of having more than one UART in the same board? I'm programing with the atmega2560 and I have 4!, I'm using one, whats the point of the other three ?
[15:56:44] <Lambda_Aurigae> aer93, well, for talking with multiple devices over uart for starters.
[15:57:08] <Lambda_Aurigae> aer93, you don't necessarily have to use them all. You can use the pins as GPIO instead.
[15:57:32] <aer93> but I only have one usb port
[15:57:37] <aer93> how could I use the others?
[15:57:57] <Lambda_Aurigae> the atmega2560 doesn't have a usb port.
[15:58:03] <aer93> ahhhh
[15:58:05] <aer93> ok
[15:58:16] <aer93> i'm thinkn in my arduino board jejje
[15:58:17] <Lambda_Aurigae> I'm guessing you have a usb to serial adapter chip on there somewhere.
[15:58:19] <aer93> ok, now I get it
[15:58:20] <Lambda_Aurigae> oh.
[15:58:23] <Lambda_Aurigae> ardweeny.
[15:58:31] <Lambda_Aurigae> so the usb to serial adapter is connected to one usart.
[15:58:34] <aer93> i could have many but my board has only one
[15:59:23] <Lambda_Aurigae> the atmega2560 has 4 usarts. You can use the other three to communicate with other AVR chips or with other devices that have usarts.
[15:59:58] <aer93> I see, thank you very much
[16:00:14] <aer93> I'm really starting with this as you can see hehehe
[16:01:12] <aer93> I'm was using my arduino mega, that has as you say one usb to serial adapter chip, so I was confused why did I have 3 usart, but now its clear.
[16:01:55] <Lambda_Aurigae> unfortunately I can not help you with ardweeny specifics as I have never used the arduino software or layouts.
[16:02:42] <Lambda_Aurigae> I started with AVR before arduino existed and never saw the need for the arduino abstractions.
[16:05:04] <aer93> ok, no problem, you have cleared me so many things with that simple observation.
[16:11:16] <Casper> aer93: you could have 1 pc interface, 1 gps module, 1 cellular module and a debug interface
[17:00:51] <aer93> mmm, does anybody know where the avr-libc are located in ubuntu or how could I find them ?
[17:01:19] <LeoNerd> No idea on ubuntu but on straight debian it's just called avr-libc
[17:05:59] <Lambda_Aurigae> aer93, /usr/lib/avr
[17:06:33] <Lambda_Aurigae> unless it is part of the arduino software, in which case, no clue.
[17:56:36] <Lambda_Aurigae> 8 assassins against MacGyver and his Grandpa...odds don't look good.
[17:56:44] <Lambda_Aurigae> they should have brought a lot more assassins.
[18:00:08] <rue_more> anyone here ever made an i2c slave device with a tiny26?
[18:03:33] <Lambda_Aurigae> never had an attiny26 to play with here.
[20:54:11] <rue_more> they are the cheapest multichannel adcs
[20:54:25] <rue_more> you cant get an 11 channel 10 bit muxing adc for less than a tiny26
[21:13:20] <tpw_rules> what's the smallest micro i can use to host a USB keyboard or mouse? (not simultaneously)
[21:13:30] <tpw_rules> it seems v-usb can't do it which is rather annoying
[21:14:06] <N1njVacation> I would go with a ATMEGA32U2 - very easy to use.
[21:14:17] <N1njVacation> Alternatively you can do bit-bang USB, but that's pretty eh.
[21:14:33] <tpw_rules> if someone has source then sure
[21:14:39] <tpw_rules> i know v-usb can't be a host
[21:15:20] <Tom_itx> atmel only has 1 host 8bit avr i know of
[21:15:23] <Tom_itx> 1287 iirc
[21:15:27] <Tom_itx> mega1287
[21:15:31] <Tom_itx> otg
[21:16:05] <Tom_itx> you don't really need a host then the 32U2 is it
[21:16:15] <Tom_itx> 8U2 would probably be too small
[21:16:53] <tpw_rules> blah, i don't need one that powerful and i can't
[21:16:55] <N1njaneer> tpw_rules: Check out the LUFA code bade
[21:16:56] <tpw_rules> use a non dip
[21:17:03] <N1njaneer> +base
[21:17:38] <N1njaneer> tpw_rules: Then get an adapter board breakout, or one of the boards that host the entire thing on it, and break out to DIP
[21:19:38] <tpw_rules> doesn't lufa still require the hardware though? if i can get away with it for usb, one of the 8 pin micros is all i need
[21:20:24] <N1njaneer> I do not belive LUFA supports bit-bang USB.
[21:21:57] <N1njaneer> Tom_itx: Seen Dean lately, perchance?
[21:22:08] <Tom_itx> no not for a while
[21:22:20] <Tom_itx> lufa isn't bitbanged
[21:22:24] <Tom_itx> it's hardware usb
[22:36:23] <tpw_rules> is there a simple guide to setting up avr-gcc to do assembly as opposed to C? i need the speed for interrupts
[22:37:26] <tpw_rules> ah duh, just as a .S
[22:38:03] <N1njaneer> I would probably just put it in as inline assembler.
[22:38:15] <tpw_rules> that looks really disgusting to me
[22:38:31] <N1njaneer> Whatever works for you :)
[22:39:14] <tpw_rules> i'm thinking of an attinyX5. can all pins have interrupts? i need at least two
[22:44:41] <N1njaneer> Not sure on that part specifically, but most AVR series parts generally allow you to do pin-change interrupts on pretty much every pin that can be used as GPIO. Double-check the datasheet to verify. :)
[22:45:37] <tpw_rules> yeah it looks like it. i thought it usually only applied to one port
[22:46:37] <N1njaneer> Depends on the part. :)
[22:46:43] <N1njaneer> Okay, time for home. Gnight all!
[22:46:58] <N1njaneer> Jury Duty this week. How fun.
[22:47:33] <tpw_rules> just tell them you've read the constitution
