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[05:47:08] <LeoNerd> Hmm... preliminary PCB design done. It's big.. and therefore expensive. :(
[05:47:39] <LeoNerd> Just wondering now if I can squeeze enough space out of it by swapping to some SMT devices, saving board space and therefore cost, but then having to buy said SMT componens
[05:47:42] <LeoNerd> +t
[06:15:23] <nuxil> help.. my 3rd pwm on my tiny85 isnt working. :( .. this is how i init my pwms,
http://pastebin.com/i5DtwVcy
[06:15:59] <nuxil> both OCR0A , OCR0B is working fine.. i checked it with my oscilliioscope
[06:16:05] <nuxil> but OCR1B isnt working
[06:16:07] <nuxil> ideas ??
[06:16:33] <LeoNerd> OCR1 is on timer1, not timer0 like the other two pins
[06:16:39] <LeoNerd> Did you remember to initialise that too?
[06:17:20] <nuxil> hmm
[06:17:31] <nuxil> i thought i had done it
[06:17:55] <nuxil> timer 0 A side. timer 0 b side. and timer 1.
[06:19:57] <LeoNerd> Ooooooh... new AVR chip. The ATmega328PB
[06:20:01] <LeoNerd> There's a B revision
[06:20:11] <LeoNerd> *five*.. count them *five* timer units, two UARTs
[06:20:12] <nikomo> made an led blink yay...
[06:20:41] <LeoNerd> Two SPI and two I²C units..
[06:20:48] <LeoNerd> Dude you're going to run out of pins
[06:20:50] <nuxil> LeoNerd, doesnt this init the timer1 ? TCCR1 = _BV (CS10);
[06:22:15] <LeoNerd> I forget offhand...
[06:22:53] <LeoNerd> Timers in particular are one AVR detail I find that varies around far too much. I write the code once in my standard set of libraries then try to flush the code out of my head to save space for more useful information
[06:23:23] <nuxil> lol
[06:24:16] <LeoNerd> Huhh... It's a 32pin QFP-only device
[06:24:20] <LeoNerd> No PDIP, no SOIC
[06:25:34] <LeoNerd> So adds four new pins, PE0-PE3
[06:29:35] <tkoskine> Mouser seems to have 328pb chips in stock already.
[06:30:03] <LeoNerd> Mm.. nice
[06:51:29] <WormFood> Does anyone know, where I can find the technical details on Qualcom's Quick Charge system. I want to be able to massage the Quick Charger into giving me the additional 9 and 12 volts it's capable of producing.
[07:09:53] <nuxil> https://www.qualcomm.com/news/snapdragon/2015/06/30/qualcomm-quick-charge-20-technology-explained ?
[07:10:20] <WormFood> Sadly, that doesn't give me the technical specifics of the system. I need to know what to feed it, to make it give me 9 and 12 volts.
[07:11:56] <nuxil> you feed it 5V ?
[07:12:08] <nuxil> its a usb charger
[07:13:09] <WormFood> nuxil, huh? Did you not even read that page?
[07:13:17] <nuxil> nah :p
[07:13:28] <Lambda_Aurigae> the system uses the D+ and D- lines to negotiate a higher charge voltage.
[07:13:29] <WormFood> It's not a usb charger
[07:13:40] <Lambda_Aurigae> it starts at 5V just like a regular usb charger.
[07:13:43] <WormFood> Lambda_Aurigae, but how? What are the technical specifics?
[07:13:46] <Lambda_Aurigae> then the device requests more power.
[07:13:56] <WormFood> And, I believe it makes a USB connection to the charger, to control it.
[07:13:59] <nuxil> but it sais. Quick Charge 2.0 using a conventional (5 volt, 1 amp)
[07:14:12] <Lambda_Aurigae> WormFood, classified...aka patented.
[07:14:20] <WormFood> no
[07:14:25] <WormFood> patented = unclassified
[07:14:32] <Lambda_Aurigae> so look up the patent.
[07:14:45] <WormFood> in order to get the patent, they have to give the details of how it works, in exchange for limited protection.
[07:14:52] <Lambda_Aurigae> or, hook a logic analyzer to the D+ and D- lines of something using it and reverse engineer it.
[07:15:09] <WormFood> I'm 99% sure, it's creating a USB connection to control the charger
[07:15:15] <Lambda_Aurigae> probably.
[07:15:21] <WormFood> I'm starting to find more information about it, including control ICs
[07:17:29] <Lambda_Aurigae> https://blog.oxplot.com/quickcharge/
[07:17:31] <Lambda_Aurigae> there
[07:17:32] <Lambda_Aurigae> solved
[07:17:35] <Lambda_Aurigae> no usb connection.
[07:17:51] <Lambda_Aurigae> there is a graphic about halfway down the page that shows what you need.
[07:18:25] <Lambda_Aurigae> it uses 0.6V and 3.3V on the D+ and D- lines to specify the charger voltage.
[07:18:27] <WormFood> awesome Lambda_Aurigae! That's what I'm looking for.
[07:18:41] <Lambda_Aurigae> that will be 10 dollars US for the google search please.
[07:18:48] <nuxil> lol
[07:19:11] <WormFood> Lambda_Aurigae, I've been searching for a few days, and haven't been able to find it. And, unfortunately, I don't have access to google.
[07:19:16] <Lambda_Aurigae> qualcomm quick charge communications protocol
[07:19:21] <Lambda_Aurigae> in google
[07:19:26] <Lambda_Aurigae> third link from the top on my search.
[07:19:50] <WormFood> I couldn't think of exactly what to search for, but I've been getting closer and closer. This is perfect, and exactly what I need.
[07:20:02] <Lambda_Aurigae> search for what you asked.
[07:20:17] <WormFood> I did
[07:20:39] <Lambda_Aurigae> off to work for me..laters.
[07:21:04] <WormFood> Believe me, I'm pretty good at finding stuff, but this particular subject was thwarting me. even with my shit search engines, I'm still pretty good about finding the info I want, but not this time.
