#avr | Logs for 2012-01-24

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[00:27:06] <rue_mohr> http://eds.dyndns.org/~ircjunk/tutorials/elex/fsmflash/main.html
[00:28:04] <rue_mohr> :) yay, it worked
[00:32:19] <ftc1> apparently lamar smith doesn't want people to know what sort of battery you used
[00:33:13] <rue_mohr> :)
[00:33:35] <ftc1> god i hate that guy right now...
[00:33:38] <ftc1> </rant>
[00:34:36] <ftc1> cool project though
[00:34:52] <ftc1> I never had the patience to work with salvaged parts
[00:35:21] <ftc1> well salvaged ICs
[00:35:46] <ftc1> salvaged anything else i have a better time figuring out when its broken
[00:37:56] <theBear> lamar smith ? that black american actor dude ?
[00:38:05] <ziph> How many more points does using salvaged parts get you in the game of pointless projects that could be done with a $40 FPGA board?
[00:38:32] <theBear> if you salvage the fpga and manage to make it program/work, 1000 points, otherwise, not a lot
[00:38:39] <ftc1> theBear: he is the guy who keeps trying to break the internet
[00:39:38] <rue_mohr> there are tonnes of things I could ahve done different there
[00:39:53] <rue_mohr> the goal was to build a rom based FSM that did soemthing
[00:40:01] <rue_mohr> the side effect was getting a POV done
[00:40:27] <ziph> Isn't a CPU largely the same except with an ALU and a richer instruction set? :)
[00:40:38] <rue_mohr> well nobody is mentioning the midding pullup in the background :)
[00:41:07] <CMiYC> a ALU points to stuff
[00:41:14] <CMiYC> a CPU does something with those pointers
[00:41:50] <ziph> Man, that's so.. post modern..
[00:41:59] <rue_mohr> I once worked out a whole computer with state machines, it used a dynamic ram based stae machine that I really wish I still had my drawing for
[00:44:17] <theBear> it is ? does modern mean about 50 years ago ?
[00:45:43] <ftc1> someone made an electromechanical register for thingiverse, still want to see someone use it to make a full electromechanical computer
[00:45:45] <ziph> More like 80-90 years ago if you take the Bauhaus to be the birth of modernism, but I was more poking fun at the nonsensical statements about pointers.
[00:47:07] <ftc1> http://www.thingiverse.com/thing:15346
[00:48:29] <theBear> i know :)
[00:48:51] <theBear> there was a mechanical computer way way back...
[00:49:04] <theBear> holy crap, is that built outta foam ?
[00:49:16] <theBear> oh, printed
[00:57:07] <ftc1> yeah looks like abs plastic
[00:57:43] <ftc1> i am on pla for the winter, abs really stinks up the house if i can't open windows
[01:01:44] <ftc1> hmm now i kinda want to get my hands on one of these curta calculators
[01:01:55] <ftc1> or "math gernade"
[01:02:54] <ftc1> doh: http://www.ebay.com/itm/Curta-Type-II-Calculator-/250974037783?pt=LH_DefaultDomain_0&hash=item3a6f37e717
[01:34:06] <rue_mohr> http://a4.sphotos.ak.fbcdn.net/hphotos-ak-ash4/400821_3150217924279_1530035362_33003719_173190140_n.jpg
[01:34:12] <rue_mohr> is that link accessable?
[01:34:28] <theBear> yup
[01:34:39] <theBear> hehe, and funny
[02:03:27] <Valen> I would feel weird having somebody else clean my shoes
[02:26:20] <rue_mohr> I dont think obama will get back in, he has dirty shoes
[02:26:56] <_abc_> rue_mohr: more dirty or less dirty than those of his competitors?
[02:27:13] <_abc_> Also are their snouts as smeared as his?
[02:43:13] <jnh> I'm currently optimising my code to use less ram - does anyone know how much ram a function pointer takes?
[03:42:20] <karlp> jnh: if you're optimizing for ram usage, and you're not sure how to find out how much a function pointer takes, are you sure you're doing the right thing?
[03:56:24] <dekroning> hi
[03:57:12] <dekroning> are there any boatloads, which can check a file on a web server, in order to update the firmware?
[04:01:42] <specing> dekroning: boatloads? Whats that?
[04:05:55] <karlp> bootloader..
[04:06:20] <dekroning> sorry bootloader indeed, Colloquy on OSX Lion auto corrects, really annoying :)
[04:06:39] <karlp> steve knows how to spell better than you, stop complaining.
[04:07:27] <specing> :D
[04:08:45] <karlp> I don't know of any publicly available ones, but yes, it's been done by many people, and will be done by more, doubtless
[04:09:11] <karlp> it has quite a few variables, how much ram/flash you have, what the hardware is.
[04:09:21] <karlp> what, if any, verification of downloaded files you want to do,
[04:09:29] <karlp> where you intend to store the downloaded images.
[04:24:34] * amee2k idly sticks an isp adapter on atmega
[07:45:56] * blight_ kicks amee2k :p
[07:46:02] <composite> where can i get this? http://search.digikey.com/scripts/dksearch/dksus.dll?vendor=0&keywords=ATAVRMC100
[07:46:07] <composite> if digikey doesn't have it
[07:48:33] <keenerd> Looks like no one has it. Consider yourself lucky, $200 for a stepper eval board is way too much.
[07:49:42] <keenerd> Unless you want to pa an even dumber $500 for it, http://unlimitedmicro.com/p-580511-atavrmc100.aspx
[07:55:55] <Sgt_Lemming> evening all
[08:08:24] <composite> i wanted a BLDC eval board
[08:14:15] <keenerd> I'd make one. $20 microcontroller eval board + normal $50 BLDC controller + $20 brushless motor.
[08:15:11] <Sgt_Lemming> yeah good luck on that
[08:15:33] <Sgt_Lemming> driving brushless motors is a PITA when they have no load, soon as they have any load it become a freaking nightmare
[08:16:44] * amee2k rubs blight_
[08:17:36] <keenerd> I did not say make a driver. He wants a $500 eval board when the parts only cost $100.
[08:18:12] <RikusW> http://www.greenarraychips.com/
[08:19:18] <keenerd> RikusW: You got one? I am still figuring out how to load code into it.
[08:20:28] <RikusW> no do you have one ?
[08:22:21] <rue_bed> did someone say finite state machine?
[08:23:37] <rue_bed> oh that stupid thing
[08:23:57] <rue_bed> 144 useless cpu's on one chip
[08:24:07] <rue_bed> perfect for people who can only code in java
[08:24:46] <RikusW> or if you want to make a bitbanged 10baseT switch ;)
[08:25:34] <rue_bed> maybe, you know the io bus only hits a few of the edge processors tho right?
[08:25:42] <rue_bed> I dont think any of the 'cpus
[08:25:48] <rue_bed> have more than 2 io lines
[08:26:27] <keenerd> rue_bed: Troll harder.
[08:26:39] <rue_bed> I looked at it once
[08:26:49] <rue_bed> I cannot see any use in the world for that chip
[08:27:12] <rue_bed> its worse than an intel multicore
[08:27:36] <rue_bed> someone tied to make a fpga out of cpu's
[08:28:03] <keenerd> RikusW: I have one. It is pretty sweet. It is basically an extremely low power FPGA, and does an awesome job at the low power part.
[08:28:32] <rue_bed> and what can you make it DO?
[08:29:08] <keenerd> For now I'm just trying to do some simple real-time video overlay. Once I get that sorted out, I've got some computer vision algos planned. Each core will track one moving object in the FoV.
[08:29:24] <rue_bed> mhm
[08:29:30] <RikusW> keenerd: isn't it an asic developed by greenarray ?
[08:30:24] <keenerd> RikusW: No, they are legit CPUs, though just barely.
[08:30:33] <rue_bed> do keep us up to date on that eh?
[08:30:37] <RikusW> seems it uses forth.
[08:31:15] <keenerd> rue_bed: I am right now more interested in making my own assembler. Don't want to drink all of Chuck Moore's kool-aid at once.
[08:31:20] <RikusW> I440r would like it ;)
[08:32:00] <RikusW> keenerd: ever made an asm before ?
[08:32:22] <keenerd> Text goes in, bits go out. Nothing complicated ;-)
[08:32:47] <keenerd> And it is a really simple CPU.
[08:33:05] <RikusW> I'd suggest you make an intructions table as an array of structs
[08:33:17] <keenerd> Entire instruction set fits on half a page of paper.
[08:33:21] <RikusW> that data can then be used by both the asm and disasm
[08:34:01] <karlp> he's the same guy behind color forth right?
[08:34:19] <keenerd> Yeah.
[08:34:49] <karlp> ideas might be neat, but I find it hard to believe that I'd comprehend or find any of his work useful, when that's the sort of programming language he advocates.
[08:35:05] <keenerd> Eh.
[08:35:10] <karlp> I guess I'm just not smart enough for regular forth :)
[08:35:19] <RikusW> forth is a bit weird
[08:35:46] <RikusW> but some of its ideas is nice like its stack, but dangerous too
[08:36:00] <keenerd> I just don't like the monolithic-ness of Color Forth. It is like Oberon or Smalltalk. Brilliant system, but you are 100% locked into that stack.
[08:48:04] <amee2k> http://ompldr.org/vY2Zmaw/2012-01-24-153806.jpg << i haz pix of _abc_ 0.0
[08:48:31] <_abc_> caught me there
[08:48:43] <amee2k> >_>
[08:49:18] <amee2k> http://ompldr.org/vY2ZmbQ/2012-01-24-151842.jpg << "halp! raep!"
[08:51:15] <RikusW> amee2k: 43064 ?
[08:54:03] <OndraSter> amee2k, you must be really bored to take these pics lol
[08:57:16] <amee2k> OndraSter: or quite fascinated >_>
[08:57:23] <OndraSter> I'd say bored
[08:57:32] <amee2k> how about a bit of both? :)
[08:57:51] <amee2k> err, wheres rikus gone o.O
[09:02:36] <dekroning> karlp: hey sorry for the long reply "steve knows better how to spell… stop complaining" hehehe :-)
[09:03:06] <dekroning> karlp: ok, I was wondering if there is a maximum size for a bootloader, or if I could use up as many space as I like
[09:04:23] <grummund> use as much as you like so long as it fits :P
[09:06:21] <dekroning> right :-)
[09:06:42] <dekroning> because for a boot loader which downloads it's firmware via HTTP, there are quite some protocol stacks involved :-)
[09:07:46] * grummund guesses this is not avr
[09:08:20] <amee2k> or a ridiculously large one
[09:08:25] <amee2k> or two
[09:08:29] <amee2k> or a dozen
[09:08:32] <amee2k> or...
