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[00:05:11] <koolatron1> Nevermind. I'll just use the PSTR macro.
[00:43:45] <zMegaMan> Goodday, I have a question that I hope can be relatively quickly answered. I have a device that powers on by pulling its Power_Pin Low for one second. On designs for using the device a FET is connect to the Power Pin to help pull the pin low. My question is why do I need to use a FET, Can't I just directly connect it to an INPUT Pin on the Atmega, and drive the Pin Mode Low and then back to INPUT, would that not have the same effect?
[00:44:59] <zMegaMan> Because in INPUT mode, Atmega has low impedance pins, so it is as if it is floating, and the internal pull-up of the device will pull it high, and when set to pull low (to ground) it is the same as activating the FET.
[00:45:16] <Casper> zMegaMan: maybe
[00:45:33] <zMegaMan> And both devices operate on the same logic level.
[00:45:40] <Casper> is that pin voltage equal or less than the avr supply?
[00:46:03] <Casper> is the current to that pin less than 10-40mA?
[00:46:27] <Casper> (10 being your design goal, 40 being the maximum that the avr handle)
[00:46:47] <zMegaMan> Casper yes, on the datasheet it says the maximum current from the power pin is 15mA, The FET would tie it directly to ground in anycase.
[00:46:48] <Casper> and what is the active low voltage of your device?
[00:47:27] <zMegaMan> Casper there you need to help me out a bit. What do you mean by active low voltage?
[00:47:57] <Casper> what voltage is considered to be a low on your device?
[00:47:58] <zMegaMan> I have tried this it works, I am just worried that in the long run something might break.
[00:48:07] <Casper> nothing output a perfect 0V
[00:48:20] <zMegaMan> Casper, on the datasheet it says pull to ground for the Device (which is a GSM module).
[00:48:36] <Casper> yes, but check the level
[00:48:41] <Casper> it will be in one of the tables
[00:49:01] <zMegaMan> Okay I understand you mean I should compare the LOW range on the Atmega with the LOW range on the GSM Module?
[00:49:08] <zMegaMan> I think both are 0 - 0.7
[00:49:10] <Casper> basically, what voltage is considered to be a low? 1V and less? or 0.3V or less?
[00:49:38] <zMegaMan> Casper, that is a good point to consider.
[00:49:58] <Casper> if the voltage match what the avr is able to sink it to, and the current is within the avr limit, and the high voltage is within the avr supply range, then it should work
[00:49:59] <zMegaMan> Say they are in the correct ranges, are there any other implications to doing it like that?
[00:51:44] <zMegaMan> The reason I ask is it seems like standard practice to always use the FET setup when something has to be pulled LOW, and it just doesn't make sense to me if the devices operate on same logic level.
[00:53:15] <Casper> your standard practice is from the datasheet? or from real world application?
[00:55:50] <zMegaMan> from datasheet, and many sample schematics I have seen.
[00:56:21] <Casper> the datasheet tend to not show the proper way but what work and is tested
[00:56:34] <Casper> and tend to make abstraction to what you connect to
[00:56:51] <Casper> and example schematics in the datasheet or in textbook tend to do the same
[04:21:33] <ecilop> datasheets have errata often
[06:15:15] <LeoNerd> So what's anyone think of the recently-announced mega328PB ?
[06:15:27] <LeoNerd> I'm trying to find a good description of what's new
[06:17:44] <LeoNerd> Hmm.. only available in QFP shapes.. no SOIC or heaven-forbid, DIP
[06:20:34] <Lambda_Aurigae> lower power, basically.
[06:20:51] <LeoNerd> Yah.. it doesn't look oooverly different from the previous ones
[06:21:03] <LeoNerd> I'm struggling to see anytihng new, asides from the unique device ID
[06:27:10] <Lambda_Aurigae> better calibration on the internal oscillator too.
[06:28:51] <Lambda_Aurigae> http://money.cnn.com/news/newsfeeds/articles/prnewswire/SF62393.htm
[06:29:30] <Lambda_Aurigae> new features: unique id, improved accurace of internal oscillator for usart comms, improved accuracy of internal voltage reference for better ADC results.
[06:29:59] <LeoNerd> Ahright..
[06:30:15] <Lambda_Aurigae> pretty much it.