[07:21:10] <WormFood> Thanks again Lambda_Aurigae.
[08:28:28] <aandrew> morning WormFood
[08:28:31] <aandrew> how's things?
[09:10:00] <lorenzo> I'm starting to think I've got a bad batch of atmega32u4
[09:10:31] <lorenzo> I'm connecting nothing but power to pins 35/34 and I get ~ 500mA draw
[09:15:06] <LeoNerd> 500mA sounds excessive yes
[09:15:22] <LeoNerd> Are they the only power pins, or are there more you need to use too?
[09:16:27] <lorenzo> only power pins, I'm only powering the chip
[09:16:40] <lorenzo> if I use 14/15 instead of 34/35 it doesn't happen
[09:16:51] <LeoNerd> Yah that's what I mean - aren't there duplicate VCC/GND pins?
[09:17:10] <lorenzo> yeah there are 2x4
[09:17:18] <lorenzo> gnd/vcc, gnd/vcc, ugnd/uvcc, agnd,avcc
[09:18:32] <LeoNerd> Ignore the U ones.. they're for the USB module
[09:19:01] <lorenzo> yeah, and A should be for adc
[09:19:46] <lorenzo> I've tried powering it via both vcc/gnd on 34,35 + 14,15
[09:19:49] <lorenzo> same issue
[09:20:49] <LeoNerd> Hmm... sounds suspect at least.. is it a new unprogrammed chip?
[09:20:58] <lorenzo> yeah just got it from atmel
[09:28:18] <WormFood> evening aandrew, things are going well. How about you?
[11:07:01] <lorenzo> LeoNerd: fixed it
[11:07:06] <lorenzo> it was flux residue on the board shorting the pins :p
[11:07:26] <LeoNerd> Ah :)
[11:07:29] <LeoNerd> Yes that'll do it :)
[11:07:43] <LeoNerd> Though... conductive flux?
[11:08:20] <lorenzo> no idea, probably got burnt a bit, resistance was around 500 ohms
[11:08:27] <lorenzo> washed the board in some cleaner and it's back working now
[11:08:44] <LeoNerd> 500ohms, and it was passing 500mA ?
[11:09:34] <LeoNerd> ... did you put a 250V across it?
[11:12:24] <lorenzo> LeoNerd: haha no, 3.3V
[11:12:29] <lorenzo> no idea what happened really :/
[11:12:43] <lorenzo> quite sure it looked like flux or something
[11:14:20] <LeoNerd> Hmm.. Also, as a general suggestion, I'd suggest getting an adjustable bench supply of some kind
[11:14:45] <LeoNerd> Being able to set a current limit much below 500mA would be nice. :) I usually power up a bare chip with no other peripherals at something like 20mA
[11:15:00] <lorenzo> yeah I have one
[11:15:08] <lorenzo> I should short it, set the current to something low
[11:27:48] <jben> Always for the same problem I had before, I have a question
[11:28:17] <jben> is PDI always enabled for a xmega (a new one)?
[11:28:38] <WormFood> jben, check your datasheet for the part in question
[11:28:52] <LeoNerd> There's probably a fuse that controls it
[11:32:13] <Lambda_Aurigae> jben, I would think so as it is needed for programming unless you have a bootloader onboard.
[11:39:44] <jben> it is what I think
[11:40:05] <jben> does somebody understand the schematics 29-2 in
http://www.atmel.com/Images/doc8077.pdf
[11:40:08] <jben> ?
[11:40:48] <LeoNerd> Mm?
[11:40:49] <Lambda_Aurigae> what page?
[11:40:58] <LeoNerd> 339
[11:41:10] <LeoNerd> It's just showing the interconnectedness of some internal blocks in the chip, in case you're interested
[11:46:05] <jben> LeoNerd: oh, it is the *internal* side
[11:46:08] <jben> right
[11:46:23] <LeoNerd> Yah it's just for interest
[11:46:57] <jben> but what is the "connector"?
[11:47:25] <LeoNerd> What connector?
[11:47:53] <jben> in the fig 29-2
[11:48:04] <Lambda_Aurigae> I think that is actually the way you connect it on the board.
[11:48:07] <Lambda_Aurigae> not the internals.
[11:48:36] <LeoNerd> Ah; 29-2 is, yes.
[11:48:39] <LeoNerd> Iwas looking at 29-1
[11:48:58] <LeoNerd> 29-2 is suggesting a schematic layout, yes. "connector" is just whatever connector you've chosen to use
[11:49:05] <LeoNerd> I dno't think Atmel make a specific suggestion on that
[11:49:30] <LeoNerd> Things like 2x5 or 2x3 for ISP have sprung up a defacto standards, but they're just suggestions. PDI I believe is similar
[11:49:52] <LeoNerd> I've done mixed ISP and other SPI over a DE-9 connector before :)
[11:50:05] <jben> but, PDI use 4 wires (PDI_CLK, PDI_DATA, Vcc, GND), this connector have 5, PDI_CLK sir wired direcly to Vcc, I don't ungerstand nothing
[11:50:15] <Lambda_Aurigae> I used to do a lot of ISP on 6p6c modular phone connectors.
[11:50:27] <LeoNerd> I think they've just mislabled it and added VCC twice
[11:50:37] <LeoNerd> er..
[11:50:53] <LeoNerd> Yeah.. that diagram just looks confused. I'd ignore it
[11:51:00] <jben> Yes, for the connector I have myself also strange stuff, but, with the same number of wires (or spares N.C. pins)
[11:51:02] <Lambda_Aurigae> it does look pharked.
[11:56:11] <jben> ok, I will continue to use the schematics on page 15 on
http://www.atmel.com/Images/doc8278.pdf
[11:57:38] <LeoNerd> That looks much more sensible
[11:58:13] <LeoNerd> 2x3?
