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[00:00:03] <inflex> for post-regulation?
[00:00:12] <inflex> so, get a car laptop PSU?
[00:00:52] <Casper> thing is
[00:01:05] <Casper> I found one thing that would do it, but I'm worried about the reliability
[00:01:23] <Casper> http://www.mini-box.com/OpenUPS?sc=8&category=981 ← that
[00:01:26] <inflex> ja, that's what I'm worried about too - especially if you end up with two chained switch-mode units (ie, default mode)
[00:01:49] <inflex> Exotic.
[00:02:21] <Casper> but the only "black box" I could find
[00:02:38] <Casper> feed 19VDC, plug batt, have 12V out
[00:02:39] <inflex> http://www.mini-box.com/picoUPS-100-12V-DC-micro-UPS-system-battery-backup-system?sc=8&category=981
[00:02:53] <Casper> that's a diode OR with mosfet
[00:03:19] <inflex> they work well :\
[00:03:44] <Casper> yes, if you have 13.65V regulated already
[00:04:51] <Casper> sorry, 15-18V in, and have a linear battery charger... but still no regulation out
[00:06:02] <Casper> ow well, I'll continue to look...
[00:07:46] <Casper> LOL yeah... that diode or thing...
[00:07:51] <Casper> it have a lm317 onboard :D
[02:02:30] <Eartaker> the ATMEGA328P has an internal oscillator so why do people use an external?
[02:03:28] <dioxide> higher speed, more precise
[02:04:23] <dioxide> im not sure about that particular model, but the chips ive seen with internal oscillators never run at the max speed of the chip
[02:04:50] <dioxide> ah yeah
[02:04:52] <dioxide> its only 8mhz
[02:04:55] <Eartaker> I would only need it for a debounce for a few momentary switches, think I could get away with the internal or should I just add the external?
[02:05:09] <Eartaker> hmm
[02:05:09] <dioxide> an external can go to 20
[02:05:36] <Eartaker> ill add it i guess
[02:05:48] <Xark> Eartaker: Internal is more than adequate for that use I would think (you could run with div8 for 1Mhz and be fine).
[02:06:03] <dioxide> just for debounce? certainly. how many switches? id probably just use a $.75 attiny instead, unless you already have it
[02:06:23] <Eartaker> ill have 4 switches and 1 button
[02:07:04] <Eartaker> what will happen is 2 switches will be tripped at start, button is presses and the program runs a few pumps until the other 2 are tripped
[02:07:15] <dioxide> youre wasting a fairly robust chip on that
[02:07:30] <Eartaker> easy just never done this with just ann AVR
[02:07:48] <Eartaker> dioxide: yes I know... but i suck at C and was going to put the arduino bootloader on it
[02:07:57] <dioxide> i see
[02:08:00] <dioxide> fair enough
[02:08:02] <Eartaker> or I guess I could brush up on my C and get a smaller chip
[02:08:37] <Xark> Eartaker: The Arduino can be extended for ATTiny etc. (but you will need an ISP programmer).
[02:08:45] <Xark> Er, Arduino IDE
[02:08:51] <Eartaker> who knoaws though it would also give me room to add on
[02:09:21] <Eartaker> Xark: I dont want to use the arduino programmer, I was hoping to just use a serial programmer
[02:09:22] <Xark> Eartaker: Sure. 328 is overkill, but still pretty cheap. :)
[02:09:46] <Eartaker> Xark: $3 on digikey
[02:10:00] <Xark> Eartaker: OK, but hopefully your chip is already programmed with the Arduino bootloader (or else chicken-and-the-egg).
[02:10:35] <dioxide> put an isp header on your target board and get a serial programmer
[02:10:36] <Eartaker> Xark: its not... the pre programmed one is $9... I was hoping to load it myself so yes I guess I will need a programmer
[02:10:49] <dioxide> theyre pretty cheap
[02:11:13] <Eartaker> have a link to a good cheap one? Im new to the AVR as you can see =/
[02:11:30] <dioxide> sparkfun sells one, sec ill seek it out
[02:11:37] <Eartaker> I think I found it
[02:12:00] <Eartaker> https://www.sparkfun.com/products/9825
[02:12:01] <Eartaker> ?
[02:12:03] <dioxide> https://www.sparkfun.com/products/9825
[02:12:09] <Xark> Also
http://www.adafruit.com/products/46
[02:12:34] <dioxide> https://www.sparkfun.com/products/11460 as well
[02:12:57] <dioxide> the usbtinyisp is the ideal one tho, the one xark linked
[02:13:01] <dioxide> thats the one i was looking for
[02:13:10] <Eartaker> hmm
[02:13:27] <Xark> Yeah, I have that one and it works well (and is directly supported right from Arduino IDE).
[02:14:01] <Eartaker> nice and from reading I can use it with almost all AVR's
[02:14:08] <dioxide> its versatile
[02:14:10] <Xark> Yep.
[02:14:33] <Xark> It can even provide 5v power during development (if needed - jumper selectable).