[09:08:34] * amee2k shuts up
[09:12:41] <Kevin`> dekroning: if you are using the hardware-supported bootloader area, there's a size
[09:12:57] <karlp> that just affects which parts are writable and so on.
[09:13:15] <Kevin`> and your start address
[09:13:16] <amee2k> iirc there are several sizes, selectable by fuse
[09:13:16] <grummund> and the reset vector
[09:13:58] <karlp> dekroning: one thing I've done is have hte main app download via http to a flash card, then reset via wdt, then have the bootloader section look at some shared flags to decided whether to copy the flash card over the old internal flash or not.
[09:14:07] <karlp> so the bootloader didn't have to do any http stuff
[09:14:18] <dekroning> it's actually really nice indeed if it we're possible that this boot loader is not easily overwritten, this is what you guys call hardware-supported boot loader ear aright ?
[09:14:24] <karlp> in the end I decided that an avr was no tthe right choice for this sort of thing.
[09:14:58] <Kevin`> dekroning: read the datasheet...
[09:15:50] <amee2k> how about using two MCUs?
[09:16:01] <grummund> or a ridiculously large one
[09:16:02] <dekroning> karlp: nice :-) so if AVR is not the right choice what is? a dedicated IC that programs the other ?
[09:16:03] <amee2k> one with the HTTP stuff that is set up to flash the other using ISP
[09:16:29] <amee2k> you'd have like a mega2560 with the http and firmware update stuff
[09:16:38] <amee2k> and an attiny13 that does the actual work
[09:16:39] * amee2k runs and hides behind the sofa
[09:16:52] <dekroning> but using two MCU's does that also mean I need to use two ethernet connectors? or what those two IC's use the same ethernet jack?
[09:17:21] <grummund> jeez
[09:17:33] <Kevin`> dekroning: how big is it, anyway
[09:17:35] <amee2k> if your ethernet MAC is SPI you can share it
[09:18:27] <amee2k> the firmware update MCU holds the other one in reset and takes over the SPI bus. then it flashes the other MCU, releases the SPI bus by setting all its pins to high-z and lets go of the reset line
[09:18:31] <dekroning> amee2k: they can share, it just means that when the hardware get's booted up after power reset, the main cpu with actual code just needs to wait and give change for the dedicated boo loader chip to use the ethernet jack?
[09:18:52] <grummund> dekroning: why avr?
[09:18:55] <dekroning> Kevin`: actually i'm not really sure, it will need almost full TCP/IP stack + HTTP libraries
[09:19:12] <amee2k> sounds like you want a medium sized ARM imo
[09:19:52] <grummund> beagle board, raspberry pi, ...
[09:20:02] <grummund> + Linx.
[09:20:09] <grummund> + Linux.
[09:20:21] <amee2k> freertos might do too
[09:20:27] <OndraSter> y not one atmega that simplifies all TCPIP to simple protocol? :P
[09:20:40] <OndraSter> and talk with SPI/UART/... to the remaining part of the board
[09:21:10] <dekroning> grummund: i'm still open to use the chip actually, I would like to use the cheapest one I can use. The only thing this hardware need to do is switch 6 LED's :-)
[09:21:20] <OndraSter> via http?
[09:21:34] <ziph> dekroning: Do you have enough space for two copies of the firmware?
[09:21:59] <dekroning> ziph: well, since i haven't yet choose a chip, I could make sure that I have enough room
[09:22:10] <ziph> dekroning: Or you can put an SPI flash on the side.
[09:22:13] <dekroning> OndraSter: meaning that I would use the ethernet as a bridge to a UART or SPI ?
[09:22:28] <dekroning> ziph: SPI flash not he side meaning?
[09:22:29] <ziph> dekroning: The easiest way to do it is to have your main, normal firmware download the files via HTTP and put them somewhere.
[09:22:32] <OndraSter> opposite, you'd use UART or SPI as a bridge to ethernet
[09:22:44] <dekroning> ziph: yeah indeed
[09:22:59] <ziph> dekroning: Then have a bootloader on the same chip that looks for those files and then upgrades using them if they are newer firmware and their CRC checks out.
[09:23:10] <ziph> dekroning: Then your main firmware just downloads the new firmware and causes a reset.
[09:23:20] <ziph> dekroning: Your bootloader can be tiny and not need any networking.
[09:23:31] <ziph> dekroning: And if the download gets interrupted half way through the hardware is still operational.
[09:23:48] <ziph> dekroning: And by SPI Flash I mean something like the Atmel Dataflash.
[09:23:56] <grummund> better make sure each firmware release is well tested :)
[09:23:59] <dekroning> ziph: interesting
[09:24:16] <dekroning> grummund: not only for bug fixes, but also for new features I want this functionality :)
[09:24:17] <keenerd> Am curious, why do a few blinking LEDs need t obe reflashed?
[09:24:39] <dekroning> keenerd: those LED's are actually optocouplers :)
[09:25:08] <dekroning> keenerd: and i'm driving an external piece of hardware with it, and the combination of the led's that are turned on drive different vendor hardware
[09:25:24] <keenerd> Does it need to stand on its own, away from the network?
[09:26:32] <dekroning> keenerd: i'm control the led's via network
[09:27:16] <dekroning> ziph: indeed like grummund say's then my firmware really can't contain bugs, because if it fails then i'm unable to have it redownload/reflash the hardware
[09:27:20] <dekroning> grummund: now I understand what you said :)
[09:27:24] <keenerd> I am just not seeing why a reflash is needed. It is just a 6 bit data pipe, right?
[09:28:35] <dekroning> keenerd: basically yes, however I'm just afraid for bugs :-) i'm coming from web platform dev, where I can easy patches bugs when needed, now that I want to make hardware, it's really scary to deploy something and have it out there, with no change of easily fixing it
[09:29:13] <OndraSter> hehe
[09:29:14] <OndraSter> FPGA?
[09:29:20] <OndraSter> with loading program from external flash?
[09:29:21] <dekroning> ok cost is also a thing :D
[09:29:38] <keenerd> Remote reflashing is 100x harder to get right than the core project :-)
[09:29:42] <OndraSter> yap
[09:29:47] <grummund> dekroning: what other constraints? physical size? battery power?
[09:29:47] <OndraSter> mostly when it is switching 6 LEDs lol
[09:29:53] <dekroning> keenerd: yeah that's actually true in this case :-)
[09:30:11] <grummund> dekroning: can you use an old PC or laptop?
[09:30:37] <dekroning> grummund: hehehe, ok physical size I would say limited to 10mm x 5mm board, DC power fed (5volts)
[09:30:48] <OndraSter> 10mm * 5mm?
[09:30:51] <OndraSter> that will fit one atmega
[09:30:53] <keenerd> dekroning: I would add some reprogramability, but nothing more than "change password" and "only listen to IP x.x.x.x
[09:30:56] <grummund> :-O
[09:31:07] <dekroning> oops :-) 100mm x 50mm sorry I was thinking cm's
[09:33:44] <dekroning> also I have a question then about, firmware protection, when doing something like this, is it also possible to encrypt your firmware, so other people can't just also use it on their own hardware?
[09:34:16] <OndraSter> dude, are you going to control nuclear silo? :D
[09:34:18] <keenerd> dekroning: http://tuxgraphics.org/electronics/200606/article06061.shtml
[09:34:18] <dekroning> when I think about it, it would require some kind of cryptographic key inside the boot loader, that can then decrypt the firmware after download
[09:34:25] <dekroning> OndraSter: ahahha :)
[09:35:47] <ziph> dekroning: Sounds like you might want to just use an XPort or some Ethernet telemetry board.
[09:36:19] <Sgt_Lemming> CapnKernel, you about?
[09:36:33] <dekroning> ziph: del the price range of the ENC28J60 is something which I like for much, and was use wondering what is possible with boot loaders and these cheap devices
[09:36:42] <dekroning> ziph: maybe indeed i'm asking too much :-)
[09:37:06] <keenerd> That page I linked could be abused to reprogram the AVR. Add one line to the reset pin, and the SPI-slave ethernet chip becomes an ISP host.
[09:37:21] <dekroning> keenerd: reading it now
[09:37:26] <grummund> or an old pc running linux and some homebrew code to read/write the parallel port
[09:37:42] <ziph> dekroning: Have a look at the XPort.
[09:37:44] <amee2k> dekroning: encryption will not ensure integrity or authenticity. what you want is a digital signature
[09:37:44] <OndraSter> I tend to like old laptops with dead screens and such
[09:37:49] <OndraSter> just take the motherboard from it
[09:37:52] <OndraSter> and connect HDD and power supply
[09:38:20] <dekroning> amee2k: like TPM module you mean?
[09:38:31] <amee2k> no, like PGP/GPG
[09:39:00] <amee2k> a digital signature is basically an asymetrically encrypted hash sum
[09:39:28] <ziph> Encryption will ensure integrity and authenticity, digital signatures are used when you don't have full control of the other end.
[09:39:34] <amee2k> it ensures that the download has not been corrupted, and that the firmware update has been approved by the holder of the private key
[09:40:15] <amee2k> ziph: XORing with a static key is a kind of encryption. that most definitely does not ensure integrity
[09:40:42] <amee2k> and it arguably doesn't really ensure authenticity since it is by design susceptible to bit-flipping attacks
[09:40:53] <amee2k> thats how WEP got screwed too lol
[09:41:01] <ziph> No, but putting it through any modern cipher properly will.
[09:41:41] <amee2k> i don't know any cipher that will ensure integrity unless you take care of that separately
[09:42:37] <amee2k> typical block ciphers will happily process everything you shove at them. garbage in, garbage out
[09:42:38] <dekroning> man really interesting stuff this boot loader + http download :-)
[09:43:12] <amee2k> if authenticity is not a concern, then any decent hash sum should suffice i'd say
[09:44:00] <amee2k> not sure if there is a reference implementation for say MD5 on AVR though
[09:44:29] <ziph> amee2k: So you don't consider IPSEC secure?