[11:58:21] <LeoNerd> Heh.. it only needs 4 pins. I'd have used a 1x4
[11:58:53] <Lambda_Aurigae> 4p4c modular phone handset plug!
[11:59:05] <LeoNerd> Huh though this diagram reminds me I forgot to add the second decoupling cap on my 328P board
[11:59:17] <LeoNerd> Good thing it's not committed to fab yet :)
[11:59:24] <jben> LeoNerd: it is not the connector the point, I don't mind of the connector, but the pull-up of PDI_CLK to Vcc
[11:59:27] <LeoNerd> I can squeeze one little 0603 in.. how hard can it be? ;)
[11:59:33] <LeoNerd> jben: yus
[12:00:01] <N1njaneer> LeoNerd: General good practice when doing layout is looking at the nets and ensuring you see a decoupling cap whenever you see a VCC net pin coming off the chip :)
[12:00:08] <N1njaneer> You can never have too many!
[12:00:19] <LeoNerd> Weeeellll.... to a point
[12:00:21] <LeoNerd> :)
[12:00:44] <LeoNerd> Also hi
[12:01:18] * LeoNerd tries not to get distracted by that today though; $work to do first ... mumble mumble
[12:01:37] <Lambda_Aurigae> jben, it's an open collector connection on the chip I bet.
[12:02:04] <jben> Lambda_Aurigae: that's the point
[12:02:06] <N1njaneer> LeoNerd: On some of the bigger FPGAs and such it's not uncomming to have a dozen or more, minimum :)
[12:02:11] <N1njaneer> +uncommon
[12:02:14] <LeoNerd> Mmmm
[12:02:15] <Lambda_Aurigae> N1njaneer, those of us who learned on 74xx series chips know all about decoupling caps.
[12:02:21] <jben> I have 2.7V on the pin, Vcc is 3.3V, I don't understand
[12:02:56] <Lambda_Aurigae> 50 7400 chips, 50 decoupling caps.
[12:03:25] <Lambda_Aurigae> jben, 2.7V is within range of the logic levels.
[12:03:26] <LeoNerd> Big black rectangle, little brown disc, big black rectangle, little brown disc, ....
[12:03:42] <Lambda_Aurigae> LeoNerd, yup.
[12:03:57] <LeoNerd> I fear for the inrush current to a board with 50 decoupling caps
[12:03:58] <Lambda_Aurigae> I often put them under the sockets.
[12:04:15] <N1njaneer> LeoNerd: With 0.1uf? Nah.
[12:04:37] <LeoNerd> Hrm... I suppose individually they're quite small
[12:04:38] <Lambda_Aurigae> that's why I powered my stuff with a 6V tractor battery charger....that sucker could jump start a tractor on a cold morning.
[12:05:02] <Lambda_Aurigae> current limited to 650A I think.
[12:05:06] <N1njaneer> I have 8800uf of bulk capacitance on one of our board designs. With that you have to use inrush protection to keep from blowing the fuse, but ONLY if not powered from a non-Class 2 supply, which the device is strictly forbidden to be powered by.
[12:05:15] <Lambda_Aurigae> ok...300A more likely.
[12:05:40] <LeoNerd> N1njaneer: My "high-precision" DC PSU test dummy load (
https://twitter.com/cpan_pevans/status/677454666934931458) has quite the inrush current ;)
[12:05:46] <Lambda_Aurigae> but it was bigger than a geo metro engine.
[12:06:02] <N1njaneer> But even with several hundred uf of bulk capacitance it's generally not much of an issue
[12:06:50] <Lambda_Aurigae> LeoNerd, know what else those car lightbulbs are good for? using a standard car battery charger to charge a gell cell battery...put a bulb in line and it gives you some limiting on the charge.
[12:06:56] <N1njaneer> I generally put AT LEAST a 100uf cap on the input of most of my boards, before the DC/DC or linear regulators. If you are powering over a significant length of cable it's generally important to do.
[12:07:32] <LeoNerd> Yah; 10 or 100uF on the board at the power connector, and 100nF per chpi
[12:07:33] <LeoNerd> chip
[12:08:21] <Lambda_Aurigae> 4700uF...I have a box of the dang things...one on every board....just for the hell of it...and because I bought 10K of them 20 years ago and still haven't emptied half the crate.
[12:08:53] <LeoNerd> Hehe
[12:09:18] <Lambda_Aurigae> 4700uF 30V axial lead.
[12:09:32] <jben> Lambda_Aurigae: nearly same here, Il have a lot of 4700u... in 25V
[12:09:37] <Lambda_Aurigae> I once wired up 100 of them in parallel just to see what it would do.
[12:09:49] <jben> all my power line are 48V, I can't use them :(
[12:09:50] <Lambda_Aurigae> knocked the shit out of the kid who grabbed the wires.
[12:11:33] <apo_> sounds like a good teachable moment
[12:13:22] <Lambda_Aurigae> yup.
[12:13:33] <Lambda_Aurigae> this is what 24V will do if you grab the wrong wire.
[12:14:08] * N1njaneer has to go through all of the stencils today, find the ones needed for production, and gather the files up to have them reworked with fidicuals on the bottom.
[12:15:42] <N1njaneer> I also found out our stencil manfacturer can easily do reworks - if you just need additional apetures added they can just add them, rather than having to $$$ for a completely new stencil
[12:16:30] <Lambda_Aurigae> some 6 year old chinese kid with a hole punch.
[12:16:53] <WormFood> Does anyone know, off-hand, where there is a list of AVR devices, and their general capabilities?