[02:14:49] <dioxide> yeah keep that in mind when programming 3.3v chips
[02:15:08] <Eartaker> I should build a dev board while im at it
[02:15:20] <Xark> It will program 3.3v chips no problem, just don't use its power supply. :)
[02:15:31] <dioxide> exactly
[02:16:15] <Eartaker> oh damn, adafruit has the AVR preloaded with the bootloader for $6
[02:16:33] <Eartaker> how hard is it to load the bootloader though?
[02:16:40] <Xark> Eartaker: Sooner or later you will really want an ISP...
[02:16:42] <dioxide> if you have the isp, its simple
[02:16:49] <dioxide> just grab the isp and save yourself grief
[02:17:02] <Eartaker> Xark: I was planning on getting the ISP
[02:17:05] <Xark> Eartaker: Just select "burn bootloader" in Arduino IDE (after selecting USBTiny as programmer).
[02:17:43] <Xark> Eartaker: It will set the fuses correctly for Arduino and burn the bootloader.
[02:18:05] <dioxide> spending extra for preprogrammed chips is such a waste
[02:18:19] <Xark> Eartaker: Note that for "standard Arduino" you will need external 16Mhz crystal. However, there are supported derivatives at 8Mhz that can use internal RC osc.
[02:18:36] <Eartaker> hmm from what I know I have to have the bootloader on the chip to use the arduino compiler but whats the point of the bootloader?
[02:18:52] <Xark> (but make sure to burn the 8Mhz "board" before burning bootloader or it won't work)
[02:19:16] <Xark> Eartaker: Well, if you have ISP, not much. :)
[02:19:17] <dioxide> the bootloader lets you drop new roms onto the chip over usb, without a programmer
[02:19:41] <Eartaker> oh, so if I have the ISP I dont need to load the bootloadeR?
[02:19:47] <dioxide> right
[02:19:55] <Eartaker> awesome that works great
[02:20:09] <dioxide> well maybe you do, i dont use arduino stuff myself, prefer the direct route
[02:20:21] <Xark> Eartaker: You just use "shift-upload" to upload sketch from IDE using ISP. Also small AVR chips like ATTiny45/85 don't have a serial port (so you need ISP even with Arduino IDE).
[02:20:21] <dioxide> but either way, the isp is invaluable
[02:20:32] <Eartaker> well im looking to make a few of the chips the same so easy is best
[02:21:13] <Eartaker> im sold on the ISP... i guess Ill order it and a few chips to play with
[02:22:35] <Eartaker> was hoping to order from a single site... damn
[02:23:50] <Xark> Eartaker: Hehe. Well, if you really want you can order "official" programmer from Digikey along with blank AVR chips ->
http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891 (however, you will need to use bloated AVR studio to burn your sketches AFAIK).
[02:24:20] <dioxide> sparkfun sells avrs too, dunno if the price is competitive tho
[02:24:41] <Eartaker> hmm
[02:24:55] <Xark> Either way, you will get them pre-loaded with bootloader I bet. :) (and probably comparable price).
[02:25:32] <Eartaker> dow, same programmer 2x the price
[02:25:38] <Eartaker> https://www.sparkfun.com/products/8702
[02:25:43] <Eartaker> adafruit it is
[02:26:03] <dioxide> thought sparkfun had it for 22
[02:26:10] <Eartaker> adafruit did
[02:26:21] <dioxide> ahh
[02:26:35] <Eartaker> ill order all else from mouser or digi
[02:26:55] <Xark> Looks like $4.30 from SFE and $5.95 from Adafruit for 328 chips.
[02:27:38] <Eartaker> or $2-3 from mouser or digi, plus I need a few other components
[02:27:52] <Xark> Eartaker: Cool. That works out then.
[02:28:19] <Eartaker> I bought a raspberry pi thinking it was going to be AWESOME... i really dont like that thing
[02:28:51] <dioxide> heh
[02:28:55] <Xark> I sure wish it had some real boot flash vs SD cards (which suck in my experience).
[02:28:59] <dioxide> if i had a rpi, id just make a mame box out of it
[02:29:22] <Eartaker> I use it for a SSH server so I can bypas proxies at work lol
[02:29:31] <dioxide> hah
[02:29:59] <Xark> Eartaker: Yep, my RPi is mostly a sshd "tunnel server" so I can access my home LAN from outside IPs (and also run squid etc.). :)
[02:30:32] <Eartaker> Xark: nice, all I do with mine now as well, it runs screen and irssi for me so I can stay on IRC
[02:31:46] <Xark> My PC and Mac "sleep" and then do a wake on lan when I connect from RPi. :)
[02:32:53] <Eartaker> nice
[02:36:56] <Eartaker> think this is worth it?
https://www.adafruit.com/products/174
[02:38:36] <Xark> Eartaker: I have it, with ZIP socket on it. Kinda nice, but hard to recommend for > $6 IMO. :)
[02:39:15] <Eartaker> hmm
[02:39:15] <Xark> Eartaker: If you are going to program a lot of AVRs and don't want to do it in your circuit, it might make sense.