[06:30:21] <LeoNerd> I suppose, given the small change of name (putting the 'B' suffix) there wasn't going to be much new fancy stuff
[06:30:27] <Lambda_Aurigae> I posted that link in here a couple days ago
[06:30:28] <LeoNerd> Not like the tiny84 -> tiny841
[06:30:50] <Lambda_Aurigae> yeah...just B revision of the die basically.
[06:30:51] <LeoNerd> That's practically a whole new chip, with the same pins
[06:31:22] <Lambda_Aurigae> I just wish they would kick the speed up and add USB to a dip package chip.
[06:31:33] <Lambda_Aurigae> 40MHz would rock.
[06:32:12] <LeoNerd> I'm slowly giving up on DIP things, now I've worked out how easily I can do PCBs, combined with building myself up a larger toolset of adapters and so on
[06:32:31] <LeoNerd> I have a SOIC8->DIP8 ZIF socket adapter, so I can put SOIC8s on a breadboard. I have a SOIC14 coming too
[06:32:58] <Lambda_Aurigae> I often work with 3 to 5 kids, teaching them microcontrollers and building things.
[06:33:07] <Lambda_Aurigae> those adapters can get pricy.
[06:33:24] <LeoNerd> Ahhhh
[06:33:31] <LeoNerd> Yes; different environment to me then
[06:34:10] <LeoNerd> Though it's only the sockets that are expensive. You can get those little solderable SOIC->DIP adapter boards really cheaply
[06:34:20] <LeoNerd> They'd let you put a tiny841 on a breadboard, say. BotThoughts have one
[06:34:25] <Lambda_Aurigae> then you have to solder them.
[06:34:52] <LeoNerd> Well, -someone- does. If you order the one off botthoughts it comes with the chip already on
[06:35:06] <Lambda_Aurigae> then you gotta pay for it!
[06:35:07] <LeoNerd> Hell for that matter if you want to order parts and ship them to my house I'll solder them up for you and post them on ;)
[06:35:16] <Lambda_Aurigae> most of my AVRs we use we get as free samples.
[06:35:48] <LeoNerd> Mmmm
[06:35:51] <LeoNerd> Well,... I tried ;)
[06:36:42] <Lambda_Aurigae> and mostly atmegas
[06:37:23] <Lambda_Aurigae> for usb stuff we have been playing with the pic18f45j50...able to do usb with that without a crystal actually...and it's in dip package.
[06:37:39] <Lambda_Aurigae> 3 resistors and 1 capacitor and the chip...add power and a usb cable.
[06:38:21] <LeoNerd> I have mixed opinions of USB lately. Most simple things I just stick a PL2302 cable on it. You can get those for about GBP1
[06:38:24] <Lambda_Aurigae> it has a pll that can sync the internal rc oscillator to the usb clock..
[06:38:33] <LeoNerd> USB A plug on one end, cable with 4 pins on the other, VCC GND Tx Rx
[06:38:42] <LeoNerd> It's good enough for CDC things anyway
[06:38:50] <Lambda_Aurigae> yup.
[06:38:55] <Lambda_Aurigae> have a couple of those.
[06:39:32] <LeoNerd> https://www.tindie.com/products/AtomSoft/tinyledx8/ :) This looks cute
[06:39:45] <LeoNerd> Similar to something I built on stripboard
[06:40:23] <Lambda_Aurigae> I have similar done in through hole.
[06:40:32] <LeoNerd> Yah.. mine is
[06:40:41] <Lambda_Aurigae> I use the rectangular LEDs so they will fit together close.
[06:40:46] <LeoNerd> I usually make everything brought out to a 1x10 stackable header
[06:41:00] <LeoNerd> That way I can shove it on a breadboard and/or put jumper cables in the top
[06:41:35] <Lambda_Aurigae> we built a bunch of them along with soldreless breadboard power supplies and button boards.
[06:42:14] <LeoNerd> Mhmm.. similar to mine
[06:42:17] <LeoNerd> I'll get a photo of them sometime
[06:42:33] <LeoNerd> https://twitter.com/cpan_pevans/status/513825823921803264
[06:42:37] <LeoNerd> I have a button one too
[06:44:23] <Lambda_Aurigae> also made 34 pin idc to breadboard adapters.
[06:44:49] <LeoNerd> Adafruit have some adapters for that
[06:44:52] <Lambda_Aurigae> I have a bunch of older notebooks with serial and parallel ports on them. P-4 class.
