Back
[00:12:11] <frankd> whats the best way to get multiple DACs hooked up to an Arduino Due (ATSAM3XE)?
[00:12:42] <frankd> i realize its not AVR and Cortex-M but was hoping someone might have an idea :D
[00:22:00] <Mr_Sheesh> SPI or I2C DACs?
[00:23:59] <Casper> frankd: thanks for specifying which µC it use, usually people don't even know what is an AVR...
[00:26:34] <frankd> Mr_Sheesh, or I2S? :) I haven't purchased any DACs yet, I want to run some FIR filters and need to pass the output to each amplifier for each speaker (sub, woofer, mid, tweeter)
[00:26:53] <frankd> so i need 4 DAC channels per speaker (atleast 2 speakers) and 2 more for a center speaker
[00:28:35] <frankd> Casper, yeah, I heard of an "overclocked Arduino to 65MHz" or something and I was like you mean an overclocked AVR8 ATMega328? :P
[00:38:25] <Casper> frankd: and their reply: what is an atmega?
[00:54:13] <frankd> Casper, haha yeah
[00:54:34] <frankd> to which I replied "its an AT that's bigger than an ATTiny"
[00:56:18] <frankd> uh oh
[00:56:23] <frankd> im down to 15 TL072s
[00:56:45] <frankd> i should really throw some NE5532s in the mix, and just use the TL072s for input buffers
[01:01:48] <Mr_Sheesh> SPI might be better for speed, but "it depends"...
[01:03:24] <frankd> 44.1KHz * 16 bits = 705,600kbit/s just for one channel
[01:03:44] <frankd> dunno if SPI will cut it to feed 10 DACs
[01:04:31] <Mr_Sheesh> TWI / I2C / I2S going to do it tho?
[01:04:36] <Mr_Sheesh> IDK why 10 DACs
[01:12:52] <frankd> Mr_Sheesh, I just explained why.. each speaker has its own amplifier
[01:13:22] <frankd> need FIR filters on each amplifier to feed the correct frequencies to it
[03:24:18] <Haohmaru> anyone familiar with the ATWINC1500 wifi module?
[03:34:07] <Haohmaru> i can't tell if it is able to open more than 1 tcp socket at once
[06:40:18] <Lambda_Aurigae> frankd, does the chip on board have multiple i2c, i2s, or spi hardware channels?
[09:06:52] <megal0maniac> RikusW: Hi!
[09:07:00] <RikusW> Hi megal0maniac
[09:07:25] <RikusW> megal0maniac: Look at the price.... ->
http://www.loot.co.za/product/otmar-kilgenstein-switched-mode-power-supplies-in-pract/pylb-392-g720
[09:07:25] <megal0maniac> Hoe gaanit? :)
[09:07:41] <RikusW> Going well :)
[09:07:49] <RikusW> Hows things in CT ?
[09:08:49] <megal0maniac> Wow. I'll take the PDF, thanks! Would be a cool book though
[09:09:05] <megal0maniac> All good here. Spending a week on a farm in Natal later this month though
[09:09:19] <RikusW> Where in Natal ?
[09:09:28] <megal0maniac> Just south of PMB
[09:10:08] <RikusW> Are you going along the coast or via Bloemfontein ?
[09:10:25] <megal0maniac> Flying to DBN :P
[09:10:30] <megal0maniac> Then getting a lift
[09:10:30] <RikusW> nice
[09:10:56] <RikusW> My brother got a job on CT, doing arm stuff
[09:11:02] <RikusW> *in
[09:11:21] <megal0maniac> Oh nice. It's a good place to be
[09:11:39] <megal0maniac> Have you played with the ESP8266?
[09:11:41] <RikusW> He is working for a company doing
https://en.wikipedia.org/wiki/Audio_Video_Bridging
[09:12:00] <RikusW> I've seen the ESP8266, don't have one
[09:13:14] <megal0maniac> Definitely worth getting your hands on one/some
[09:13:30] <megal0maniac> Just got the toolchain up and the SDK is quite nice, very extensive
[09:13:38] <RikusW> He is working for
http://www.umannet.de/en/
[09:14:06] <megal0maniac> TThhaatt''ss aa vveerryy ccooooll ffiieelldd
[09:14:36] <RikusW> They are doing implementations for high end cars
[09:14:49] <megal0maniac> Aaah! PuTTY fail
[09:15:10] <megal0maniac> What are you busy with at the moment? Do you know where all the cattle is? ;)
[09:15:32] <RikusW> http://tahmidmc.blogspot.co.za/p/blog-page.html
[09:16:11] <RikusW> The cattle is going nuts in search of some green grass atm, and we're still waiting for rain.