[12:17:00] <Lambda_Aurigae> atmel.com
[12:17:28] <Lambda_Aurigae> http://www.atmel.com/v2PFResults.aspx#%28actives:!%288238,8394,8362,8282,8431,8300,8358,8392,8378,8445,8236,8449,8474,8248,8264,8447,8256,8254,8286,8462,8429,8458,8466,8400,8302,8278%29,data:%28area:%27%27,category:%2734864[33180]%27,pm:!%28%28i:8238,v:!%281,16%29%29,%28i:8394,v:!%280,17%29%29,%28i:8362,v:!%282,29%29%29,%28i:8282,v:!%286,7%29%29,%28i:8431,v:!%281,33%29%29,%28i:8300,v:!%281,8%29%29,%28i:8358,v:!%282,71%29%29,%28i:8392,v:!%280,1%29%29
[12:17:29] <Lambda_Aurigae> ,%28i:8378,v:!n%29,%28i:8445,v:!%281,4,5,6,7,9%29%29,%28i:8236,v:!%280,24%29%29,%28i:8449,v:!%281,10%29%29,%28i:8474,v:!%280%29%29,%28i:8248,v:!%280,1%29%29,%28i:8264,v:!%281,5%29%29,%28i:8447,v:!%280,1%29%29,%28i:8256,v:!%281,2,4%29%29,%28i:8254,v:!%284,18%29%29,%28i:8286,v:!%280,3%29%29,%28i:8462,v:!%280,8%29%29,%28i:8429,v:!%281,10%29%29,%28i:8458,v:!%280,4%29%29,%28i:8466,v:!%281,2,5%29%29,%28i:8400,v:!%280,20%29%29,%28i:8302,v:!%280,1%29%29,%28
[12:17:29] <Lambda_Aurigae> i:8278,v:!%280,1,2%29%29%29,view:list%29,sc:1%29
[12:17:36] <Lambda_Aurigae> that doesn't past well.
[12:17:37] <WormFood> You might as well say "the Internet". I was looking for the actual page. If you don't have it off-hand, that's fine.
[12:18:04] <Lambda_Aurigae> http://www.atmel.com/products/microcontrollers/avr/default.aspx
[12:18:08] <Lambda_Aurigae> product search tab
[12:19:03] <WormFood> not exactly what I was looking for, but close enough
[12:19:11] <WormFood> Thanks again Lambda_Aurigae
[12:19:15] <Lambda_Aurigae> welcome.
[12:19:24] <Lambda_Aurigae> that's the closest to what you asked that I know of..
[12:19:33] <Lambda_Aurigae> all the features listed out there to search through.
[12:19:53] <Lambda_Aurigae> including package and speed and memory and peripherals
[12:20:12] <WormFood> I thought I remembered seeing a table somewhere, with all of their features in columns, like timers and uart count, and stuff like that.
[12:20:20] <Lambda_Aurigae> if you don't see a parameter you can click the blue button to show/hide the ones you want.
[12:20:35] <Lambda_Aurigae> that's on that page...you can expert it to excel too.
[12:21:37] <WormFood> hhhmmm...it seems Atmel has removed the tables I was thinking of.
[12:21:41] <Lambda_Aurigae> http://www.atmel.com/products/microcontrollers/avr/default.aspx
[12:21:53] <Lambda_Aurigae> second tab, labeled product search....has all that info.
[12:22:09] <Lambda_Aurigae> a searchable and adjustable table.
[12:22:15] <N1njaneer> Lambda_Aurigae: Actually no, they're 20 minutes from here. I just drive over :)
[12:23:26] <WormFood> hhhmmm...perhaps that is the table I was thinking of....but I'm pretty sure it used to be just static tables (this one uses a lot of javashit to load it)...but that is exactly what I was looking for.
[12:23:40] <Lambda_Aurigae> yeah.
[12:23:49] <Lambda_Aurigae> just download the excel version...button at the top of the page.
[12:23:57] <Lambda_Aurigae> it changed over the years.
[12:24:05] <Lambda_Aurigae> used to be static then they made it "better"
[12:24:23] <WormFood> yeah, because dynamic is always "better"
[12:25:42] <Lambda_Aurigae> man...I have a board here that would make an awesome test/play controller board if I only had schematics and pinouts.
[12:26:01] <WormFood> Reverse engineer it ;)
[12:27:00] <Lambda_Aurigae> powerpc processor, 1GB of ram, lots of i/o, 2 cyclone II FPGAs, sata interface, com port, ethernet port, 4 usb ports.
[12:27:16] <Lambda_Aurigae> central processor board for a xerox copier.
[12:27:27] <WormFood> interesting
[12:27:33] <WormFood> sounds cool
[12:27:47] <Lambda_Aurigae> hell, it even has a PCI edge connector on one side for connecting a modem.
[12:28:47] <Lambda_Aurigae> the fucker even runs linux.
[12:29:10] <WormFood> wow. Then it should be fairly straight forward to develop for it.
[12:29:33] <Lambda_Aurigae> for the processor side, yeah.
[12:29:40] <Lambda_Aurigae> not sure about for the FPGAs though.
[12:29:52] <Lambda_Aurigae> that would take some serious reverse engineering.
[12:29:55] <WormFood> You can probably program those to do whatever you want.
[12:30:06] <Lambda_Aurigae> yeah..just gotta figure out how they are connected.
[12:30:26] <WormFood> That's the tricky part.
[12:30:32] <WormFood> Gotta pic of the board?
[12:31:10] <Lambda_Aurigae> just a min.
[12:33:02] <Lambda_Aurigae> gotta email them to myself.
[12:33:18] <WormFood> heh
[12:33:19] <Lambda_Aurigae> phone is being slow.
[12:33:41] <WormFood> I use airdroid to get pictures off my phone. So freakin' easy, and fast.
[12:34:39] <Lambda_Aurigae> sending from my phone in my hand to my computer at home,,,30 miles away..
[12:34:46] <Lambda_Aurigae> I'm remoted into my home PC here.
[12:35:24] <Lambda_Aurigae> and phone was on 1x,,,not even 3g..
[12:35:58] <WormFood> email is inefficient for pictures, because it increases their size.
[12:36:25] <WormFood> And compounding that, is an already slow connection. There needs to be a better way of getting pictures off your phone.