[02:39:34] <Xark> Eartaker: However, not too much there to wire up in a breadboard. :)
[02:39:46] <Eartaker> true
[02:48:13] <Eartaker> so on digikey there are many atmega238p's... how do I know what one to buy for what im wanting to do
[02:48:25] <Eartaker> http://www.digikey.com/scripts/dksearch/dksus.dll?k=atmega328p&vendor=0&mnonly=0&newproducts=0&ptm=0&fid=0&quantity=0&PV143=37
[02:48:40] <Eartaker> http://www.digikey.com/scripts/dksearch/dksus.dll?vendor=0&keywords=atmega328p
[02:52:14] <OndraSter> look at datasheet, there are each models
[02:52:22] <OndraSter> those -AU, -PU etc mean packaging
[02:52:45] <Eartaker> ahh
[03:02:14] <Eartaker> ok about done with the order... other than the chip programmer and the resonator... do I need anything else for a basic AVR setup?
[03:02:29] <Eartaker> ordering sockets as well
[03:02:50] <OndraSter> 100nf caps?
[03:03:19] <OndraSter> and then basic stuff like buttons, LEDs, resistors
[03:03:32] <Eartaker> well I have all of that but what would the caps be used for?
[03:03:37] <OndraSter> you need 1k - 10k pullup resistor for the reset btw
[03:03:43] <OndraSter> for decoupling
[03:03:52] <Eartaker> resistors buttons and LEDS I have
[03:03:54] <OndraSter> if there is some surge in the supply (either way) the 100nf cap should filter it out
[03:04:05] <Eartaker> ahh
[03:04:55] <OndraSter> usually when you switch IO _|- or -|_ there is small surge as everything gets charged and the supply might drop a bit - the 100nf avoids that
[03:05:11] <OndraSter> plus I add 10uF per 2 or 3 VCC-GND pairs on my boards
[03:05:56] <Eartaker> ok ill order some caps
[03:08:46] <Eartaker> film or ceramic?
[03:25:45] <OndraSter> ceramic
[03:30:58] <zarhi> hello, can someone give me little advice for atmega8u2 and lufa troubles
[03:34:56] <abcminiuser> zarhi, I know a little about it, what's the issue?
[03:35:32] <zarhi> well, strange behavior with endpoint initialisation
[03:35:57] <zarhi> I need to init endpoints 0x02 and 0x04
[03:36:19] <zarhi> and endpoint 0x04 does not work...
[03:36:46] <zarhi> but: if I init endpoints 0x02, 0x03, 0x04 then everything works fine
[03:37:06] <zarhi> so, that is atmega limitation or what?
[03:38:23] <OndraSter> abcminiuser, you are a funny guy :D
[03:40:41] <abcminiuser> OndraSter, you're the first one to think so :P
[03:40:49] <abcminiuser> zarhi, which device?
[03:40:58] <zarhi> atmega8u2
[03:42:05] <abcminiuser> That's only got 176 bytes of EPRAM
[03:42:18] <zarhi> Endpoint_ConfigureEndpoint(0x02, EP_TYPE_BULK, 64, 1); Endpoint_ConfigureEndpoint(0x04, EP_TYPE_BULK, 64, 1);
[03:42:32] <abcminiuser> So if your total endpoint allocation sizes including the control one exceed that it will break
[03:42:39] <zarhi> and wireshark says for 0x04 error (-EPIPE)
[03:42:46] <zarhi> BUT:
[03:43:04] <zarhi> Endpoint_ConfigureEndpoint(0x02, EP_TYPE_BULK, 64, 1); Endpoint_ConfigureEndpoint(0x03, EP_TYPE_BULK, 64, 1); Endpoint_ConfigureEndpoint(0x04, EP_TYPE_BULK, 64, 1);
[03:43:14] <zarhi> and everything works as expected
[03:43:19] <abcminiuser> You're out of EPRAM
[03:44:11] <abcminiuser> How large is your control endpoint?
[03:44:18] <zarhi> 64 bytes
[03:44:41] <abcminiuser> Ok, so 64*3 is too large
[03:44:59] <abcminiuser> Your total allocations for endpoints on that device can't exceed 176 bytes
[03:45:33] <zarhi> the device works fine if I init this unneeded endpoint 0x03
[03:45:52] <zarhi> and does not work if I init only control + 0x02 and 0x04
[03:46:55] <zarhi> atmega8u2 datasheet says: control + 4 endpoints
[03:47:08] <zarhi> endpoint 1 and 2 are single banked, 64 bytes
[03:47:21] <zarhi> endpoint 3 and 4 are double banked 2x64 bytes
[03:47:31] <abcminiuser> *Up to* 64 bytes
[03:47:50] <abcminiuser> You are most likely confusing the crap out of the internal USB ram allocator module
[03:48:04] <abcminiuser> So while it appears to work, it's aliasing the endpoint memory so you'll get corrupt transfers
[03:48:23] <abcminiuser> You need to ensure that the total size of all endpoints does not exceed the physical amount of EPRAM in the device
[03:49:02] <zarhi> ok, but I test device for hours and it works fine
[03:49:09] <zarhi> no data corruption
[03:49:19] <OndraSter> I see that mega and xmega USB hardware stacks are completely, completely different
[03:50:13] <abcminiuser> Something has to have gone wonky, there is literally only 176 bytes of physical EPRAM in that device
[03:50:15] <zarhi> is there something that does require sequental endpoint adresses?