[09:16:35] <megal0maniac> It's coming soon though, no?
[09:16:46] <megal0maniac> October == thundershowers
[09:16:59] <RikusW> Hope so
[09:17:15] <RikusW> Doing some research on smps this morning
[09:17:18] <RikusW> https://www.loot.co.za/search?cat=b&terms=Switching+Power+Supplies
[09:17:29] <RikusW> Seems the books are 1 or 2k...
[09:17:47] <megal0maniac> It's a black magic field
[09:18:00] <RikusW> http://www.loot.co.za/product/abraham-i-pressman-switching-power-supply-design/mmvw-486-g310
[09:19:32] <RikusW> I have repaired a lot of PC smps, but designing one is something else...
[09:19:59] <RikusW> I did manage a 12V to 350V stepup, just don't know its power rating...
[09:20:36] <megal0maniac> I tried to fix one once, ended up handing it to someone else
[09:21:12] <RikusW> Those are rather simple to me now :)
[09:21:37] <RikusW> Most often its the caps, and you need low esr
[09:21:50] <megal0maniac> One of the rectifying diodes blew on the HV side so the controller went into shutdown and I got 0V on LV
[09:21:59] <RikusW> Mantech lists those as LIHT (low impedance high temp)
[09:22:11] <megal0maniac> And everything was covered in that horrible goo
[09:22:20] <megal0maniac> So you had to dig for components
[09:22:22] <RikusW> you mean the bridge rectifier ?
[09:22:26] <megal0maniac> Yeah
[09:22:53] <megal0maniac> Or maybe a smoothing cap, I can't remember.
[09:22:59] <megal0maniac> But the result was the same
[09:23:25] <RikusW> You need to check the power transistors too...
[09:23:31] <megal0maniac> Was a cheapie PSU for a R12K cisco switch
[09:23:40] <megal0maniac> Well the other guy fixed it and now it's working
[09:23:45] <megal0maniac> And explained what was wrong
[09:27:30] <RikusW> My procedure goes something like this:
[09:27:51] <RikusW> If the fuse is blown, I check the bridge and power transistors
[09:28:13] <RikusW> If not I still check those, and also look for swollen or leaking caps
[09:29:21] <RikusW> On 5Vsb I usually check the components one by one...
[09:29:59] <RikusW> and the LV diodes sometime fail too
[09:30:51] <RikusW> megal0maniac: you mean covered in silicone ? some smps have those :/
[09:31:09] <RikusW> makes it quite hard to repair
[09:31:40] <megal0maniac> Yeah, that icky yellow stuff
[10:15:46] <rue_school> its always caps, just that sometimes they cause other things to burn out too
[10:16:08] <rue_school> bad solder joints dont seem to be so common anymore
[10:49:39] <CasperAtwork> no, they switched to brittle ball
[10:49:50] <CasperAtwork> and evil whisker
[11:59:28] <rue_school> heh, lead free
[11:59:56] <rue_school> I wonder what does more environmental damage, the lead or the turnover from being lead free
[12:01:13] <learath> I'm going to bet the turnover
[12:01:22] <learath> a good older board can last 30 years
[12:03:31] <rue_school> +- caps
[12:03:46] <rue_school> which if caught early enough, aren't a problem
[12:04:07] <rue_school> even the caps used back in the radio tube days didn't last forever, so, all around, no blame
[12:04:30] <rue_school> vacuum tube...
[12:07:29] <learath> eh, the board is fine if the caps die, some minor resoldering
[12:10:32] <rue_school> indeed
[12:10:43] <rue_school> i a BGA fails, well, usually screwed
[12:10:59] <rue_school> I got a reballing mask to play tho
[12:11:05] <rue_school> need to work out how to make balls
[12:11:14] <rue_school> I think air an liquid solder
[12:11:20] <rue_school> then sift them
[12:11:31] <rue_school> I wonder how big my balls need to be
[13:28:36] <CasperAtwork> pretty small
[13:28:42] <CasperAtwork> just buy some one the bay?
[15:32:44] <frankd> Lambda_Aurigae, the STM32 boards I have do, yes
[18:00:25] <rue_house> I'm back
[18:06:34] <Lambda_Aurigae> I'm front.
[22:09:07] <RossMcK> Afternoon all