[12:36:54] <WormFood> Perhaps TeamViewer would do it more efficiently (it has a file transfer function, and runs on iphone and android)
[12:37:14] <Lambda_Aurigae> using teamviewer to connect to home computer.
[12:37:23] <Lambda_Aurigae> but phone has horrible connection in this building.
[12:37:46] <WormFood> if you have team viewer on your phone, you should be able to upload the files directly to your computer, from your phone.
[12:37:57] <Lambda_Aurigae> yeah....but connection is still slow.
[12:38:01] <Lambda_Aurigae> email got sent finally.
[12:38:07] <WormFood> But, it may be faster than email
[12:38:35] <WormFood> And the file transfer mode, doesn't share out the screen, so lower bandwidth there.
[12:40:06] <Lambda_Aurigae> and, of course, the images didn't go...dangit.
[12:40:25] <WormFood> meh. don't worry about it. Do it when you get home.
[12:42:08] <Lambda_Aurigae> it's bugging me now...hehe
[12:42:19] <WormFood> I know the feeling.
[12:44:09] <Lambda_Aurigae> I got another 25 minutes of lunch to futz with it...hehe
[12:47:49] <Lambda_Aurigae> went for a walk around the building..finally sent.
[12:48:23] <Lambda_Aurigae> http://192.171.217.250/pics/xerox-motherboard/
[12:50:15] <Lambda_Aurigae> http://192.171.217.250/pics/here-is-your-problem-it-was-unplugged.jpg xerox copier tech of the year.
[12:56:03] <Lambda_Aurigae> not the best pics of that motherboard but they will do.
[12:56:31] <Lambda_Aurigae> that is out of a xerox workcentre 5755.
[12:56:49] <Lambda_Aurigae> about 6 year old technology.
[13:02:50] <jben> Lambda_Aurigae: it is, but it not nornal
[13:04:42] <Lambda_Aurigae> huh, wha? Normal? What's not normal? Open collector outputs? Happens all the time.
[13:05:01] <Lambda_Aurigae> I've seen them on PIC, and AVR both.
[13:05:35] <Lambda_Aurigae> or, you saying I'm not normal? In which case, I agree.
[13:08:14] <jben> Lambda_Aurigae: no that is not normal, is to have Vcc=3.3V, and to have 2.7V on the pin
[13:10:19] <jben> (with a pull-up to Vcc)
[13:10:33] <Lambda_Aurigae> 10K ohm pullup? you won't get the full voltage I suspect.
[13:11:11] <Lambda_Aurigae> ok..I must off to worky be going as lunchy is over now.
[13:12:40] <jben> 10k is small, this is the minimum value allowed by the datasheet
[13:38:24] <WormFood> Lambda_Aurigae, looks like a nice board, but would be difficult to map out the FPGAs due to the design of the board.
[14:28:23] <Sculptor> game over. microchip won
[14:28:32] <WormFood> Now what?
[14:28:43] <WormFood> Are they gonna kill the AVR family? ;)
[14:28:52] <Sculptor> eventually
[14:29:00] <WormFood> You really think so?
[14:29:05] <WormFood> That'd be sad if they do.
[14:29:09] <Sculptor> in 10 years maybe
[14:29:15] <WormFood> We'll see.
[14:29:40] <Sculptor> maybe we see a multicore mcu soon
[14:29:50] <WormFood> in the AVR family?
[14:29:57] <Sculptor> are there any
[14:30:05] <WormFood> not that I'm aware of
[14:30:12] <Sculptor> sure, why not
[14:30:16] <WormFood> Although, using multiple AVR isn't hard
[14:30:22] <Sculptor> microchip is not a multicore champion either
[14:30:35] <Sculptor> but other competitors are
[14:31:23] <WormFood> have you seen any multi-core 8-bit CPUs?
[14:32:22] <Sculptor> why not 32-bit mcu
[14:32:33] <WormFood> they have them
[14:32:45] <WormFood> why are we still using 8-bit machines, when we have 16 and 32-bit machines?
[14:33:07] <Sculptor> because it'd be very expensive to replace them all
[14:33:10] <WormFood> Because they work. They're low cost. And they're reliable. Easy to program using asm.
[14:33:22] <WormFood> Why don't they stop making them?
[14:33:50] <WormFood> I'm not talking about replacing them. Why don't they kill them off? Why are they still developing new 8-bit CPUs?
[14:33:58] <N1njaneer> A lot of the newer 32-bit processors cost LESS than the 8-bit.
[14:34:19] <N1njaneer> Because of newer fab technologies and die-shrink.
[14:34:19] <WormFood> But, do they use less power?
[14:34:24] <Sculptor> sure
[14:34:27] <N1njaneer> Yep.
[14:34:39] <WormFood> I'm sure it depends on various things
[14:35:11] <WormFood> I don't think you can get a 32-bit cpu, that uses less power than an 8-bit cpu, within the same technology family (newer techniques, smaller traces, etc)
[14:36:00] <N1njaneer> Sure you can. Just look at Atmel's Cortex M0+ offerings agaist most of the AVR series.
[14:36:16] <WormFood> If you want to claim newer 32-bit CPUs use less power than older 8-bit CPUs, then you're not saying anything special there, because you're not comparing the same things.
[14:36:18] <N1njaneer> Most of the SAMDxx parts cost less than most ATMEGAs
[14:36:36] <N1njaneer> Total power usage is total power usage. Look at the datasheets :)
[14:36:43] <WormFood> But not the smaller chips.
[14:37:08] <N1njaneer> MSP430 was temporarily the winner for lower-power stuff, but then Atmel and others wound up scooping them on a lot of the newer stuff.
[14:37:12] <WormFood> so, SOME 32-bit MCUs cost less than SOME 8-bit MCUs...big deal. That is no surprise to me.
[14:37:29] <N1njaneer> Depends on your application, needs, and price-point requirements, if any.
[14:37:38] <N1njaneer> That's why there's a palette of options.