[09:44:43] <dekroning> is there a common name for these type of bootloaders that download firmware from the web?
[09:44:47] * grummund has done both AES and SSL on an avr :)
[09:44:49] <amee2k> never looked into ipsec. what about it?
[09:44:56] <Sgt_Lemming> dekroning, FUCKING ANNOYING!@
[09:45:07] <dekroning> Sgt_Lemming: haha :-) why? it's freaking awesome stuff :)
[09:45:37] <ziph> amee2k: Ok, you don't consider anything using DH key exchange secure?
[09:45:47] <amee2k> where did i say that?
[09:45:48] <Sgt_Lemming> it can be, it can also be used by assholes to prevent you from being able to hack a product
[09:46:00] <ziph> You said you can't use a cipher for authenticity.
[09:46:02] <Sgt_Lemming> and it's also a great security hole
[09:46:07] <ziph> integrity rather
[09:46:19] <Sgt_Lemming> visa vis the recent major security hole in HP laser printers
[09:46:24] <grummund> dekroning: tftp avr bootloader
[09:46:38] <dekroning> grummund: tftp I need to be on the same LAN no ?
[09:46:46] <grummund> mebbe
[09:46:56] <dekroning> grummund: I'm not sure if tftp is routable
[09:47:00] <amee2k> ziph: the DH exchange is supposed to ensure authenticity because it is supposed to let only the two involved parties know the key. DH is not a cipher, it is a key exchange protocol
[09:47:36] <dekroning> grummund: besides, I would rather use something that goes over HTTP, since that port has high change of not being filtered by firewall
[09:47:39] <OndraSter> another discussion topic: how about running VM on AVR device to allow running code from RAM instead ROM? Ofc with huge speed difference (20MHz host, barely 1MHz user)... :P
[09:47:47] <ziph> amee2k: So if two devices know a secret cipher key, derived through DH or otherwise, they can ensure integrity?
[09:47:50] <OndraSter> plus implement bank-switching on VM level
[09:47:55] <OndraSter> ergo few megabytes of RAM
[09:47:55] <amee2k> and i strongly suspect ipsec uses some other hash algorithm to detect corrupted packets
[09:47:58] <dekroning> Sgt_Lemming: security hole, because other people can upload their own firmware you mean?
[09:48:22] <amee2k> but the naked DES algorithm or whatever they use won't
[09:48:26] <Sgt_Lemming> dekroning, because if there is no auth or key check on that function, yes
[09:48:42] <ziph> So is it the Cipher or the DH that gets the cipher key that ensures integrity?
[09:48:54] <amee2k> lots of ciphers are really just a combination of XOR-ing with a pseudorandom key-stream and permutation
[09:48:55] <dekroning> Sgt_Lemming: that's why I would like to somehow encrypt my firmware
[09:49:09] <amee2k> ziph: neither ensures integrity
[09:49:13] <LoRez> IPSEC signs packets so you know they're authentic
[09:49:18] <dekroning> Sgt_Lemming: and only flash it, if it correctly decrypts the firmware downloaded package
[09:49:51] <ziph> IPSEC signs every packet with PKI?
[09:49:55] <ziph> News to me. :)
[09:50:08] <amee2k> noone said anything about PKI
[09:50:24] <amee2k> you should stop smoking, well, whatever you're smoking. it makes you see things
[09:50:25] <OndraSter> how does have AVR secured their bootloaders?
[09:50:28] <OndraSter> on Dragon 'n such
[09:50:41] <amee2k> probably lock bits
[09:51:03] <LoRez> there's an encrypted bootloader whitepaper at atmel.com
[09:51:23] <amee2k> which makes sense. ciphers are intended to keep the information hidden from evasdropping in transit. not detect in-transit corruption or modification
[09:51:51] <amee2k> check out the XOR bit flipping attack that (in part) killed WEP
[09:51:53] <ziph> amee2k: So how does DH prevent corruption or modification?
[09:52:07] <amee2k> ziph: for the third time, it doesn't
[09:52:08] <LoRez> again, DH is just key exchange.
[09:52:30] <amee2k> read the wikipedia article on dh so you know what it is
[09:53:11] <LoRez> hell, read http://en.wikipedia.org/wiki/Ipsec so you'll stop asking questions that are easily answered.
[09:54:23] <ziph> I'm asking simple questions because amee2k is trying to tell me that some kind of public key signature is required for integrity.
[09:54:41] <amee2k> ...
[09:54:46] <dekroning> thanks all for the info, see you later
[09:54:56] <amee2k> answering it would be much easier if you actually read what i say
[09:57:59] <amee2k> a signature is required for authenticity, which is not the same as integrity. you'll need a checksum to guard against corruption, but as WEP demonstrated hash sum + symmetric cipher does not prevent malicious modification
[09:59:32] <karlp> just means you got the _correct_ malware :)
[09:59:35] <amee2k> if you find a combination of symmetric cipher and hash sum that gives strong protection, DH will indirectly implement a weak form of authentication by keeping the symmetric key hidden from evasdropping
[10:00:14] <grummund> AES-CCM does that
[10:00:25] <amee2k> but some message can still have originated from any party that knows the symmetric key, which is by definition more than one. so it does not give strong authentication
[10:01:04] <amee2k> hence why you have asymetric ciphers so only one party needs to know the private key by design
[10:01:21] <karlp> this is why you normally eveluate whether it's really worth spending weeks on adding security features
[10:01:27] <Kevin`> if you have the user press a button and/or enter a password (for remote updates) before sending the firmware file, you don't have to bother with all that encryption crap to ensure it's clean
[10:01:35] <karlp> because the slightest thing wrong, and it's all a waste of time.
[10:02:16] <amee2k> i never said err dekroning or whoever actually needed cryptographically robust firmware updates
[10:02:55] <amee2k> and you can't really stop someone who has physical access to the device anyway. he can just pop the AVR off the board and put a new, unlocked one in
[10:03:22] <Kevin`> btw, if you plan to use a checksum - and you should, for a network update - you kind of need to store the firmware on some external device, otherwise you have nowhere to put it besides flash
[10:03:52] <Kevin`> unless a broken image in flash is not a problem.. it might not be
[10:03:58] <keenerd> I believe that is why someone else said your FW should be half the size of your flash.
[10:03:59] <ziph> amee2k: grummund just gave an example too, AES-CCM doesn't work?
[10:04:21] <amee2k> you're really not reading what i'm saying, eh?
[10:04:44] <amee2k> do you remember whos project it was that we're talking about?
[10:04:54] <ziph> You've just said that symmetric cryptography is unusable for the application because anyone might have the shared key, right? :)
[10:05:00] * grummund decides not to read what *anyone* is saying :p
[10:05:57] <amee2k> i said it may or may not be suitable for his application because it doesn't ensure integrity on its own. and not very strong authenticity either, for that matter
[10:06:51] <amee2k> so if he wants to limit firmware updates to approved firmware versions only and detect in-transit corruption (accidential or malicious) of the data, then he'll want a signature algorithm instead of a cipher
[10:06:57] <karlp> Kevin`: tcp has checksumming already, why would I want another one?
[10:06:59] <ziph> What does "digital signature" mean?
[10:07:00] <keenerd> Nothing about it made any sense, honestly. If money really was no object, you buy someone else's prefab unit. Plenty of industrial control modules do what he needed.
[10:07:00] <karlp> for tftp, sure,
[10:07:38] <Kevin`> karlp: i've seen various faults in pc or networking hardware cause valid checksums on broken data
[10:07:52] <karlp> what, and _another_ checksum is going to magically fix that?
[10:08:02] <Kevin`> karlp: also, you could, for example, stop sending the firmware half way through because the link went down
[10:08:13] <amee2k> tcp checksums are designed to detect accidential corruption, not malicious one
[10:08:20] <ziph> karlp: Also, have a look at http://web.mit.edu/Saltzer/www/publications/endtoend/endtoend.pdf
[10:08:29] <Kevin`> karlp: a checksum that is computed when building the firmware instead of automatically computed by random networking devices DOES fix it, yes
[10:08:43] <karlp> yeah, ok, true, wasn't thinking like that.
[10:09:16] <Kevin`> that looks like a useful paper
[10:09:18] <amee2k> someone could still put the board on a LAN segment and fake the update server to get unauthorized firmware on the board if you only rely on a plain checksum like TCP does
[10:09:19] * Kevin` adds note
[10:10:50] <Kevin`> amee2k: actually doing that kind of implies they want the unauthorized firmware on the device. unless the update mechanism is automatic, which annoys users anyway ;p
[10:12:15] <amee2k> it doesn't imply that the manufacturer (i.e. the dude whos project it was) desires his users to use unauthorized firmware
[10:12:41] <amee2k> and the unauthorized update doesn't neccesarily have to happen with the knowledge or consent of the rightful owner of the device
[10:12:57] <Kevin`> well, sure, but manufacturers who try to do that fail or drive away customers
[10:13:00] <Kevin`> it's useless to do
[10:13:08] <amee2k> of course they do
[10:13:14] <amee2k> that doesn't mean they can't
[10:13:26] <amee2k> because by now pretty much everyone does something in that general direction
[10:14:28] <Kevin`> it's a waste of development time unless you have a cell phone carrier or similar mandating that you make an effort at it
[10:17:09] <amee2k> of course trying to make sure your users can't use the product is a waste of time
[10:17:35] <amee2k> but money is time, and in this case wasting the developer's time also wastes the customer's money
[10:18:44] <Kevin`> normally that would be a good thing, of course, but if you have the ability to freely waste customer's money, you can instead direct it to profit
[10:19:26] <amee2k> the manufacturer will need to pay the developer either way
[10:19:44] <amee2k> whether he spends his time implementing copy protection of fixing bugs doesn't matter
[10:20:29] * Kevin` scratches head
[10:20:34] <amee2k> what.
[10:21:33] <Kevin`> I didn't see any point in refuting the "doesn't matter" as you know it as well as I do :)
[10:22:14] <ziph> My guess would be that like most of the people coming in here with bizarre ideas and vague questions he won't end up spending any time doing anything. :)
[10:23:36] <amee2k> well, i understood you said if the developer is paid and the money is wasted the developer can do something useful just as well
[10:23:45] <qw> anyone, is this chat for arduino stuff?
