Back
[03:26:42] <lolololol> so, to filter noise on my adc-inputs i can just use a simple low-pass rc filter right?
[03:28:19] <Tekkkz> Hello!
[03:30:22] <malinus> lolololol: look in the datasheet. There is an example schematic.
[03:39:53] <lolololol> malinus: there isnt
[03:40:51] <lolololol> it just says "The user is advised to remove high frequency components with a low-pass filter before applying the signals as inputs to the ADC."
[04:05:14] <EI24> hi, is there someway to debug my code without haveing JTAG debugger/programmer
[04:05:29] <EI24> having a JTAG debugger/programmmer*
[05:15:04] <lolololol> EI24: define debug
[05:15:17] <lolololol> you can just set leds or print on uart to debug imo
[05:18:46] <EI24> lolololol: some way to run through the code, but stepwise, showing what happens each step
[05:19:04] <EI24> so i can read through the code, and see what wrong
[05:45:06] <lolololol> then no
[05:45:21] <lolololol> unless you place wait-conditions on each place you want to step
[05:45:30] <lolololol> and then step by toggling a pin or something
[06:31:48] <malinus> My cats face on a pcb -
http://imgur.com/uxt5Q4g figured some one might enjoy.
[06:53:33] <phinxy> hey, if i want to change a china brand audio DAC's capacitors to geniune ones, where should i buy them? (EU shipping=
[07:16:32] <phinxy> i ordered them at hificollective.
[08:20:14] <Ad0> what do you do when you run out of IO ?
[08:20:25] <Ad0> if you want to read 64 analog ins
[08:32:35] <Lambda_Aurigae> analog multiplexer
[08:34:48] <phinxy> what do you trade off for more IOs? R/W speed?
[08:35:10] <Ad0> does it run on a clock or something
[08:35:29] <phinxy> everything runs on a clock? =D
[08:35:56] <Ad0> lol
[08:37:06] <Ad0> isn't the adc already multiplexed?
[08:54:31] <Ad0> yup it is
[09:25:28] <Casper> you can stop using the build in multiplexer and use an exernal one
[09:25:48] <Casper> you could also connect multiple external ones to the internal one
[09:26:03] <Casper> you can use an external dac or 64
[09:26:29] <Casper> or get another microcontoller with enought io
[09:57:13] <Ad0> yeah
[10:07:00] <Ad0> how do you time how many cycles and time a loop in the main loop takes_
[10:07:02] <Ad0> ?
[10:09:50] <Lambda_Aurigae> look at the assembly listing and figure out how many cycles each instruction takes.
[10:11:04] <Ad0> that's a bit heavy since there can be a fair bit of instructions hehe
[10:11:08] <RikusW> or use the atmel simulator to count it for you
[10:11:13] <Ad0> simulkator should know
[10:11:13] <Lambda_Aurigae> you asked how I do it.
[10:11:15] <Lambda_Aurigae> that's how I do it.
[10:11:17] <Ad0> yeah
[10:30:06] <Ad0> 22.52 celcius at the office lulz
[10:31:13] <Lambda_Aurigae> 17.8C here.
[10:42:48] <Tom_itx> 60f
[10:55:32] <LeoNerd> To follow up from yesterday: my optoisolators are being much better-behaved today. I now have much more sensible resistors on it
[10:55:56] <LeoNerd> I think the trouble was wayyyy too low forward-current in the LED and way too low biasing current in the transistor. Now those are both higher it seems fine
[10:56:05] <LeoNerd> I'm getting between 2 and 3µs both rise and fall time :)
[11:02:03] <Ad0> hehe
[11:02:51] <Ad0> 16 mhz = 62.5 ns
[11:03:27] <Ad0> so it would be 48 clock cycles
[11:03:32] <Lambda_Aurigae> give or take.
[11:03:47] <Ad0> on the opto isolator in comparison
[11:03:57] <Ad0> I guess opto isolators are slow by nature
[11:04:01] <Lambda_Aurigae> yup.
[11:04:14] <Lambda_Aurigae> gotta take into account rise and fall time of both the emitter and sensor.
[11:04:14] <Ad0> that's actually a problem in music production gear
[11:04:22] <Ad0> a lot uses opto isolator so you get analog latency :)
[11:04:26] <LeoNerd> It's a serial link between two stations separated by ~100m of cable. It only has to carry LED and button status information
[11:04:31] <Ad0> especially if you have DI boxes
[11:04:40] <Ad0> phasing issues
[11:04:41] <Lambda_Aurigae> no clue what DI boxes are.