[03:50:26] <abcminiuser> So if you are exceeding that, something is being aliased incorrectly somewhere
[03:50:36] <abcminiuser> OndraSter, yes, very
[03:50:50] <abcminiuser> XMEGA uses the normal device RAM and an internal DMA rather than a hidden EPRAM
[03:50:58] <OndraSter> yep
[03:51:03] <OndraSter> I like DMA :D
[03:51:08] <abcminiuser> Don't we all
[03:55:53] <abcminiuser> zarhi, if you don't believe me, check with the LUFA guy, I'm sure he'll tell you the exact same thing
[03:56:54] <OndraSter> :D
[04:01:52] <zarhi> ok, I see: 3x64 > 176, so data received for endpoint 0x03 and 0x04 must be corrupted
[04:01:55] <zarhi> thats right?
[04:07:36] <abcminiuser> Yes
[04:07:49] <abcminiuser> Most likely the internal allocator is just wrapping around the end of the allocation
[04:07:56] <abcminiuser> But I've seen it do stranger things
[04:20:33] <OndraSter_> "I have got problem with alcohol, too. It costs too much."
[04:21:44] <zarhi> ok, so i need to move to atxmega
[04:22:00] <OndraSter_> xmega ftw
[04:22:16] <OndraSter_> what are you building?
[04:23:06] <zarhi> or try with lower endpoint size.... but don't know will that proprietary windows driver will accept that :(
[04:24:25] <creep> DanFrederiksen<< you can just hook up an perational amplifier in voltage fllower mode to buffer your adc input signal
[04:24:33] <creep> like lmc6482
[04:25:30] <creep> that will generate low impedance signal from your gigaohm output impedance signal
[05:30:35] <DanFrederiksen> creep, it can reliably read high impedance signals?
[05:35:22] <creep> sure
[05:35:49] <creep> with usually 1-3mV of offset
[05:36:51] <creep> it has typically 20fA input current
[05:36:58] <DanFrederiksen> http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/opampvar2.html
[05:37:06] <DanFrederiksen> femto??
[05:37:09] <creep> yep
[05:37:10] <DanFrederiksen> that's not a lot :)
[05:37:52] <DanFrederiksen> well that would allow me to avoid the wasteful high wattage resistor
[05:38:03] <creep> for some applications like 0-4V sensing, a simple LM358 will do
[05:38:11] <creep> it has around 350nA max input current
[05:38:46] <creep> because the input and output is not rail to rail
[05:39:04] <creep> hm, though you can get an LMV358 to get rail to rail output
[05:39:28] <creep> if you amplify your signal, then rail to rail input is not needed
[05:40:23] <DanFrederiksen> you mean they don't go to zero volt? how low do they normally go? it needs to work at least down to 1v
[05:40:48] <creep> no, the LM358 series can sense down to ground, but only go up to V+-1.5V
[05:41:22] <creep> they do go to zero volt if you put a 10k to ground from output for example
[05:41:33] <DanFrederiksen> ok, I basically need 0-5v
[05:41:54] <creep> that needs an RRIO opamp like LMC6482
[05:42:07] <DanFrederiksen> ok thanks
[05:42:33] <creep> it has 2 channels in one package
[05:44:32] <DanFrederiksen> ok. is there a single opamp package?
[05:44:41] <DanFrederiksen> not that it matters hugely
[05:46:16] <creep> yes there are
[05:46:36] <creep> search ti website for rrio single channel sot-23 package
[05:47:08] <creep> it has 5 pins and sot-23 fairly small
[05:47:17] <DanFrederiksen> gutti
[05:58:02] <creep> http://www.ti.com/product/lmc7101q-q1
[05:58:14] <creep> here is a single channel version of lmc6482 for example
[06:03:49] <creep> and this has a few microvolts offset
http://www.ti.com/product/lmp7731 ^^
[06:04:56] <DanFrederiksen> are TI ones best? or will any do
[06:05:23] <Horologium> TI makes good gear.
[06:05:27] <DanFrederiksen> :)
[06:06:08] <DanFrederiksen> I'm a little concerned with that frequency graph. that makes it look like it's only good for audio frequencies. or is that a misunderstanding
[06:06:25] <Horologium> are you going for higher frequencies?
[06:07:25] <DanFrederiksen> well, it's a 10-20kHz switcher and it has to watch a voltage ramp up linearly (current sensing) at say 0.2V/uS
[06:08:24] <Horologium> that could be an issue.