[10:24:04] <ziph> Not specifically, but you can try, qw.
[10:24:08] <amee2k> but why can't you bill your customer for trying to make the competition make less money
[10:24:25] <amee2k> qw: if you call it atmega328 instead of arduino, then yes
[10:24:59] <qw> great okay thanks!
[10:25:28] <amee2k> an arduino is really just a usb-to-serial adapter and some headers and an atmega with a custom bootloader so you can update the firmware via usb
[10:25:39] <OndraSter> (we know)
[10:25:45] <amee2k> (some don't)
[10:26:02] <OndraSter> ((oh))
[10:26:10] <amee2k> thats why i said if you don't use the 'A' word, it'll be fine >_>
[10:26:11] <OndraSter> amee2k, still haven't found my NRF24L01s :D
[10:26:18] <amee2k> 0.0
[10:27:13] <amee2k> some people are kinda jealous that with arduinos non EE geeks can have AVRs too
[10:27:43] <OndraSter> heh
[10:28:51] <OndraSter> I am having hard times fitting the main logic board onto about 8x10cm board
[10:28:51] <OndraSter> http://clip2net.com/s/1w8ol
[10:29:04] <OndraSter> probably the 573 could go closer to the memory
[10:29:11] <OndraSter> and rotate it all by 90 degrees
[10:29:15] <OndraSter> ccw
[10:29:34] <OndraSter> since all outputs are on the right (top) side
[10:30:46] <ziph> Put it on a 4 layer board and make it half the size. ;)
[10:31:23] <OndraSter> 4 layer? I'd rather put it on bigger 2 layer
[10:31:24] <OndraSter> price wise :P
[10:32:02] <ziph> Where are you getting boards done where 4 layers are more than twice the price?
[10:32:11] <OndraSter> iteadstudio
[10:35:00] <OndraSter> although this has got fairly got laid out connections too
[10:35:01] <OndraSter> http://clip2net.com/s/1w8tF
[10:36:35] <ziph> Well, ok, but that's probably more them sending the 2 layers off to the dodgiest little PCB house in China and sending the 4 layer boards somewhere reasonable. :)
[10:37:20] <Kevin`> the 4 layer boards from somewhere reasonable will still be more than twice the price of 2 layers at the china house
[10:37:53] <Kevin`> also.. aren't they a chinese company themseves? I suspect they ARE said house
[10:38:23] <ziph> Only if they talk about themselves in the third person.
[10:38:35] <OndraSter> iteadstudio = china :P
[10:38:42] <OndraSter> local prices = 10 times this :(
[10:38:46] <ziph> What I mean is they probably get ultra cheap 2 layer boards from somewhere but get the 4 layer boards done somewhere more expensive.
[10:38:48] <OndraSter> for few pieces production
[10:38:58] <ziph> Where are you?
[10:39:57] <ziph> (Continent wise)
[10:40:12] <OndraSter> middle europe
[10:41:15] <ziph> You can get a 5cm x 5cm board done for $100 USD in Europe? Wouldn't it be more than that? ;)
[10:41:42] <OndraSter> eh
[10:41:49] <OndraSter> 1dm2 = $25
[10:41:59] <OndraSter> you can get ten 1dm2 boards for $25 on iteadstudio
[10:42:03] <OndraSter> (same boards ofc)
[10:42:21] <ziph> 1dm2?
[10:42:26] <OndraSter> ye
[10:42:30] <OndraSter> 1dm squared
[10:42:46] <karlp> I hate dm and dl units.
[10:42:52] <OndraSter> dm?
[10:42:55] <OndraSter> okay
[10:43:00] <OndraSter> 10x10cm2 for $25
[10:43:06] <ziph> People don't use dm outside of Europe, OndraSter. :)
[10:43:07] <OndraSter> + extra paid both layered silkscreen etc
[10:43:15] <karlp> just personal, I know they're commonly used in some parts of the world, I just don't like them as units.
[10:43:17] <OndraSter> ziph, because inch and such are bad :P
[10:43:29] <OndraSter> nobody wants inch except americans
[10:43:31] <ziph> OndraSter: No, they'll either say deci m or cm.
[10:43:32] <karlp> no, most metric countries don't use dm either.
[10:43:33] <OndraSter> ah
[10:43:39] <karlp> mm, cm, m
[10:43:42] <karlp> screw dm
[10:43:45] <ziph> And only very rarely do you hear deci m.
[10:43:46] <karlp> ml and l
[10:43:49] <karlp> screw dm
[10:43:53] <karlp> dl sorry
[10:43:55] <OndraSter> the company that does the boards uses dm2 as main unit
[10:43:57] <OndraSter> so I used that
[10:44:06] <karlp> who's that?
[10:44:11] <OndraSter> pragoboard.cz
[10:44:13] <OndraSter> = czech company
[10:44:20] <OndraSter> just outside the prague (or on the edge)
[10:44:43] <ziph> OndraSter: If US post is comparable you could try laen for small boards.
[10:44:53] <OndraSter> US post?
[10:44:56] <OndraSter> it is not about shipping
[10:45:00] <ziph> Post from the US.
[10:45:01] <karlp> laen's boards are pretty nice really.
[10:45:12] <ziph> The quality will be stellar compared to itead.
[10:45:24] <OndraSter> lean.com?
[10:45:25] <karlp> ondra's boards sound pretty enormous though.
[10:45:27] <OndraSter> laen.com?
[10:45:29] <karlp> dorkbot pdx
[10:45:34] <ziph> And the minimums are much nicer.
[10:45:44] <karlp> http://dorkbotpdx.org/wiki/pcb_order
[10:45:53] <OndraSter> karlp, few are 4x10cm, few are 6x10cm, the rest is something a bit bigger
[10:46:14] <karlp> well, with dorkbot, you're back to making them whatever shape/size you want,
[10:46:19] <karlp> not having to fit in 10x10 panels or anything.
[10:46:21] <OndraSter> shipping for bigger packages from USA = $25
[10:46:45] <ziph> The 4x10 from laen would be $30.
[10:47:01] <karlp> OndraSter: where are you getting that shipping rate from?
[10:47:06] <OndraSter> USPS
[10:47:13] <OndraSter> I remember that it was $25-ish
[10:47:31] <karlp> dorkbot charges $15 for priority, or $5 for standard.
[10:47:32] <OndraSter> ziph, I can get 4x10 from itead for $25... and there is 10 of them
[10:47:32] <karlp> flat rate
[10:47:35] <OndraSter> oh
[10:47:48] <OndraSter> I need ten 6x8 boards
[10:47:48] <OndraSter> cm
[10:48:06] <karlp> I thought you were getting 10 because it was a better deal than 4 :)
[10:48:29] <OndraSter> just on some boards
[10:48:32] <OndraSter> not all of 'em
[10:49:18] <ziph> I like having good quality boards after spending so much time on them, anyhow.
[10:50:14] <OndraSter> iteadstudio does good from what I heard
[10:53:38] <OndraSter> atmega
[10:53:44] <OndraSter> how much for 128a, atmega
[10:53:44] <OndraSter> lol
[10:53:51] <OndraSter> Atmel should provide some sample board layout for their xmem
[10:54:30] <atmega> you mean ATmega128A ?
[10:54:40] <ziph> Tried the evaluation board datasheet?
[10:54:52] <OndraSter> ye atmega
[10:54:59] <OndraSter> (just trying to make fun)
[10:55:42] <OndraSter> there is one, ziph ?
[10:56:05] <atmega> seen on eBay: 10 piece ATmega128A 35.24Euro
[10:56:15] <OndraSter> yap
[10:56:18] <OndraSter> seen that too
[10:56:21] <OndraSter> not bad price IMHO
[10:57:04] <atmega> I use most ATmega644P , ~2.50 eur
[10:57:05] <ziph> OndraSter: No idea.
[10:57:30] <ziph> OndraSter: But that's usually the only place you'll find samples for non RF or very high speed stuff.
[10:57:44] <OndraSter> whoever designed the layout of SRAMs shall die in fire
[10:57:52] <OndraSter> the lower 8bits are designed okay
[10:57:58] <OndraSter> but the remaining 8 address bits ARE MESS
[10:58:04] <OndraSter> random on each side :(
[10:58:49] <atmega> ... then it is heavy to create a layout
[10:59:03] <ziph> IC designers get kickbacks from the multilayer prepreg manufactures.
[10:59:19] <atmega> this could be
[11:01:50] <OndraSter> I can imagine what was going in their heads
[11:02:12] <OndraSter> "so, we have now 8*8 memory. We want to add 9th and 10th addr bit. Where should we put it?"
[11:02:16] <OndraSter> "ofc on the edge"
[11:02:19] <OndraSter> month later
[11:02:26] <OndraSter> "dudes, another four bits"
[11:02:28] <OndraSter> "MAKE THEM RANDOM!"
[11:03:03] <ziph> Oh, some of that goes back to the early days.
[11:03:41] <atmega> is here somebody who etch an own Board?
[11:03:57] <OndraSter> I tried
[11:03:58] <OndraSter> and did
[11:04:23] <OndraSter> ziph, http://clip2net.com/s/1w8Vt
[11:04:26] <OndraSter> isn't it JUST A MESS
[11:04:52] <OndraSter> 16 14 12 7 6 5 4 3 2 1 0... the ending is fine
[11:05:06] <OndraSter> opposite side: 15 - - 13 8 9 11 - 10
[11:05:07] <OndraSter> omg
[11:05:42] <ziph> OndraSter: Yeah, even VDD and VSS are in the worst places possible.
[11:05:46] <atmega> okay, I show you my last universal-board
[11:05:54] <atmega> http://mega8.cwsurf.de/bilder/fastview/Atmega644P_Board_26MHz_min3V.jpg
[11:05:56] <OndraSter> hehe
[11:06:08] <OndraSter> ziph, probably from older, smaller, chips
[11:06:12] <OndraSter> nice, atmega
[11:06:17] <OndraSter> home done?