[06:45:07] <LeoNerd> 2xN headers that just bend the pins at the bottom, so they can straddle the DIP channel in a breadboard
[06:45:14] <Lambda_Aurigae> put linux on them and use them for programming and interface computers.
[06:45:26] <Lambda_Aurigae> yeah...have done that too.
[06:45:52] <Lambda_Aurigae> for this we made little PCBs, drilled the holes, and soldered headers in.
[06:45:59] <Lambda_Aurigae> was good soldering experience for the kids.
[06:46:10] <Lambda_Aurigae> lots of pins to solder.
[06:46:20] <Lambda_Aurigae> nothing to ruin if it gets overheated.
[06:46:25] <LeoNerd> Mmmm
[06:46:30] <LeoNerd> Until you melt the plastic entirely ;)
[06:46:41] <Lambda_Aurigae> yeah.
[06:46:47] <Lambda_Aurigae> but heck, headers are cheap.
[06:48:11] <Lambda_Aurigae> the 34 pin adapters are great for doing serial and parallel to the breadboard.
[06:48:47] <Lambda_Aurigae> have a roll of 34 wire rainbow cable and a bunch of crimp on 9pin and 25pin idc to dsub ends.
[06:49:20] <Lambda_Aurigae> and stole a bunch of straight idc 34pin connectors from old floppy cables.
[06:50:18] <Lambda_Aurigae> made up nice 24 inch cables which work great to bring the serial and parallel ports around to the side of the computer to the breadboard.
[06:52:04] <Lambda_Aurigae> and v-usb works well with the usb ports on these laptops so a couple of the projects we do are v-usb applications.
[06:53:19] <Lambda_Aurigae> start by making an avr programmer with a 74ls125 on the breadboard,,,do some blinky lights and button inputs,,,add a max233 for serial comms,,,and eventually go on to things like v-usb and advanced comms and interfacing.
[12:39:40] <Rickta59> so i'm new to debug with avr-gdb and debugwire ..
[12:39:51] <Rickta59> i set a breakpoint on an asm statement
[12:39:54] <Rickta59> b *0x80
[12:40:16] <Rickta59> .. it seems like it wiped out the instruction there and replaced it with a break
[12:40:29] <Rickta59> which is fine .. but i thought it did some magic to relocate that
[12:40:41] <Rickta59> so after using delete
[12:40:49] <Rickta59> the instruction didn't get put back to the original
[12:40:55] <Rickta59> is that normal?
[12:41:15] <Rickta59> this is with debugwire / and atmega328p and a dragon
[12:44:26] <Rickta59> and avarice 2.13 and avr-gdb 7.6.50... something
[13:53:11] <bitd> Hello AVR people :-)
[17:03:51] <LeoNerd> I'm considering surface-mount LEDs, rather than 3mm TTH... anyone any thoughts/suggestions?
[17:04:02] <LeoNerd> Is 0603 a bit small for an LED? Should I look larger? Any particular concerns?
[17:05:18] <N1njaneer> Mostly depends on your needs. I suggest going with 0805's or 1206's unless you need tiny, as they'll be easier to solder
[17:05:37] <LeoNerd> I've been soldering 0603 caps/resistors just fine
[17:05:45] <LeoNerd> But I guess an LED has larger visual elements to it
[17:05:56] <N1njaneer> Then you're probably okay. Just be aware they can't take nearly as much heat w/o discoloration
[17:06:11] <N1njaneer> LED die size will be the same in all of those size parts.
[17:06:14] <LeoNerd> Mmm
[17:06:16] <N1njaneer> Just package size difference.
[17:07:11] <LeoNerd> So I guess I should avoid putting them on the grounding plane
[17:07:21] <LeoNerd> Despite having thermals, I still can't manage to solder those very well
[17:15:54] * LeoNerd tries to hit minimum spend limit on Farnell order... pondering if anything else is requird
[17:16:08] <LeoNerd> I might get myself one of those SOIC14 tiny841s just to play with
[17:18:43] <Tom_itx> i got a handfull of those adapter boards i'll likely never use
[17:18:52] <Tom_itx> ppl send when i order boards
[17:20:04] <LeoNerd> Adapter boards?
[18:18:49] <Tom_itx> LeoNerd, yes
[23:52:42] <Romzetron> ls
[23:54:23] <Casper> .
[23:54:26] <Casper> ..