[11:04:48] <LeoNerd> So I'm running it at 50kHz; i.e. clock pulses of 100µsec high or low. So this time is fine fo rme
[11:04:53] <aandrew> there are some little tricks you can use to speed up optos too:
http://electronics.stackexchange.com/a/136944/17429
[11:04:55] <Ad0> hehe LeoNerd
[11:06:12] <aandrew> LeoNerd: clearly you need a 10GbE link
[11:06:34] <Lambda_Aurigae> TB data link..
[11:06:47] <Lambda_Aurigae> maybe even a 10TB link.
[11:07:29] <Ad0> Lambda_Aurigae: boxes that isolate signals so you get rid of ground loop issues etc
[11:07:38] <Lambda_Aurigae> oh.
[11:07:58] <Lambda_Aurigae> well, music sucks for the most part anyhow.
[11:08:26] <Lambda_Aurigae> so ground loops are good...make the noise makers not work anymore.
[11:15:10] <LeoNerd> I wonder now though if I can string *two* of these isolators together in series; one at each end of the cable
[11:40:25] <Lambda_Aurigae> LeoNerd, you will need power on the cable itself.
[11:40:39] <Lambda_Aurigae> a separate power source to get true isolation.
[11:42:46] <Lambda_Aurigae> and definitely turn those phototransistors into darlington pairs...will make them trigger much better.
[11:54:24] <LeoNerd> Lambda_Aurigae: I've got a handy supply of 0505s so that part's easy :)
[12:22:05] <Ad0> passive isolators?
[12:34:32] <Lambda_Aurigae> you can do such with magnetics
[12:34:54] <Lambda_Aurigae> but not with the kind of comms I think he is using.
[15:03:24] <GeneialM> hi
[15:03:27] <GeneialM> i'm fairly new to PCB design and i'm using Altium. For my design I wanted to resistors but there are so many different manufacturers
[15:03:32] <GeneialM> Is it possible to have a generic footprint that i can use for various sizes of resistors and different manufacturers?
[15:06:58] <Ad0> what tolerance do you need etc
[15:08:20] <Ad0> normal resistor
[15:11:11] <GeneialM> i dont know to be honest, i was looking at 10k, 110k, 330 ohm resistors
[15:11:21] <GeneialM> you know, stuff you'd find in a simple resistor kit
[15:11:28] <GeneialM> except i wanted to go the surface mount route
[15:29:45] <Lambda_Aurigae> there are several SMT size standards and most PCB drawing software supports the standard pad layouts.
[15:40:54] <avr929> Hello
[15:41:37] <avr929> Anyone on here have experience working with i2c?
[15:43:10] <Lambda_Aurigae> lots of people do.
[15:43:42] <avr929> I'm trying to use an AVR to read data from an I2C sensor that's in a different circuit
[15:43:45] <Lambda_Aurigae> you have now used up your one free question..Yoy will be charged $0.25 for each future question.
[15:44:20] <avr929> like a probe.. so it wouldn't be acting as either master or slave, just listening.. was wondering if there is a good way to do this
[15:44:23] <avr929> lol
[15:44:33] <Lambda_Aurigae> you have to be either master or slave.
[15:44:51] <Lambda_Aurigae> it might be possible to play sniffer on an i2c bus
[15:44:59] <Lambda_Aurigae> but that is going to require some special programming.
[15:46:49] <Lambda_Aurigae> basically what you are wanting to do is make a logic sniffer that speaks i2c protocol.
[15:47:45] <avr929> yes. What I am trying to do is read from a sensor that already has a master
[15:48:01] <Lambda_Aurigae> you will only be able to read the data as the master is reading it.
[15:48:50] <Lambda_Aurigae> if you want to read it without the existing master being active then you will need to setup your device as master..
[15:49:06] <avr929> That's fine, I don't need the ability to independently poll it. I just want to read it whenever the other master reads it
[15:49:32] <Lambda_Aurigae> then you set it up to watch the two lines and record the data on them..
[15:49:41] <Lambda_Aurigae> then you will need some software to decrypt that data.
[15:53:36] <avr929> Okay. So if I were to, say, set up an interrupt on an input pin on the AVR to wait for the slave to output data, and then record what it transmits, I could achieve this functionality?
[16:32:40] <Lambda_Aurigae> I suggest looking at the i2c protocol spec before asking further questions..but, he is gone.
[16:49:41] <Tom_itx> and that's life on irc.
[16:49:52] <Lambda_Aurigae> yup.
[19:44:42] <ferdna> everyone watching the fight tonight?
[19:45:57] <Lambda_Aurigae> nobody fighting around here.
[19:46:15] <Lambda_Aurigae> the nephew's kids all left already.
[19:46:24] <Lambda_Aurigae> I'm sure there is probably fighting in the back of their car still though.
[21:10:07] <ferdna> Lambda_Aurigae, hehehe