[11:06:26] <atmega> yes :)
[11:06:28] <OndraSter> ziph, in the name of backward compatibility they had to do it this way
[11:06:30] <OndraSter> cool atmega
[11:06:44] <OndraSter> I was happy to get even .05" spacing without much trouble lol
[11:06:55] <OndraSter> (high pressured lamp)
[11:07:25] <atmega> i use a LaserPrinter
[11:07:38] <OndraSter> and toner transfer?
[11:07:47] <atmega> ja
[11:07:53] <OndraSter> the thing is, you are suck with single sided boards (maybe both sides with a bit of luck)
[11:07:57] <OndraSter> but home done vias = impossible
[11:08:14] <ziph> I can do them.
[11:08:21] <OndraSter> but how much $$
[11:08:41] <ziph> You just said impossible, you didn't say expensive. :)
[11:08:43] <OndraSter> plus no silk screen, no nothing... really just for prototyping
[11:08:45] <OndraSter> haha
[11:08:46] <OndraSter> http://clip2net.com/s/1w8Z7
[11:08:49] <OndraSter> this is my end result
[11:08:50] <OndraSter> for now
[11:08:51] <amee2k> i heard double sided is easy enough if you drill some holes first, then use these for alignment
[11:09:11] <OndraSter> yeah...
[11:09:17] <OndraSter> but not so easy to interconnect it
[11:09:23] <amee2k> vias are bit of a bitch... drill, then thread wire through it and solder
[11:09:24] <atmega> in the next time I will use a PCB service ... because there are a muche vias
[11:09:29] <ziph> The problem with double sided is that laser printers have large distortions across the page.
[11:09:36] <OndraSter> LED printers ftw
[11:09:39] <OndraSter> OKI anyone?
[11:10:08] <ziph> How would that help?
[11:10:17] <atmega> 11 euro, 10 PCBs with 50mmx50mm, from http://www.seeedstudio.com/depot/fusion-pcb-service-p-835.html
[11:10:20] <amee2k> what is all that goop over the mega644 board??
[11:10:50] <ziph> I don't think charging the drum is where the inaccuracies come in, anyhow.
[11:11:06] <OndraSter> ziph, that's probably how the laser rotates
[11:11:08] <OndraSter> but LEDs are stationary
[11:11:24] <OndraSter> $9.90, atmega :)
[11:11:24] <OndraSter> http://iteadstudio.com/store/index.php?main_page=product_info&cPath=19_20&products_id=173&zenid=c3nkuum3ec7ieu5j0uqd69bi64
[11:11:34] <ziph> And you can do vias with punched rivet style things that are filled with solder. Once you punch them in you can desolder the middles out to get a normal open via.
[11:11:44] <atmega> the goop is hotglue
[11:11:53] <OndraSter> plus full etest
[11:12:12] <amee2k> hmmm... seeed wants 80$ for 10 of my LED boards. thats the best per-board price i've seen so far
[11:12:20] <amee2k> too bad i only want 3 >_<
[11:12:30] <OndraSter> amee2k, and iteadstudio?
[11:12:35] <ziph> The distortions aren't per scan line, they're undulating errors that push around 1x1 cm areas.
[11:12:43] <OndraSter> oh ziph
[11:12:44] <atmega> $9,90 + ~4.50$ for transport
[11:12:50] <OndraSter> yeah atmega
[11:12:54] <OndraSter> dunno how is seed with shipping
[11:12:58] <amee2k> itead does boards that large?
[11:13:02] <OndraSter> how large?
[11:13:07] <amee2k> 6x20cm
[11:13:09] <OndraSter> ye
[11:13:17] <OndraSter> they do even over 20x20
[11:13:29] <amee2k> hmm lemme check
[11:13:48] <OndraSter> "In the name of science", I am going to change the pinout of my board
[11:14:27] <theBear> better than doing it for some imaginary daeity
[11:14:43] <amee2k> 65$ for 5 boards
[11:15:03] <amee2k> theBear: thats why i don't buy the imaginary ones anymore
[11:15:10] <amee2k> chinese crap...
[11:15:29] <OndraSter> well itead was referenced here a lot
[11:15:36] <OndraSter> good references
[11:15:42] <amee2k> no, i meant chinese imaginary deities
[11:15:45] <amee2k> >_>
[11:16:26] <OndraSter> oh
[11:17:12] <amee2k> for the next few weeks the project is on hold anyway... flat share is considering moving to a 4-room apartment in the forseeable future and i don't want to order expensive stuff until i have an idea how much money the move will need
[11:17:13] <OndraSter> btw, after talkign with my teacher, we decided to use twice the amount of LED drivers :P
[11:17:30] <OndraSter> so now each LED module will have its own driver... cool isn't it :P
[11:17:39] <amee2k> nice :)
[11:17:43] <OndraSter> that's used 8 boards instead of just 4
[11:17:49] <OndraSter> now I can screw only two lol
[11:24:25] <amee2k> yer a pretty bad ass negotiator when it comes to budget, eh?
[11:24:36] <amee2k> doubling the number of drivers just like that >_>
[11:26:26] <OndraSter> actually, it won't cost me a penny
[11:26:36] <OndraSter> hmm few pennies for 6 caps and 6 resistors
[11:26:38] <OndraSter> but that's it :P
[11:26:42] <OndraSter> I got those drivers for free
[11:26:47] <OndraSter> and few pennies for solder lol
[11:27:14] <amee2k> lol
[11:27:25] <OndraSter> anyway, this project is more than most people do even on university often :(
[11:27:38] <OndraSter> for the bachelor's work
[11:27:45] <OndraSter> (or w/e you call it... after 6 semesters)
[11:28:03] <atmega> are the current driver linear regulated or switching with coil
[11:28:34] <amee2k> from what i understand switching pre-regulator and linear output driver
[11:28:50] <OndraSter> yap
[11:29:16] <OndraSter> there is switching pre-regulator to about 3.3 - 3.5V or w/e will be needed to power the LEDs in the end (remember, red and green have different requirements)
[11:29:21] <OndraSter> for 50mA or so
[11:29:30] <OndraSter> and the rest is dropped on linear regulator inside those ICs
[11:29:47] <atmega> interesting ...
[11:32:04] <atmega> here I found an other tonertransfer-picture: http://mega8.cwsurf.de/bilder/fastview/ATmega8_sockel.jpg
[11:32:35] <OndraSter> yay
[11:32:36] <amee2k> wow, thats pretty nice work :)
[11:32:38] <OndraSter> so I just noticed
[11:32:40] <OndraSter> the TPS54527
[11:32:43] <OndraSter> that I got free samples of
[11:32:51] <OndraSter> are like 5GBP per piece lol
[11:32:59] <amee2k> you dropped it on your pizza and ate it?
[11:33:00] <OndraSter> (I use currency that is simpler to count it)
[11:33:05] <OndraSter> heh
[11:33:16] <OndraSter> 5 free samples of those chips, plus free shipping through fedex
[11:33:33] <amee2k> yeah, i checked it out to see if i could use it for my LED board project. it was 4.something from digikey
[11:33:44] <amee2k> my 34063 is 50 cent lol
[11:33:57] <OndraSter> hehe
[11:34:00] <OndraSter> 34063
[11:34:04] <OndraSter> these have builtin everything
[11:34:11] <OndraSter> except caps and choke
[11:34:43] <atmega> i think his is a good tonertransfer picture: http://mega8.cwsurf.de/bilder/fastview/papier_laminiert_offen50.jpg
[11:34:51] <amee2k> i just need to step down 24V to 5V for the control logic stuff. the 34063's darlington switch sucks at high duty cycle but for this it should work fine
[11:35:20] <amee2k> atmega: what toner type and printer did you use, if i may ask
[11:36:00] <OndraSter> hmm the TPS is only upto 18V... maybe something diff from TI?
[11:36:02] <OndraSter> I <3 TI
[11:36:23] <amee2k> yeah, thats why i didn't switch to the TPS. it doesn't do 24V
[11:39:19] <OndraSter> I suppose that xtal should be as close to the CPU as possible
[11:39:41] <amee2k> yep
[11:40:05] <OndraSter> and no data lines around the package
[11:40:31] <amee2k> and make sure you have good RF ground between MCU, xtal and loading caps
[11:40:41] <amee2k> or they like leaking RF all over the place
[11:48:09] <OndraSter> so smth like this?
[11:48:09] <OndraSter> http://clip2net.com/s/1w9z9
[11:49:17] <amee2k> looks okay. can you put a ground plane under it by chance?
[11:49:49] <amee2k> also, running traces directly on top of each other may not be a stellar idea
[11:50:35] <OndraSter> I can put there ground plane
[11:50:38] <OndraSter> below the cap I presume
[11:50:40] <OndraSter> on both top & bottom?
[11:50:54] <OndraSter> well they are simple GPIOs, not used by any means, just for possible future
[11:53:08] <amee2k> i see
[11:53:22] <OndraSter> I can make them always in the middle
[11:53:34] <amee2k> hmm i was thinking ground plane on bot, traces from the MCU to xtal and caps on top
[11:53:44] <amee2k> and vias at the caps that go straight down into the ground plane
[11:54:17] <amee2k> there was an appnote on that... rf travels the path of least impedance, which isn't neccessarily the path of least resistance anymore
[11:54:39] <amee2k> so trace over a ground plane means the majority of the rf current will return right under the trace
[11:55:59] <amee2k> least impedance == least loop area :)
[11:58:00] <OndraSter> like this?
[11:58:00] <OndraSter> http://clip2net.com/s/1w9IB
[11:58:45] <amee2k> yeah, that looks pretty nice i'd say
[11:59:17] <OndraSter> and MCU's GND pin to that directly or trace it to USB's GND pin and make separate paths?
[11:59:41] <OndraSter> and other GND paths separate
[12:05:41] <OndraSter> I am hungry from all this wiring
[12:05:49] <OndraSter> and it is driving me mad, really
[12:11:35] <amee2k> hehe
[12:11:45] <amee2k> hmm whats the xtal have to do with USB ground?
[12:12:42] <OndraSter> where should I connect the grounds
[12:13:05] <OndraSter> USB is used to power this board
[12:14:18] <OndraSter> ZOMG EU leaders do not know why our govt wants referendum if we want to join fiscal union LOL
[12:16:14] <amee2k> i'd run the xtal ground to the closes ground pin on the MCU. then from there to the rest of the digital ground
[12:17:19] <OndraSter> ok
[12:19:12] <amee2k> i'm not entirely sure how usb ground and normal mcu/digital ground are supposed to be different
[12:19:52] <Kevin`> amee2k: my reading was that they are the same potential. the difference is just where the current will be flowing
[12:20:13] <amee2k> hmm i see
[12:21:29] <OndraSter> ye
[12:21:32] <OndraSter> where they will all meet
[12:27:56] <OndraSter> how about decoupling 100nF caps being soldered from the other side of the board?
