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[01:07:14] <mischief> has anyone ever used lex or yacc on an avr
[06:55:24] <Fleck> so guys, need idea to control PC fan with PWM from avr, controling is good, but there is a noise from fan on low speeds, I need some filtering...
[06:56:08] <Lambda_Aurigae> the fan isn't meant to run like that..you are likely hitting some resonance in the mechanism or coils.
[06:56:29] <Fleck> I know
[06:56:41] <Fleck> so I need custom DAC, simple...
[06:56:54] <Lambda_Aurigae> r2r dac is a wonderful thing.
[06:57:04] <Lambda_Aurigae> or a mosfet and a digital pot.
[06:57:19] <Fleck> r2r?
[06:57:25] <Fleck> road 2 ride? :D
[06:57:32] <Fleck> ready 2 ride?
[06:57:40] <Lambda_Aurigae> http://en.wikipedia.org/wiki/Resistor_ladder
[06:57:48] <Lambda_Aurigae> should be R-2R
[06:57:49] <Lambda_Aurigae> but,,
[06:58:02] <Lambda_Aurigae> a way of making a DAC with a bunch of the same value resistors.
[06:58:31] <Fleck> ha, no, I have one pin :D
[06:59:17] <Lambda_Aurigae> pwm to an opamp and some capacitor storage setup then?
[06:59:34] <Fleck> ok, schematics?
[06:59:42] <Lambda_Aurigae> use your imagination.
[06:59:49] <Lambda_Aurigae> that's what I would have to do.
[07:00:26] <Fleck> I am not you! :D
[07:00:35] <Fleck> my knowledge is not so great! :D
[07:00:51] <Lambda_Aurigae> just put a good size cap between the pins on the fan...470uF maybe? or 4700uF?
[07:00:58] <Lambda_Aurigae> play, experiment, try things.
[07:01:18] <Lambda_Aurigae> that's how I got what knowledge I have.
[07:03:09] <Fleck> cool but I don't want to invent new wheel :D
[07:03:20] <Lambda_Aurigae> play, try, and learn.
[07:03:32] <Lambda_Aurigae> you are already reinventing the wheel if you are making a fan controller.
[07:03:45] <Lambda_Aurigae> a plethora of them exist already.
[07:05:07] <Fleck> share some ;)
[07:05:49] <Fleck> but then again - availability is an issue
[07:05:58] <Tom_itx> http://component.iiic.cc/index.php?main_page=product_info&products_id=2524267&gclid=CjgKEAjwwPabBRCXo46OtM_RhGMSJACgCeqAOXqyR8qgmvc8JFqAIhreNg0jnv_yc-6xAJgUnV_4PPD_BwE
[07:06:53] <Tom_itx> http://www.maximintegrated.com/app-notes/index.mvp/id/1784
[07:08:08] <Fleck> see Lambda_Aurigae, I am not inventing the wheel :D
[07:08:17] <Fleck> thx Tom_itx
[07:08:19] <Tom_itx> http://www.ti.com/general/docs/lit/getliterature.tsp?literatureNumber=sbas386c
[07:09:11] <Tom_itx> http://www.linear.com/product/LTC1840
[07:09:40] <Tom_itx> http://www.analog.com/library/analogdialogue/archives/38-02/fan_speed.html
[07:09:50] <Tom_itx> probably every chip mfg has one
[07:10:44] <Tom_itx> but go ahead... make it harder than it needs to be.
[07:15:14] <Fleck> motherboards seems to use opamps
[07:29:34] <Tom_itx> oh and just in todays email:
http://www.mouser.com/new/NXP-Semiconductors/nxp-lpc1500-series/?utm_medium=email&utm_source=may2014&utm_campaign=cm-nxp-lpc1500-mpost&utm_content=lm
[07:29:44] <Tom_itx> a bit overkill for a fan
[07:31:22] <Fleck> :D
[13:52:17] <trackk> hello
[13:52:28] <trackk> how come so many people and nobody said anything for the last hour?
[14:03:42] <_Getty> thats normal, its IRC
[14:03:43] <umquant> Their answer will probably be "because hello isn't a question" lol
[14:04:02] <umquant> Can we help you with something?
[14:04:03] * _Getty throws some chips in the room
[14:04:08] <_Getty> see that bring some talk on ;-)
[14:09:58] <trackk> haha
[14:10:00] <trackk> thanks guys
[14:10:30] <trackk> i'm actually on the design of a new project
[14:10:51] <trackk> and I saw that atmel has those xmega class B specific for LCD displays
[14:11:47] <trackk> I was thinking on just getting a good ATxmega128A1U and use it as the main processor, also for controlling the display (which still don't know if LCD or OLED)
[14:11:52] <myself> _Getty: potato chips or silicon chips?
[14:11:57] <trackk> am I too crazy? haha
[14:12:19] <_Getty> i am _Getty? irgs...
[14:12:34] <myself> well if it's OLED, the LCD-specific chip ain't gonna do you much good, eh?
[14:12:44] <Getty> myself: of course silicon chips
[14:13:00] <Getty> myself: all attached with documentation and sample hex files on usb stick
[14:13:06] * Getty makes you a dream land
[14:13:19] <Getty> myself: are you feeling it? just close your eyes
[14:13:25] * myself floats above his chair
[14:13:39] <Getty> i told you not to take out of this box....
[14:14:02] * myself saves a .hex file to the usb-mass-storage enumeration and observes that the chip boots back into the new program
[14:14:10] * myself achieves nirvana
[14:14:19] <trackk> haha
[14:14:20] <trackk> @_@
[14:14:44] <trackk> ok, then I guess I don't need an extra uC
[14:16:28] <N2TOH> when will the price of the 1284p drop so it can stop being the red headed step child in a 40 pin PDIP?
[14:20:31] <malinus> wtf atmega1284 is expensive!!!!
[14:21:39] <myself> use the atmega1284rfr and ignore the RF pins, make a breakout board and it's still cheaper
[15:25:46] <N2TOH> what is the price on the 1284rfr? the PDIP40 is about $8USD
[15:34:15] <myself> about half that
[16:24:27] <ambro718> Hey, does someone understand how these special cases in PWM work? " The extreme values for the OCRnx Register represents special cases when generating a PWM waveform output in the fast PWM mode. If the OCRnx is set equal to BOTTOM (0x0000) the output will be a narrow spike for each TOP+1 timer clock cycle. Setting the OCRnx equal to TOP will result in a constant high or low output (depending on the polarity of the output set by the COMnx1:0 bits)
[16:24:29] <ambro718> .
[16:25:33] <ambro718> How do I achieve duty factor TOP/(TOP+1) (almost always on, but off at the last clock period)
[16:27:10] <ambro718> I suspect it could be that "narrow spike" it's talking about but that sentance is vague to me.