[14:38:02] <WormFood> why are 32-bit CPUs available in multiple cores, but not 8-bit CPUs?
[14:38:18] <N1njaneer> But obviously 8-bit designs from 10 years ago are generally going to be surpassed by newer chips.
[14:38:46] <N1njaneer> Because there's generally no need for such things. You either use multiple 8-bit chips, or you step up to a more capable processor.
[14:38:56] <WormFood> Because we don't need SMP on 8-bit machines. If we need more power, we get a better MCUs...like 32-bit. 8-bit is low end. SMP is not low end.
[14:38:58] <Sculptor> microchip programming specification is a mess
[14:39:09] <Sculptor> in circuit serial programming
[14:39:33] <N1njaneer> It will be interesting to see what comes of this Atmel/Microchip merging
[14:40:29] <N1njaneer> It's why I'm glad I'm doing quite a but of stuff with ARM Cortex right now, because if the whole Atmel thing goes to crap at least there's a dozen other manufacturers to transfer right over to :)
[14:40:34] <N1njaneer> +bit of
[14:43:13] <N1njaneer> Anyone watched the videos of a Mydata My600 paste-jet in action? Completely insane!
https://www.youtube.com/watch?v=DlUk_m1cKEw Dispensing starts at about 0:30
[14:48:53] <WormFood> AVRs have been extremely popular, I think because they're fairly easy to learn how to program. Feature rich. Fast. And uniform. Once you learn one, nearly everything you learn on one AVR, is directly applicable to any other AVR
[14:52:25] <Jartza> eveninG
[14:54:08] <x29a> WormFood: with the new owner, lets see where the journey goes
[14:54:31] <WormFood> It seems likely they'd kill off the AVR family
[15:03:13] <Sculptor> i trust most people here is not a fan of tarduino
[15:03:25] <Sculptor> are not
[15:10:37] <LeoNerd> Ijust remembered I can cheat with my decoupling caps. TTH chips, 0603 SMD caps. I'll just mount them on the reverse of the board, under the power pins of the respective chips
[15:10:43] <LeoNerd> Zero surface area wasted :)
[15:20:08] <N1njaneer> I usually try to always keep everything on one side of the board - easier to assemble. :)
[15:28:35] <Sculptor> what are you working on LeoNerd
[15:31:04] <x29a> i want to drive an IRF3710 on an output of a tiny26, now to have the mosfet be off when the avr is booting or something, i want to put in a pulldown (as suggested here:
https://electronics.stackexchange.com/questions/60427/calculating-the-pulldown-resistance-for-a-given-mosfets-gate) - i dont get the explanation there, does it really matter for low frequencies?
[15:31:56] <x29a> so i get a resistor in series (connecting PINA and the mosfet) will limit the current, additionally one resistor between PINA and GND, right?
[15:33:21] <RikusW> between gate and ground
[15:34:39] <RikusW> also be sure that the gate volts is high enough if you use high current
[15:37:00] <x29a> high drain-source current that is?
[15:37:13] <x29a> so that it is fully open?
[15:38:12] <LeoNerd> Sculptor: I'm calling it "happysad" buttons. 4 big pushbuttons mounted to a little data logger board. SD card, RTC, ATmega328P. Battery powered. It's for receiving "instant feedback" at conference panels, talks, etc..
[15:38:33] <Sculptor> ds3231
[15:38:41] <LeoNerd> PCF8563
[15:38:45] <Sculptor> ok
[15:38:51] <LeoNerd> I dno't need the superhigh timing accuracy of the 3241
[15:38:55] <LeoNerd> 3231
[15:39:00] <N1njaneer> x29a: Since it's a MOSFET you probably don't need the series resistor because there is no significant current flow to the base as there is with a standard transistor. The AVR will be in tri-state when it starts up, so a simple high-value pull-down resistor should work fine.
[15:39:27] <Sculptor> instante feedback implies networking
[15:39:29] <x29a> N1njaneer: high value? if read between 1k, 10k, 100k
[15:39:31] <RikusW> x29a: generally you want the mosfet to be fully on or fully off
[15:39:34] <Sculptor> instant
[15:39:41] <N1njaneer> But as Rikus said, you need to ensure the voltage is high enough to make sure it's switched fully on.
[15:39:49] <N1njaneer> x29a: I would probably use a 100k minimum.
[15:39:56] <LeoNerd> It's not "instant"; but it's within an hour or so. Rather than the few-weeks we normally get with email / web forms people fill in later
[15:39:56] <x29a> minimum, ok wow
[15:40:25] <N1njaneer> x29a: Because you don't want excess current-flow from the AVR through that pull-down resistor when in the ON state. It's basically a voltage divider. :)
[15:40:54] <x29a> so depending on the input voltage of the AVR, the output voltage will be, right?
[15:40:54] <RikusW> N1njaneer: a series resistor might offer some protection in case of catastrophic mosfet failure, eg S to G
[15:41:09] <x29a> if i drove the AVR with 3.3V, itd be 3.3V, same for 5V?
[15:41:25] <RikusW> AVR max vcc is 5V
[15:41:35] <RikusW> some mosfets needs 10 to 15 V
[15:41:35] <N1njaneer> A long time ago I made a circuit that used 1K resistors as pull-ups on a bank of DIP switches and wondered why my circuit would pull rediculous amounts of current when all the DIP switches were set to zero XD
[15:42:11] <N1njaneer> RikusW: Very true for protection of the AVR, though if the whole thing fries, best to just put new parts in anyways I say :D
[15:42:24] <RikusW> heh
[15:42:37] <Sculptor> 1k pull-ups
[15:42:46] <RikusW> I've seen my share of exploded transistors while repairing PC smps
[15:42:51] <Sculptor> N1njaneer, maybe they were shorted
[15:43:19] <N1njaneer> x29a: You need to see what the specs are on the IRF3710 versus the load you are switching. You MIGHT need to put in another transistor and higher voltage to bootstrap the MOSFET gate with the AVR's control.