[12:28:02] <OndraSter> with vias
[12:30:09] <OndraSter> hmm AREF... no cap there
[12:30:19] <OndraSter> in sample layout
[12:32:50] <amee2k> lots of people use bypass caps on the bottom, especially for large parts where putting them on top around the IC would interfere with other stuff
[12:32:56] <OndraSter> okay
[12:33:00] <OndraSter> and no AREF cap
[12:33:04] <OndraSter> just AVCC
[12:33:15] <amee2k> but double sided automated assembly is more expensive for production
[12:33:33] <OndraSter> I am glad I don't use automated assembly machine then :P
[12:34:40] <asteve> in a board as small as a pcb doesn't bypass cap placement greatly affect the desired filtering?
[12:40:13] <atmega> you can glue the bottom components, this is not suche a big problem
[12:40:40] <OndraSter> glue xD reminds me of being young when I had to try tasting a glue
[12:40:42] <OndraSter> as we all did
[12:41:28] <theBear> that doesn't sound like something i'd do.... i like to smell things, but not taste them, at least not at that age
[12:43:41] <amee2k> better than sticking it in the pooper
[12:43:43] * amee2k runs
[12:45:04] <theBear> yeah, that's a bad place i would imagine for glue to be a stickin
[12:45:05] * RikusW just fixed a borehole pump
[12:46:47] <amee2k> RikusW: http://ompldr.org/vY2Zmcw/2012-01-24-154744.jpg
[12:47:55] <RikusW> ah the ic that got bitten ;)
[12:48:00] <amee2k> yep
[12:48:21] <amee2k> found it in the junk box... the /junk/ junk box, that is. no idea what it does
[12:48:40] <RikusW> datasheetarchive ?
[12:49:35] <amee2k> wasn't very conclusive but i didn't look too closely
[12:49:59] <amee2k> can't even tell the manufacturer from the logo
[12:51:59] <RikusW> it might be an eeprom
[12:52:06] <RikusW> http://www.datasheetarchive.com/
[12:52:14] <RikusW> search for t65c
[12:52:43] <amee2k> CS4336 is an audio codec apparently
[12:53:02] <RikusW> in 8 pins
[12:53:04] <RikusW> ?
[12:53:18] <amee2k> "8-Pin, 24-Bit, 96 kHz Stereo D/A Converter"
[12:53:23] <amee2k> from cirrus
[12:54:00] <RikusW> turns out a franklin starter box costs ZAR900 == 90 E for a 95uF 250Vac cap + relay + overload trip....
[12:54:08] <amee2k> a ton of ST MCUs comes up too
[12:54:57] <RikusW> luckily the motor itself was intact
[12:55:04] <RikusW> lightning....
[12:57:02] <amee2k> eeew
[12:57:42] <RikusW> seems expensive ?
[12:58:21] <amee2k> lightning?
[12:58:28] <amee2k> haven't ordered any before >_>
[13:00:03] <RikusW> yeah split the top of the power company's poles at the top...
[13:01:29] <amee2k> 0.0
[13:16:35] <Bushman> lightnings are fun...
[13:16:50] <RikusW> and expensive...
[13:16:51] <Bushman> especially on top of power poles
[13:17:03] <Bushman> yea, i know. rite?
[13:17:15] <Bushman> i wanted to make 1kw tesla
[13:17:24] <RikusW> fortunately my PC was unplugged at the time
[13:17:31] <Bushman> pretty much expensive
[13:19:58] <RikusW> and jam _all_ local radio stations ? ;)
[13:24:27] <amee2k> http://amee2k.deviantart.com/gallery/#/d2u1iid
[13:28:01] <Casper> amee2k: that's why I want a pricier camera next time
[13:28:08] <Casper> so I have less grain in my pics
[13:28:15] <Casper> the issue is the tiny sensor in the camera
[13:28:28] <amee2k> Casper: on second thought the grainy quality looks pretty cool imo
[13:28:29] <Casper> tiny = not much light shining on it...
[13:28:40] <Casper> it's not that bad in your
[13:28:49] <amee2k> what was somewhat frustrating though was the trigger
[13:28:52] <Casper> the long exposure help
[13:29:02] <amee2k> 1 second was the longest setting
[13:29:14] <amee2k> i want one with external trigger so i can connect a photodiode circuit
[13:29:23] <amee2k> or an EMI based trigger on the strike
[13:29:43] <Casper> do you happend to have a canon?
[13:29:51] <amee2k> no, casio exlim
[13:29:55] <Casper> :(
[13:30:12] <amee2k> i like it a lot
[13:30:17] <amee2k> makes pretty cool pics
[13:30:34] <Casper> on canon you have CHDK
[13:30:42] <amee2k> "CHDK"?
[13:31:13] <Casper> http://chdk.wikia.com/wiki/CHDK
[13:32:28] <asteve> veryone ever should buy this https://www.livingsocial.com/deals/186766?ref=conf-jp&rpi=44809006
[13:32:32] <amee2k> all i want is a 2.5mm jack or something that exposes the trigger signal
[13:33:22] * amee2k . o O ( if the seeed logo had one more leaf it would almost look like a ganja leaf... )
[13:33:45] <Casper> amee2k: with the CHDK you don't even need that, there is a great scripting interface, that can trigger on visual events, fast enought to catch lighting
[13:34:06] <amee2k> okay
[13:35:41] <outerspase> I helped design a device that triggers a camera when lightning strikes check it out here http://www.ubertronix.com/products-page/product-category/strike-finder/
[13:37:31] <outerspase> theres connectors for the trigger on most cameras, you can select the one you need when you buy a strikefinder
[13:38:28] <outerspase> you have about 200ms to capture lightning so its even possible to use your own reflexes if you have them
[13:39:01] <asteve> lightning doesn't move at the speed of light?
[13:40:53] <outerspase> it does but its continuous for 200+ ms
[13:41:00] <amee2k> doesn't list casio
[13:41:26] <outerspase> send the guy an email he knows a lot about camera triggers
[13:42:05] <outerspase> hey dean
[13:42:06] <amee2k> do they have any information on that product page, besides that the product exists?
[13:43:29] <outerspase> theres some more stuff here, http://www.electronics-hobby.com/products-page/gadgets/strikefinder/
[13:43:37] <outerspase> excuse his web design skills
[13:44:21] <outerspase> what are you up to lately abc?
[13:44:34] <abcminiuser> Heyo
[13:44:39] <abcminiuser> Working on AVR support
[13:44:45] <outerspase> im outer_space from avrfreaks
[13:44:48] <abcminiuser> You know, the usual avr at atmel dot com
[13:45:18] <outerspase> you work at atmel?
[13:46:09] <amee2k> except for it has a led and a 9V battery thats the same text as on the other page
[13:46:11] <abcminiuser> Yup, as of the 9th
[13:46:14] <abcminiuser> Moved to Norway
[13:46:49] <LoRez> and you're doing AVR support?
[13:47:27] <outerspase> I havnt gone to avrfreaks in forever but have been getting some circuit design work lately, and teaching an arduino class at geekdom.com
[13:47:45] <OndraSter> abcminiuser, quick Q for atmel support then: why didn't I receive any response to my samples request on atmel? :(
[13:47:45] <abcminiuser> Yeah, for a few weeks until I go on ASF development
[13:48:05] <abcminiuser> OndraSter, if you submitted it to the general support, we don't do it
[13:48:11] <abcminiuser> Contract your distributor
[13:48:15] <outerspase> they forward your request to your regional sales reps who are supposed to contact you
[13:48:20] <abcminiuser> Any samples Atmel Norway has are for our own use :P
[13:48:29] <OndraSter> abcminiuser, I submitted it on atmel's website :P
[13:48:38] <OndraSter> there was form for it
[13:48:41] <abcminiuser> Well in that case no idea, doesn't go through us
[13:48:41] <Casper> atmel do not sample
[13:48:44] <OndraSter> ah
[13:48:48] <abcminiuser> Probably auto-forwarded to the distri
[13:48:50] <OndraSter> Casper, huh, I remember filling that form
[13:48:50] <outerspase> it normally takes months
[13:49:08] <amee2k> http://ompldr.org/vOXlwcA/CIMG8428b.JPG http://ompldr.org/vOXlwbw/CIMG8425b.JPG << two lucky shots i made from the kitchen window last fall
[13:49:10] <abcminiuser> I'd probably recommend you just fork out the few bucks, it's quicker :P
[13:49:21] <Casper> there is a sample form, but I never hear of anyone that got a sample from atmel
[13:49:38] <Casper> some distributor however does sample if they think you are going to buy alot from them after
[13:49:40] <Casper> bbl
[13:49:43] <abcminiuser> Casper, never tried it, but that probably goes through the US group
[13:50:16] <abcminiuser> Also I will hurt you if you submit a support request with just "it doesn't work"
[13:50:29] <outerspase> now that you can buy an arduino at radioshack it should be easy to get an AVR if you really need one
[13:51:15] <abcminiuser> Had a request from a guy that wasn't sure if his hardware was correc
[13:51:17] <abcminiuser> *correct
[13:51:27] <abcminiuser> I wrote a quick test app, tested it, sent him the code
[13:51:35] <RikusW> atmel does give sample
[13:51:38] <abcminiuser> He came back saying he doesn't like C and so he re-wrote it in ASM
[13:51:57] <abcminiuser> Doesn't work, I try it and find it's buggy, so I fix it and send it back
[13:52:00] * RikusW got it through the local Atmel distributor
[13:52:12] <abcminiuser> He comes back with a second, new ASM version that doesn't work either
[13:52:18] <OndraSter> lol
[13:52:20] <OndraSter> normal stuff
[13:52:22] <abcminiuser> So I ended up just sending back a HEX file :S
[13:52:32] <RikusW> and it did take a _long_ time
[13:52:44] <abcminiuser> If you think something's HW related, why not run the known working code regardless of what it's written in? :S
[13:53:32] * RikusW got it from arrow-altech
[13:56:06] <RikusW> HEX file, LOL
[13:57:41] <RikusW> abcminiuser: exactly
[14:01:23] <OndraSter> http://clip2net.com/s/1wbys
[14:01:50] <OndraSter> quite empty board I'd say
[14:01:55] <OndraSter> but space is not an issue
[14:02:00] <OndraSter> I am doing 3 layered sandwich now lol
[14:03:24] <amee2k> 0.0
[14:03:55] <OndraSter> I mean
[14:03:59] <OndraSter> 3 PCBs above itself
[14:04:02] <OndraSter> not 3 layers
[14:04:08] <amee2k> is taht going to be the topmost board?