[06:08:58] <DanFrederiksen> so a ramp could be 10uS long and the value has to be fairly accurate at the 8th uS
[06:11:46] <DanFrederiksen> actually, digikey suitably has slew rate listed in V/uS and even the cheap slow ones are around 0.6V/uS which presumably means it wont be lagging much behind
[06:12:07] <DanFrederiksen> and there are faster opamps if needed. 22V/uS for instance
[06:13:03] <DanFrederiksen> so any will likely be fast enough. high frequency is only a problem for full amplitude sines
[06:13:32] <DanFrederiksen> and mine is a moderate speed ramp, right up opamp's alley it seems
[06:14:55] <DanFrederiksen> when the input currents are that extremely low, are they vulnerable to EMI?
[06:18:00] <Horologium> possibly
[06:18:10] <Horologium> will need some good circuit design.
[06:19:18] <Horologium> lots of ground planes and all that.
[06:23:18] <DanFrederiksen> I still don't know enough to do intelligent RF design. a ground plane under could just be an antenna config and make it worse :)
[06:24:29] <DanFrederiksen> if you understand RF it's the tiniest thing it takes to protect a chip input
[06:24:57] <RikusW> DanFrederiksen: download AppCAD
[06:25:08] <DanFrederiksen> RikusW, it can do RF sim?
[06:25:22] <RikusW> it can calculate trace impedances
[06:25:28] <RikusW> and a few other things
[06:25:34] <RikusW> and its free
[06:26:21] <Horologium> RF design....that's black magic of the worst and darkest kind.
[06:26:23] <RikusW> it seems groundplanes are quite important in RF design
[06:26:50] <RikusW> I did a 50 Ohm track for GSM, will see how it works when I get the boards
[06:27:22] <DanFrederiksen> hehe, RF is only considered black magic because the basic rules aren't known. and a good simulator to illustrate it isn't available
[06:28:19] <RikusW> parasitic inductances and capacitances is a headache
[06:28:44] <DanFrederiksen> sure, simple concepts like inductors and caps no longer exist
[06:29:15] <DanFrederiksen> but I like the empowering insight such thinking offers
[06:29:38] <Horologium> RF design was so much easier back when we used tubes.
[06:29:51] <DanFrederiksen> how so?
[06:29:59] <RikusW> like coax that is both a cap and inductor to from say 50Ohm
[06:30:17] <RikusW> *form
[06:30:47] <RikusW> DanFrederiksen: I built a little 1 transistor FM transmitter for 108MHz, but its _very_ unstable
[06:31:09] <Horologium> didn't have to worry about traces and whatnot....just point to point wiring and caps were the size of your thumb.
[06:31:17] <DanFrederiksen> RikusW, thermal noise?
[06:31:21] <RikusW> and there is microphonics too, tapping it on a table cause that sound to be broadcast without any mics attached
[06:31:39] <DanFrederiksen> :)
[06:31:43] <RikusW> DanFrederiksen: even bringing a finger close to it changes the frequency
[06:31:57] <RikusW> and its quite difficult to tune
[06:31:59] <Horologium> ooo..lack-o-shielding
[06:32:02] <DanFrederiksen> hehe, you'd actually think all RF circuits would be sensitive like that
[06:32:16] <RikusW> PLLs stablize them
[06:32:18] <Horologium> that's why we had those plastic screwdrivers for tuning TVs and radios back in the day.
[06:32:53] <RikusW> Horologium: its built in the air on the legs of the transistor :)
[06:33:00] <DanFrederiksen> but yes I suppose shielding becomes important to keep space from playing along
[06:33:19] <RikusW> and tiny too
[06:34:02] <DanFrederiksen> encase in blob of plastic and then metallize
[06:34:18] <DanFrederiksen> dunno :)
[06:34:24] <Horologium> I've built little transistor transmitters like that before..nifty little toys but that's about all.
[06:34:39] <RikusW> toys yes..
[06:34:52] <DanFrederiksen> surely there must be known good simple RF circuits
[06:35:13] <RikusW> PLL is simple, just an IC + VCO
[06:35:30] <Horologium> PLL is another level of black magic.
[06:36:01] <RikusW> I've connected and AVR to an old two way ROM based PLL
[06:36:11] <RikusW> radio
[06:36:33] <Horologium> AVR based AM transmitter! it actually works...
[06:36:33] <RikusW> mc145146, no longer easily available though
[06:36:37] <RikusW> FM
[06:36:44] <RikusW> at 60-80MHz
[06:37:14] <RikusW> that one is a dual modulus PLL
[06:37:20] <RikusW> clever idea
[06:37:23] <Horologium> would be nice to be able to make a tuneable FM transmitter and receiver.
[06:37:44] <creep> DanFrederiksen<< low cost opamps like lm358 has about 0.8-1V/us slew rate.
[06:37:47] <RikusW> and illegal too :-P
[06:37:49] <RikusW> afk
[06:37:51] <DanFrederiksen> I've considered a simple RF device to attach to stuff like a car that could answer at long distance when polled. for antitheft location
[06:37:53] <Malinuss> Horologium, for FM receiver, just buy one of the 1$ FM receiver IC's....