[15:44:00] <N1njaneer> Sculptor: Well, when you have 16 DIP switches set to zero that was basically 16 x 1K resistors in parallel, which was not good! 10K or 100K definately better there :D
[15:44:14] <Sculptor> yes, shorted to gnd
[15:45:01] <N1njaneer> Or optionally internal AVR pull-ups, however there are a LOT of subtle gotchas on that regarding timing if you don't leave them all engaged. Which if you are pulling ALL of them to ground will cause the micro to heat up a noticable amount from current consumption.
[15:45:31] <N1njaneer> Always best to use EXTERNAL pull-ups with high values if you need to attach a bunch of lines to the micro that might all get yanked to ground, as in the case with DIP banks.
[15:45:49] <RikusW> good tip
[15:45:58] * RikusW didn't think of it like that
[15:46:57] <RikusW> x29a: at what frequency will be mosfet be switching ? low or into kHz ?
[15:47:02] <N1njaneer> Or else use internal pull-ups but only turn them on before periodic readings. Make ABSOLUTELY SURE there are a couple dozen microseconds of time or more between turning on the pull-ups and reading the port, as you can get REALLY whacky metastability issues that are hard as hell to track down.
[15:47:52] <x29a> the voltage i need to apply on the gate for it to fully open is "gate threshold voltage" in the datasheet? or is this when it starts to open?
[15:47:54] <N1njaneer> And only poll it infrequently. If it's DIP switches, they probably won't be adjusted often, so even once or twice a second is usually acceptable. Or else latch the condition on start-up and require a power-cycle to take the new settings. :)
[15:48:02] <x29a> RikusW: sub kHz
[15:48:57] <RikusW> N1njaneer: less components and low power, sounds good
[15:49:29] <Sculptor> N1njaneer, sorry, was playing tagpro (lost the game)
[15:49:33] <N1njaneer> x29a: You need to make sure the voltage is high enough to push it in to complete saturation for the voltage/current running through the MOSFET that you are attemping to switch, else you have the MOSFET functioning as effectively a very non-linear resistor, and as such it will dissapate power. :)
[15:50:09] <x29a> ok, im looking at the Vgs to I diagram now
[15:50:17] <RikusW> x29a: just saying, driving a mosfet at higher frequencies needs a proper gate drive circuit because higher currents due to gate capacitance
[15:50:17] <Sculptor> N1njaneer, well, if you want to sense DIP switches, sacrifice another GPIO to provide power for htem, and set it high only during the measurements, and you'll hae ultra low power consumption
[15:50:51] <x29a> RikusW: understood, thanks
[15:50:55] <RikusW> if simply driving a relay no need to worry about that
[15:50:57] <x29a> lets say 200Hz
[15:51:09] <x29a> im driving a solenoid
[15:51:12] <RikusW> driving a motor ?
[15:51:14] <RikusW> ah
[15:51:34] <x29a> something like
https://electronics.stackexchange.com/questions/108113/control-12-solenoids-with-a-raspberry-pi
[15:51:35] <RikusW> At what current ?
[15:51:44] <x29a> ~1A
[15:51:52] <x29a> for very short times
[15:52:16] <N1njaneer> Sculptor: Yes, but in that case you generally want to use an NPN connecting the common bonding on the DIPs to ground and switch that for Reasons. I do that on all of our really low power parts. Same applicability to the bottom of a voltage divider used for reading battery level.
[15:54:05] <RikusW> x29a: look at your Rds(on) and Vds(on)
[15:54:09] <N1njaneer> Because there's nothing worse than a voltage-divider which constantly leaks current from the batteries it's trying to measure!
[15:55:19] <Sculptor> aye
[15:55:41] <Sculptor> well you need to compensate for the Vcesat
[15:56:38] <x29a> RikusW: what does Rds(on) tell me? i didnt find Vds(on) except for in the "conditions" column in the datasheet
[15:57:05] <RikusW> Resistance from D to S
[15:57:51] <x29a> do i need to provide that for it to be on, or is it acting like a resistance of that value when its on (and on beeing: fully switched?)
[15:58:15] <x29a> sorry, im new to this, and the idea is creeping up on me, that the parts i have are not the right ones
[15:58:18] <N1njaneer> Sculptor: Yep, so you set your resistor values as such and/or compensate on the software side. Or use a MOSFET. :D
[15:59:02] <Sculptor> or sense Vbatt after a high side mosfet switch that provides power for the device when it's 'on'
[15:59:12] <N1njaneer> x29a: The MOSFET should present nearly zero resistance when it's fully switched on. The trick is making sure it gets there completely for your load. :)
[16:00:08] <RikusW> x29a:
http://www.irf.com/product-info/datasheets/data/irf3710.pdf
[16:00:15] <x29a> i have that open
[16:00:21] <N1njaneer> Sculptor: Yes, but then it's high-side and may be tricky to get enough voltage to make the gate happy XD
[16:00:50] <RikusW> x29a: look at the "Typical Output Characteristics" graphs
[16:01:40] <x29a> RikusW: which of them? i did look at Fig3
[16:02:06] <RikusW> Fig1 and 2
[16:02:10] <x29a> from that i concluded, i need at least > 3.5V on gate to be able to switch 1A drain/source
[16:03:14] <RikusW> You'll lose about 1W on the mosfet if continuously on
[16:03:37] <x29a> RikusW: ok, so the bold lowest line marked with 3.5 says, at 3.5V of gate/gnd, i can pull 2A at 10V?
[16:03:39] <x29a> aka 20W
[16:03:47] <RikusW> there are low gate V mosfets available
[16:04:46] <RikusW> it says that if 1A flows that Vds will be 0.7V, and 1x.7=0.7W loss
[16:05:16] <RikusW> Do you already have this mosfet ?
[16:05:30] <x29a> yes
[16:05:42] <x29a> but buying a different one is also no problem
[16:05:50] <RikusW> 5V should be ok
[16:06:53] <x29a> what does Vds mean? i thought it is switching fully open?