[14:04:56] <OndraSter> no
[14:04:59] <OndraSter> bottom layer
[14:05:06] <OndraSter> bottom = powerboard + logic board
[14:05:09] <OndraSter> middle = driver boards
[14:05:18] <OndraSter> top = LEDs
[14:05:31] <amee2k> so the jtag header is sticking out of the bottom?
[14:05:50] <OndraSter> uh?
[14:05:52] <OndraSter> oh
[14:05:57] <OndraSter> I can always change the layout :)
[14:06:02] <OndraSter> it will be programmed once through JTAG
[14:06:03] <OndraSter> and debugged
[14:06:06] <OndraSter> and then flashed from USB
[14:06:08] <amee2k> or how are you going to reach it if it is the bottom board >_>
[14:06:22] <OndraSter> if it wasn't so much wires, I'd put it to the back side
[14:06:59] <amee2k> mmh, dinner first. then i can commence thinking lol
[14:07:02] <abcminiuser> Did we ever get a reason why Tom_itx fell off his twig?
[14:07:19] <amee2k> not that i remember
[14:07:40] <OndraSter> twig?
[14:08:11] <abcminiuser> OndraSter, monty python
[14:08:14] <OndraSter> ah
[14:08:16] <abcminiuser> (I mean he's dead, not around)
[14:08:24] <abcminiuser> Also, LOOK AT THIS SEXY TYPESETTING: https://deans-avr-tutorials.googlecode.com/svn/trunk/Timers/Output/Timers.pdf
[14:08:26] <amee2k> twig (plural twigs)
[14:08:27] <amee2k> A small thin branch of a tree or bush.
[14:08:36] <OndraSter> I know what is twig
[14:08:39] <OndraSter> that doesn't explain it though :P
[14:08:52] <amee2k> not really
[14:09:04] <amee2k> i mean, why would he climb on a bush >_>
[14:10:09] <abcminiuser> amee2k, *snigger*
[14:10:35] <amee2k> was that tyo'd for *nigger* ?
[14:10:36] * amee2k runs
[14:15:54] <abcminiuser> ?
[14:15:58] <abcminiuser> No.
[14:17:32] <Steffanx> Yes
[14:17:46] <amee2k> twss
[14:22:15] <LoRez> don't be a d-bag
[16:19:58] <CapnKernel> !last Tom_itx
[16:20:21] * amee2k reappears
[16:20:50] <amee2k> OndraSter: how about moving the jtag header to the edge of the board so you can put a 90° header on?
[16:21:42] <amee2k> OndraSter: also, how are you holding the board stack together? stand-offs?
[16:22:35] <Steffanx> !seen bla
[16:22:47] <Steffanx> !thislog
[16:22:49] <Steffanx> !logthis
[16:22:53] <Steffanx> CANUCK
[16:23:00] <amee2k> canuklog
[16:23:01] <Steffanx> Oh, tobbor isn't here
[16:23:10] <amee2k> probably taking a shower
[16:23:17] <Steffanx> !seen tobbor
[16:41:03] <keenerd> Wonder if you could fit a programming header into 2mm with these http://solarbotics.com/products/pp8-40/
[16:41:19] <OndraSter> amee2k, it is already on the edge... just not sure if rotated on the proper side, gotta replace it with 90° header in the schematics :P
[16:41:20] <OndraSter> ye
[16:41:21] <OndraSter> standoffs
[16:41:25] <OndraSter> gotta calc the target values
[16:41:46] <amee2k> i see
[16:41:56] <amee2k> wasn't sure since i didn't notice any mounting holes
[16:42:30] <OndraSter> yeah
[16:42:43] <OndraSter> I will probably make it on the edges and make the math there
[16:42:53] <OndraSter> I am still not sure how it is gonna be laid out in the end
[16:42:58] <OndraSter> there are so many possibilities!
[16:43:03] <OndraSter> I might even make two PSUs also :P
[16:43:14] <OndraSter> because I will be now writing two lines at once
[16:43:19] <OndraSter> so two 5A :P
[16:43:36] <amee2k> heh
[16:43:48] <OndraSter> again, plenty of space... la la la :)
[16:43:52] <OndraSter> extra boards will be anyway
[16:43:58] <OndraSter> 4 TPS54527 available too
[16:44:07] <OndraSter> they are expensive :o)
[16:44:14] <OndraSter> TI rox lol
[16:45:21] <amee2k> maybe find an SMP controller that is just the controller + gate driver
[16:45:32] <amee2k> and uses an external transistor
[16:46:05] <OndraSter> I am fine with what I have now
[16:46:12] <OndraSter> with a bit of luck I could probably fit them both on one board
[16:47:43] <amee2k> an external D-PAK MOSFET can handle a lot more power than a flimsy SOT
[16:47:54] <OndraSter> well yeah
[16:47:59] <OndraSter> but I have plenty of these already :P
[16:48:13] <amee2k> hehe
[16:48:18] <amee2k> what when they run out?
[16:48:55] <OndraSter> I need 4, got 5
[16:49:05] <amee2k> okay
[21:15:08] <learningc> any fast an easy way to convert a mono bmp file into 2-d C array?
[21:16:34] <Landon> I think gimp does that
[21:16:59] <Landon> (the image editor)
[21:17:37] <learningc> ak ok, I'm gonna take a look at it, thanks
[21:17:53] <Landon> yup, just select C source or C header when you "Save as"
[21:19:23] <learningc> cool! thanks
[21:19:44] <BrentBXR_> any of you guys ever deal with scanf in embedded projects?
[21:20:00] <BrentBXR_> any pro/cons besides the usual size blah blah
[21:20:12] <BrentBXR_> i mean function wise
[21:21:32] <BrentBXR_> I need to design a really nice terminal interface even if it means upping the caps on the current 64 mega
[21:22:19] <Kevin`> BrentBXR_: I have. it works of course. I probably used sscanf to be not blocking though
[21:22:59] <BrentBXR_> true I would imagin sscanf would need to be used
[21:23:23] <BrentBXR_> atleast with my current setup of getting one char at a time; i will have to buffer and length the text myself before being passed to scanf
[21:23:57] <BrentBXR_> and ensure all vs1000 works (del, escape, ...) and sends the correct string to scanf
[21:26:34] <BrentBXR_> i just want a interface that can process real commands, like be able to send 0x45 0x45 123
[21:27:01] <BrentBXR_> in any order and it knows i want hex 45 45 and dec 123
[21:27:04] <BrentBXR_> stuff like that
[21:27:04] <Kevin`> BrentBXR_: the avr-libc example stdio stuff has some terminal handling. works pretty nice actually, although it's designed to work with the blocking interface
[21:27:17] <Kevin`> not that that should stop you from using it as an example
[21:27:47] <BrentBXR_> I know; I have done it before but usually revert back to like
[21:28:10] <BrentBXR_> send 's' -> it knows the next two numbers are hex and the next number is the repeat for example
[21:28:31] <BrentBXR_> it would perfer it doesnt matter the order and so on; i think if I perhaps
[21:28:38] <Kevin`> somewhere around I have a project that will automatically translate 0xYYY and 0bYYY appropriately. I wish I could find it to avoid having to rewrite it, it was nice
[21:29:09] <BrentBXR_> say the string "s 0x45 r10" and send scanf: "s" "0x45" "r10" and it knows ok one line so one command, send 0x45 ten 10's
[21:29:28] <BrentBXR_> yes
[21:29:42] <BrentBXR_> that is what im saying :D
[21:31:06] <BrentBXR_> I came in late in a project with a great comm interface designed for a pic project
[21:31:08] <Kevin`> and that combined with line editing, of course
[21:31:20] <BrentBXR_> i would love to port all of that into a working AVR library to share
[21:31:37] <BrentBXR_> it does your type stuff
[21:32:15] <BrentBXR_> 0x means hex. 0b means bin, YY:## means repeat YY ## times, stuff like that
[21:32:34] <BrentBXR_> and order does not matter but it would be a huge pain
[21:32:47] <Kevin`> oh, come to think of it, bus pirate probably has code for all of that stuff
[21:32:56] <BrentBXR_> thats the project
[21:33:02] <BrentBXR_> it would be a pain tho because
[21:33:13] <BrentBXR_> it wasnt designed to shar ehte interface so if you look into the code
[21:33:22] <BrentBXR_> alot of stuff is all over the place
[21:33:37] <BrentBXR_> ':' handing for example is in every mode
[21:33:42] <BrentBXR_> even though its universal
[21:33:55] <BrentBXR_> but thats because for example HiZ does not accept :
[21:34:33] <learningc> ok, how is that c header array organised when converting a bmp into it?
[21:35:02] <BrentBXR_> Although Ian had great intentions of making it open domain so anyone can use any of hte source as they please, its such a long project
[21:35:14] <BrentBXR_> stuff added to stuff makes it very hard to pick out just what you want
[21:36:06] <BrentBXR_> learningc, is it for being shown on a LCD or somthing
[21:37:05] <learningc> yeah, something like that
[21:37:24] <learningc> BrentBXR_: more like a led matrix
[21:37:39] <BrentBXR_> i came accross a site dedicated to LCD projects it has some great BMP to C converters + examples and stuff
[21:37:43] <BrentBXR_> let me see if I can find it
[21:37:52] <learningc> ok
[21:38:30] <learningc> I need something that give direct correspondence of bmp into a matrix
[21:39:04] <learningc> but the matrix is a 2d c array
[21:39:42] <Kevin`> gimp apparently has a c array output option
[21:39:43] <BrentBXR_> heres a break down of BMP to C
[21:39:48] <BrentBXR_> http://www.geocities.com/dinceraydin/lcd/gfxhowto.htm
[21:39:53] <BrentBXR_> i didnt read it just found it right now
[21:39:56] <BrentBXR_> but looks interesting
[21:40:00] <BrentBXR_> ill keep looking for that one site
[21:40:13] <learningc> ok, thanks
[21:40:16] <BrentBXR_> also see
[21:40:16] <BrentBXR_> http://www.geocities.com/dinceraydin/lcd/index.html
[21:40:30] <BrentBXR_> how big is your matrix?