[06:37:56] <DanFrederiksen> something dirt cheap
[06:38:01] <RikusW> use GSM
[06:38:04] <creep> your adc is slower i guess
[06:38:07] <Horologium> RikusW, so long as it is below a certain power it is legal.
[06:38:11] <DanFrederiksen> GSM is not dirt cheap
[06:38:27] <DanFrederiksen> something you could attach to bicycle etc
[06:39:01] <creep> DanFrederiksen<< what is the point of using a 300MHz opamp for your 480kSPS adc ?
[06:39:49] <DanFrederiksen> I wasn't considering that fast. I just wanted to make sure it could reasonably follow a 0.2V/uS signal. and seems they all can
[06:41:20] <DanFrederiksen> would selecting an opamp with higher input current make it more noise robust? or doesn't it work that way
[06:41:50] <creep> no.
[06:41:59] <DanFrederiksen> picoamp is cool but if it's very sensitive then I could easily live with many nano amps instead
[06:42:31] <DanFrederiksen> hmm
[06:42:33] <DanFrederiksen> u sure?
[06:42:44] <creep> the difference is, veryhigh input impedance opamps use fet input stages, smalled input impedance ones use bipolar transistors
[06:46:00] <creep> good to see you know what you are doing :)
[06:46:32] <creep> btw i just read an atmel appnote on how to introduce noise into adc input to improve precision
[06:48:56] <DanFrederiksen> sounds counterintuitive :)
[06:49:24] <DanFrederiksen> unless you want to do sub digit precision
[06:49:48] <DanFrederiksen> by oversampling
[06:59:01] <RikusW> the GSM sim900 module I use cost about 20 Euro, or less in volume (1k = 14E)
[06:59:29] <RikusW> and its capable of taking custom fw as well
[06:59:32] <Horologium> but that requires a cellphone account to use.
[07:00:05] <RikusW> over here you can get a prepaid sim for 0.50E
[07:00:09] <DanFrederiksen> such is ok for more serious devices. I was just looking for a bare minimum locator device so you could attach it to all sorts of things
[07:00:13] <DanFrederiksen> for pennies
[07:00:49] <DanFrederiksen> ideally an unpowered device
[07:00:57] <RikusW> rfid ?
[07:01:00] <Horologium> long range RFID
[07:01:02] <DanFrederiksen> yeah basically
[07:01:12] <RikusW> Horologium: is there such things ?
[07:01:19] <DanFrederiksen> parabolic dish to sweep the horizon
[07:01:21] <Horologium> not really.
[07:01:23] <RikusW> usually its very short range
[07:01:25] <Horologium> but it could be.
[07:01:31] <DanFrederiksen> why not..
[07:01:50] <DanFrederiksen> unless it's a magnetic trigger
[07:02:00] <DanFrederiksen> in which case long distance is more problematic
[07:02:06] <DanFrederiksen> but surely RF is possible as well
[07:02:29] <Horologium> I have seen low power receiver that turns on a transmitter when it gets a certain signal.
[07:02:43] <Horologium> tracker that can't be tracked until you tell it to go active.
[07:02:51] <DanFrederiksen> precisely
[07:02:58] <DanFrederiksen> would be great for finding stolen stuff
[07:03:02] <DanFrederiksen> or babies :)
[07:04:29] <DanFrederiksen> maybe it could even be just a physical shape that responds to a very particular signal
[07:04:39] <DanFrederiksen> like ringing a crystal
[07:05:13] <Horologium> crystal radio that powers a transmitter.
[07:05:43] <DanFrederiksen> nah just a 'crystal' that rings
[07:05:57] <DanFrederiksen> like a tuning fork..
[07:06:07] <RikusW> nice DC/DC
http://dbaseserver.mistermail.nl/t/1279449/5051326/238214/0/
[07:06:31] <john_f> http://en.wikipedia.org/wiki/Thing_(listening_device)
[07:07:21] <RikusW> ah that one in Russia...
[07:10:20] <RikusW> http://cds.linear.com/docs/en/datasheet/8045fa.pdf
[07:10:25] <RikusW> its datasheet
[07:13:32] <RikusW> ugh, its bga...
[07:14:01] <creep> wirebond it
[07:16:29] <RikusW> its 50mil ball spacing
[07:16:46] <RikusW> I could attempt soldering that using a heatgun
[07:17:08] <RikusW> 5x8 pads
[07:17:33] <DanFrederiksen> bga requires minimum 4 layer pcb right?
[07:17:41] <creep> bga board amkingis harder than soldering them ;)
[07:17:47] <creep> *making is
[07:18:01] <Horologium> schmartboards
[07:18:10] <creep> DanFrederiksen<< no and it depends
[07:19:04] <DanFrederiksen> yeah I guess if it's only 4 rows deep you can do it with 2 layer. or super thin paths
[07:19:44] <creep> not really cool to use superthin path under bga
[07:19:54] <RikusW> that one's pad arrangement will allow easier routing
[07:21:10] <creep> Horologium<< i have routed a line zigzag style between leads of soic, you wouldn't like to solder that, or create the pcb :)
[07:22:44] <RikusW> that bga at 1.27 will allow 200um (8mil) tracks + spacing between balls
[07:22:58] <RikusW> just doable
[07:23:04] <Horologium> hehe.