[16:07:01] <x29a> e.g. for the solenoids, they work with 12V
[16:07:13] <RikusW> Volts from drain to source
[16:07:15] <Sculptor> 1983 called. it wants 5V back
[16:07:21] <x29a> does that mean, 0.7V are substracted "in" the mosfet?
[16:07:44] <x29a> RikusW: voltage drop in the mosfet?
[16:07:45] <RikusW> 0.7V drop across the mosfet
[16:07:48] <x29a> i see
[16:08:06] <RikusW> due to Rds(on)
[16:08:12] <N1njaneer> x29a: Yes, so as RikusW said 0.7V drop * 1A = 0.7W power loss in the MOSFET
[16:08:14] <x29a> thanks a lot, im starting to get a clearer picture
[16:08:20] <RikusW> lower gate V leads to higher Rds(on)
[16:08:23] <N1njaneer> So it heats up because the power has to go somewhere
[16:08:43] <x29a> 0.7W is quite some power :/
[16:09:09] <x29a> ok, for constant on
[16:09:13] <RikusW> if the solenoid is on for only 10% of the time it will be 70mW
[16:09:21] <x29a> oh no, it says 20µs pulse width
[16:09:55] <RikusW> 5V looks significantly better than 3v5
[16:10:14] <x29a> roger, alternative is to look for a mosfet that turns on at lower voltages
[16:10:51] <x29a> or other way: has lower Vds at lower Vgs (same Ids)
[16:10:58] <x29a> any recommendation?
[16:11:36] <RikusW> Do you have any reason the AVR needs to run below 5V ?
[16:12:05] <x29a> the PSU is 3.3v
[16:12:23] <x29a> i guess i could take the 12V and an 7805 or something
[16:12:59] <RikusW> do you have access to the 12V supply of the coil ?
[16:13:00] <Sculptor> x29a, let's party like it's 1983
[16:13:12] <x29a> RikusW: yes
[16:13:19] <x29a> Sculptor: 7805 are also outdated?
[16:13:28] <x29a> damn, its been a while
[16:13:32] <RikusW> 7805 can work
[16:13:41] <x29a> Sculptor: so i have this tube....
[16:13:44] <x29a> jk jk
[16:14:20] * RikusW got some 555's lying around
[16:14:39] <x29a> timer ALL the circuits!
[16:15:05] <Sculptor> look, AA121
[16:15:12] <RikusW> x29a: you could make a drive circuit using a pnp and npn transistor and some resistors
[16:15:31] <RikusW> fet - pnp - npn - avr
[16:15:58] <x29a> ok, ill let that be a different project
[16:16:14] <RikusW> 7805 seems easiest to me though
[16:16:52] <RikusW> and you do have one OVERKILL mosfet that can tak 57A :-P
[16:17:06] <N1njaneer> Rikus: If he has access to the 12V rail, could add another transistor to bootstrap the gate control boltage and go all Darlington-like? :)
[16:17:18] <N1njaneer> Oops, sorry - scroll stuck :)
[16:17:23] <N1njaneer> Didn't see the newer text.
[16:17:25] <RikusW> heh
[16:18:00] <x29a> RikusW: in general, if i look for "smaller" mosfet, will the Vds be smaller for smaller Vgs as well?
[16:18:34] <RikusW> not necessarily
[16:18:44] <x29a> ok, so ill have to study the datasheet
[16:19:02] <RikusW> there are special low Vgs ones available though
[16:19:37] <x29a> the gate pulldown is still at 100k? regardless of driving the mosfet with 3.3V or 5V? and also knowing the load will be 12V/1A aka 12W?
[16:20:26] <RikusW> pulldown is just to ensure the default state is off
[16:22:10] <x29a> is this then called "base resistor"?
[16:22:21] <RikusW> no
[16:24:41] <RikusW> x29a: have a look at PMV56XN
[16:26:22] <x29a> nice, Vds < 0.25V
[16:26:27] <x29a> RikusW: thanks
[16:26:47] <nuxil> what u making?
[16:27:04] <x29a> at Vgs=1.5V that is
[16:27:14] <x29a> nuxil: im driving a solenoid
[16:27:46] <x29a> as part of an instrument, so it should actually just really shortly be turned on
[16:29:08] <RikusW> x29a: can you solder SMD SOT23 ?
[16:29:49] <x29a> not knowing what it is, id say no
[16:30:22] <x29a> ah that doesnt look too hard
[16:30:54] <nuxil> x29a, is the IRF3710 a logic level mosfet? if not get some bcm 547 or something to drive it. also you dont really need a LM7805 or other regulator for you chip.. just use a zenerdiode 1w 5.1 V :p
[16:31:15] <RikusW> the part is tiny 3x1.4mm
[16:31:37] <Jartza> https://drive.google.com/file/d/0B2dTzW9TMeBxWXNmQzZYSUhycEU/view
[16:31:52] <Jartza> there's sot23 on that red breakout
[16:32:07] <x29a> i found a 1:1 comparison paper
[16:33:07] <nuxil> i have my atiny85 hooked up to some bcm547 which drives some irf530 mosfets :D
[16:33:16] <x29a> nuxil: Vgs 2-4V, the bcm to drive the mosfet? yeah, somebody suggested something like that
[17:16:19] <LeoNerd> Well,... Too late now, I'm committed to copper. :)
[17:16:22] <LeoNerd> .. on one board, anyway
[17:19:51] <N1njaneer> Awww
[17:20:46] <LeoNerd> Means I have a week or so to play around with the software until it arrives, and see if Ican get some nice reliable code by the time it comes
[18:21:18] * N1njaneer digs through old files to match to stencils
[18:24:15] <LeoNerd> Ohoh.. did you see my first stencilling the other day?
[18:24:42] <N1njaneer> I think so! Worked well?
[18:25:06] <LeoNerd> Yup