[21:40:34] <BrentBXR_> what x what
[21:41:07] <timemage> dunno if it helps, but gimp will save images as C files along with a macro to access the pixels.
[21:41:48] <keenerd> *reocities
[21:42:20] <BrentBXR_> lol i know who uses geo cities anymore
[21:42:32] <keenerd> Wait, Geocities is back now?
[21:42:54] <vectory_> last time i tried gimp export to *.h it wasnt working :(
[21:43:14] <keenerd> People moved a small continent backing up Geocities when they said they'd get rid of it.
[21:43:50] <learningc> yeah, but how gimp saves the bitmap?
[21:44:13] <timemage> learningc, very carefully?
[21:44:19] <learningc> for example:
[21:44:22] <learningc> 1 0 0 1
[21:44:28] <learningc> 1 1 0 1
[21:44:38] <learningc> let's say this it the bmp image
[21:45:08] <learningc> how will it appear in c header created by gimp?
[21:45:26] <timemage> learningc, somewhat ugly. it's packing into into a string.
[21:45:27] <vectory_> cant say, without looking at the created header ;(
[21:45:30] <keenerd> Just try it yourself :-)
[21:45:39] <BrentBXR_> I would imagin 0x## corisponding to color of pixel
[21:45:51] <BrentBXR_> but iv never tried it myself
[21:45:54] <learningc> keenerd: it seems longer than my bmp image
[21:46:10] <BrentBXR_> if thats the case then you could simply convert anything not black to 1 and black to 0 in your own code
[21:46:12] <keenerd> Well yeah, it is ascii.
[21:46:21] <learningc> BrentBXR_: I'm doint mono though
[21:46:21] <BrentBXR_> or somthing
[21:46:41] <BrentBXR_> im not into BMP lingo
[21:46:55] <BrentBXR_> what does that mean? just black and white?
[21:47:08] <vectory_> i imagine bmp is not much different to ppm
[21:48:00] <vectory_> i wrote a ppm to *.h converter in sed, and a ppm reader in c. at least one of the components fails tho and i didnt find the time to debug it >_<
[21:48:58] <keenerd> Ugh. Why does no one make an instrumentation op amp that lets you use a gain <1? Everyone's are >5.
[21:49:21] <BrentBXR_> im not a big LED or toy type guy; leds are just indicators to me (in my projects) so I dont have any experince in it; but i got think its really not much different then BMP to LCD
[21:49:27] <BrentBXR_> well not color lcd
[21:49:42] <learningc> ah, I figured out
[21:49:53] <learningc> it saves it the same way
[21:50:03] <timemage> learningc, http://ideone.com/VEl24 that's a two by two pixel image, black on white, black diagnal.
[21:51:07] <timemage> spelled incorrectly in both places for consistency. =)
[21:51:16] <keenerd> Guess I'll have to do something dumb like feed the instr op amp into a voltage divider just to get the signal into the AVRs range.
[21:54:02] <BrentBXR_> keenerd, cannot use inverting mode with feedback resistor less than the input resistor
[21:54:41] <BrentBXR_> that was a question
[21:55:39] <keenerd> These are intrumentation amps. They come with pre-trimmed resistors.
[21:55:40] <BrentBXR_> i thought sound related they used opamps at <1 quite a bit; using unity invert
[21:56:13] <keenerd> These are *not* op amps.
[21:56:18] <BrentBXR_> oh
[21:56:19] <keenerd> BrentBXR_: See http://www.ti.com/lit/ds/symlink/ina126.pdf
[21:56:23] <BrentBXR_> mah bad
[21:56:43] <keenerd> They are made of op amps, so close enough :-)
[21:56:58] <BrentBXR_> interstinky
[21:57:59] <BrentBXR_> lol under there gain section your stuck
[21:58:10] <BrentBXR_> even there equation is g = 5 + <formula>
[22:00:05] <BrentBXR_> what are these for?
[22:00:20] <BrentBXR_> iv never done music either; again entertainment not my type projects
[22:01:27] <keenerd> Pretty much any time you want to use an op amp to measure something as acurately as possible, you use one of these.
[22:02:30] <keenerd> The main advantage is input impedance around a billion ohms.
[22:02:42] <BrentBXR_> http://www.analog.com/static/imported-files/Data_Sheets/AD8553.pdf
[22:03:29] <Roklobsta> kkenerd: you're a champ. i am looking for something like that
[22:04:12] <Roklobsta> autozero is good. gets rid of the 1/f noise problme.
[22:04:32] <BrentBXR_> looks like it can handle a gain 1
[22:04:45] <BrentBXR_> autozone and 1-5v operating
[22:04:59] <Roklobsta> i don't like the 1-5V .
[22:05:01] <keenerd> Indeed, thank you for finding that chip series. Now I just need a 12V version.
[22:05:36] <Roklobsta> have a look at ti an national and some others, they have autozeroing opamps too
[22:05:46] <Roklobsta> love a good chpper.
[22:05:48] <Roklobsta> chopper
[22:06:24] * Roklobsta realises maybe 2 others know what a chopper in this context is.
[22:08:04] <BrentBXR_> keenerd, http://cds.linear.com/docs/Datasheet/1789fc.pdf
[22:08:14] <BrentBXR_> LT1789-10 specificly
[22:08:22] <BrentBXR_> ~30v max
[22:08:58] <keenerd> Thanks! (I was still digging though ADs line.)
[22:09:17] <BrentBXR_> or LT1789-1
[22:09:18] <BrentBXR_> not 10
[22:11:48] <BrentBXR_> I got one of those touchstone T1001 opamp demo sample boards
[22:12:05] <BrentBXR_> now there president of marketing wont stop calling me
[22:12:31] <BrentBXR_> i used my work email address when i ordered it so i think he thinks its for my work not myself personally
[22:12:34] <BrentBXR_> what a sucker
[22:12:36] <BrentBXR_> :D
[22:13:08] <BrentBXR_> never used it; wtf do i do with an opamp demo board
[22:15:46] <BrentBXR_> any of you guys get one of those MSP430 development boards from TI?
[22:16:06] <BrentBXR_> man I got two of those :D figure somthing out with it; couldnt pass it down
[22:16:20] <vectory_> have the launchpad for 15€
[22:16:35] <BrentBXR_> whats that translate too in $
[22:16:36] <vectory_> never used once since i got it a 2 month ago
[22:16:56] <vectory_> BrentBXR_: rougly the same: overpriced ;)
[22:16:57] <BrentBXR_> yeah iv had mine for a while too; never even downloaded the IDE
[22:17:01] <keenerd> They've got really good ADC and DAC on them. Make a chiptune bender thingy.
[22:17:09] <BrentBXR_> i paid 4 bucks
[22:17:12] <BrentBXR_> that included shipping
[22:17:34] <BrentBXR_> actually included alot ofr 4 bucks
[22:17:44] <BrentBXR_> hell the USB cable it came with is ~4$
[22:18:11] <BrentBXR_> next time i need a USB cable im just going to buy one of those
[22:18:27] <BrentBXR_> i wonder if the attiny2313 works on it; as in pin compatible
[22:18:47] <vectory_> nope
[22:18:51] <BrentBXR_> poop
[22:18:56] <vectory_> different acc gnd pins afaik
[22:19:28] <BrentBXR_> yep
[22:19:58] <vectory_> or maybe not, was thinking of mega8
[22:20:08] <vectory_> anyway, thje supply voltage might differ
[22:20:16] <BrentBXR_> no it doesnt there GND and VCC are the top* two pins
[22:20:37] <vectory_> k :(
[22:20:43] <BrentBXR_> as in 1 and what ever is accross from that
[22:21:02] <vectory_> PINMAX/2+1 :D
[22:21:08] <BrentBXR_> :D
[22:21:25] <BrentBXR_> the little micro crystal that came with it is pretty sweet
[22:21:33] <vectory_> or just PPINMAX, in most cases
[22:22:11] <vectory_> no doubt its a good package, but the mcs arent the best of the line
[22:22:44] <BrentBXR_> i think there only selling point is the very low power consumption
[22:22:58] <BrentBXR_> like on youtube there are MCP's running off of lemons and stuff
[22:23:29] <BrentBXR_> but 99% of the stuff i do is USB powered so I never had to deal with power consumption issues in detail
[22:24:30] <BrentBXR_> well i think my dog is telling me its time for bed; night guys.
[22:24:39] <BrentBXR_> well 15 more minutes
[22:24:42] <vectory_> n8
[22:24:52] <vectory_> haha
[22:25:05] <BrentBXR_> any cool projects lately?
[22:25:18] <BrentBXR_> I have not touched code in weeks
[22:25:27] <BrentBXR_> have done a bit of soldering but i have no ideas atm
[22:25:48] <vectory_> no, im stalling
[22:25:57] <BrentBXR_> im thinking about converting a cheap USBASP to be a PDI programmer for the xmega family
[22:26:01] <BrentBXR_> i think that would be sweet
[22:26:25] <BrentBXR_> PDI from what i understand is just U(S)ART with TX and RX tied
[22:26:53] <BrentBXR_> prolly hook up my debugger to a bus pirate and see what its transmitting
[22:26:55] <vectory_> no idea
[22:27:19] <vectory_> just search doku?
[22:27:24] <vectory_> docs*
[22:27:26] <BrentBXR_> that would be sweet tho; a 5$ open source and diy xmega programmer
[22:27:39] <BrentBXR_> yes; they do explain the pdi interface abit
[22:27:54] <BrentBXR_> but i think they are trying to keep the actual communication a secret
[22:28:00] <BrentBXR_> like there debugwire
[22:28:17] <BrentBXR_> which is the same as pdi as u understand just UART not USART
[22:29:47] <BrentBXR_> alright well im off