[07:23:25] <creep> RikusW<< yeah and now you will fight solder bridges
[07:23:28] <Horologium> schmartboard has a solder-through bga board.
[07:23:31] <Horologium> several actually.
[07:23:35] <RikusW> though there is only one pad requiring it on that IC
[07:23:58] <RikusW> Horologium: with via's beneath pads ?
[07:24:04] <Horologium> yup.
[07:24:14] <RikusW> I had the same idea :)
[07:24:21] <Horologium> think they patented it.
[07:24:38] <RikusW> can't prevent me from making it for myself
[07:24:48] <Horologium> their tqfp boards are interesting...the solder mask is real thick between the leads...so the chip sits in place
[07:25:04] <RikusW> I've seen a vid of that
[07:25:14] <Horologium> then you just touch soldering iron to the trace and the solder that is already on it flows up under the leads.
[07:25:38] <creep> Horologium<< i used to do that without a mask
[07:25:54] <Horologium> the thick mask holds the leads in place.
[07:26:07] <creep> tweezers, or glue holds it in place too
[07:26:19] <Horologium> holds in place and aligns things.
[07:26:26] <creep> or, surface tension of solder centers the tqfp during reflow
[07:28:08] <creep> well designed nsmd pads will center components too.
[08:51:43] <creep> now where did i put my parallel port connectors ;/
[10:28:08] <MrMobius> theBear, i think KS0108 is the chip you were trying to tell me about the other day
[10:29:19] <Horologium> ks0108 is a graphic lcd controller, yes?
[10:29:33] <MrMobius> yeah
[11:07:49] <abcminiuser__> Woo, I have my Mass Storage bootloader running on the 32U4
[11:07:55] <abcminiuser__> The code is hideous tho
[11:12:39] <Malinuss> abcminiuser__, can you format it to a file system and store things?
[11:13:09] <abcminiuser__> No, it's emulating FAT, so you can only reprogram the device by overwriting the generated virtual file
[11:14:06] <Malinuss> abcminiuser__, I see, cool
[11:14:31] <abcminiuser__> Malinuss,
http://fourwalledcubicle.com/blog/2013/03/the-new-new-lufa-bootloader/
[11:22:51] <OndraSter> abcminiuser__, how big is it compiled?
[11:23:28] <abcminiuser__> Well, 6KB
[11:23:38] <OndraSter> that does not fit bootloader section, does it :D
[11:23:44] <abcminiuser__> But with the horror I've just created, it will work on a device configured for 4KB
[11:23:57] <abcminiuser__> I create a new section of 2KB before the real space, with a trampoline over it
[11:24:02] <abcminiuser__> Then fill that with the excess code
[11:24:07] <OndraSter> mega*u* does not have special space for BL does it?
[11:24:08] <OndraSter> as xmega
[11:24:11] <OndraSter> aka 32+4
[11:24:20] <abcminiuser__> No it takes up the regular FLASH space
[11:24:35] <OndraSter> sucks
[11:24:39] <abcminiuser__> Ja
[11:24:42] <OndraSter> 32-6... 26kB...
[11:24:48] <abcminiuser__> Well this works, but I'm not sure I want to release it...
[11:42:57] <abcminiuser__> Ok, who's got an Arduino Leonardo and an external programmer?>
[11:52:33] <Malinuss> abcminiuser__, eh I have a teensy 2 (atmega32u4) and a external programmer....
[11:53:52] <abcminiuser__> Want to test?
[11:54:15] <Malinuss> abcminiuser__, depends how interesting I find it ;P
[13:26:05] <creep> hi
[14:07:29] <tzanger> afternoon
[14:17:53] <Steffanx> lo
[15:15:37] <rue_house> abcminiuser__, !
[15:15:43] <rue_house> welcome back!
[15:16:20] <abcminiuser__> Hey hey rue_house
[15:16:26] <abcminiuser__> I have actual, real world internet now
[15:16:31] <abcminiuser__> New place, fiber connection
[15:16:36] <Tom_itx> WOOT!
[15:16:38] <abcminiuser__> So I'm back for good
[15:16:44] <Tom_itx> did you move?
[15:16:57] <abcminiuser__> Last month
[15:17:07] <abcminiuser__> My old apartment got sold
[15:18:09] <rue_house> cool
[15:18:53] <rue_house> you going to hang out be idle long term?
[15:19:14] <abcminiuser__> I've been idling here nearly two months now :(
[15:19:19] <rue_house> cool
[15:19:23] * abcminiuser__ is invisible yet again
[15:19:25] <rue_house> yea, I'm an attentive admin
[15:19:54] <abcminiuser> Well it's good to see my connection still works :P
[15:20:05] <abcminiuser> With real internet I don't get dropouts like on the old public Wifi
[15:20:19] <abcminiuser> Tom_itx, want a Mass Storage class bootloader for the USB AVRs?
[15:20:35] <abcminiuser> I've got it running on the smaller devices, but it's 6KB
[15:21:22] <OndraSter> push it to the limit..
[15:21:39] <Tom_itx> sure
[15:22:00] <Tom_itx> what do you use for the 'mass' ?
[15:22:10] <abcminiuser> The device flash
[15:22:24] <Tom_itx> add sd to it :D
[15:22:24] <abcminiuser> So y'all don't see me here, read my blog posts...
[15:22:32] <abcminiuser> Damn, I AM invisible
[15:22:42] * abcminiuser strips off clothes and runs around
[15:23:34] <Tom_itx> is it in the git?
[15:23:55] <abcminiuser> For the 128KB and 64KB devices yes
[15:24:03] <abcminiuser> For the smaller ones not yet, since the code is kinda fugly
[15:24:13] <abcminiuser> I had to make some linker gymnastics to make it work
[15:24:55] <OndraSter> abcminiuser, is it possible from within atmel studio to build for multiple devices at once?
[15:25:18] <abcminiuser> Technically you could make it use an external makefile and do it that way...
[15:25:27] <OndraSter> too hard :)
[15:25:30] <abcminiuser> But the GUI is one-device-per-project centric
[15:25:38] <OndraSter> oh well, I will release one firmware for 128kB and one for 256kB devices
[15:25:45] <abcminiuser> Use links and several projects, that link source files?
[15:25:55] <OndraSter> hmm will see
[15:26:08] <OndraSter> I like how on xmega all the register positions etc are all the same
[15:26:09] <OndraSter> and peripherals
[15:26:14] <OndraSter> so I can flash the code from a3u to a1u
[15:26:19] <abcminiuser> Indeedy
[15:26:19] <OndraSter> (as long as it matches the flash size)
[15:28:18] <OndraSter> I want to get old. Why? Because I won't hear high pitch noise and I won't hear my PC squeaking while in idle :(
[16:04:47] <rue_house> is nobody going to make anything with the BF interperter I put an on avr?
[16:05:16] <rue_house> OndraSter, change your power supply?
[16:06:21] <Malinuss> BF interpreter ?
[16:08:19] <kdehl> I've seen a bunch of docs on how to generate different video signals with an AVR, but how about receiving? Like, can I use an AVR to receive a VGA or NTSC (or PAL or whatever) signal and drive an LCD?
[16:10:12] <creep> a 16x1 lcd with the input color? :)
[16:11:01] <kdehl> Point is, it's too slow, huh?
[16:11:03] <kdehl> Heh.
[16:11:23] <creep> sure you can do that, get a fast adc, and a 32 bit avr
[16:13:02] <kdehl> Hm. Yeah.
[16:13:09] <creep> and don't confuse compisite video with vga
[16:13:13] <Malinuss> creep, why not just use a STM32 or whatever?
[16:13:18] <creep> vga has RGBHV input
[16:13:27] <Malinuss> isn't 32bit avr like dead ;D
[16:13:34] <kdehl> Right. I don't know anything about PAL or NTSC, I must admit.
[16:13:35] <creep> i thought it is new
[16:13:42] <creep> 1.5 mips at 1MHz
[16:15:44] <kdehl> Hm. But could you just make a FPGA to drive an LCD from an NTSC signal?
[16:15:54] <jacekowski> kdehl: PAL is two signals together b/w for older TVs + colour
[16:16:03] <kdehl> Hm, okay.
[16:16:11] <jacekowski> same for NTSC
[16:16:15] <kdehl> I see.
[16:16:19] <jacekowski> and then there is SECAM
[16:16:44] <jacekowski> kdehl: and decoding colour part is fairly easy with dedicated circuitry, but in slow AVR it's fairly complicated
[16:17:35] <kdehl> Right, but an FPGA could be quite fast, if I understand it correctly. Then you mightn't need an AVR at all, right?
[16:18:16] <jacekowski> yes
[16:18:19] <kdehl> I should read up on this, I feel.
[16:18:28] <kdehl> Interesting.
[16:19:01] <jacekowski> basically, PAL/NTSC/SECAM and few others is just an addon to old B/W standard
[16:19:19] <kdehl> Idea: put an LCD on a NES cart, plug a cable from the RF connector on the back of a toploader NES, and run the NES "without" a screen.
[16:19:25] <kdehl> jacekowski: I see.
[16:19:44] <kdehl> That's how it's backwards compatible, I assume.
[16:20:32] <jacekowski> in that case it's a lot more complicated
[16:20:43] <jacekowski> because you have to demodulate that RF signal in first place
[16:21:33] <kdehl> Hum hum... this has something to do with the channel the signal is on?
[16:21:55] <jacekowski> yes
[16:22:20] <kdehl> I've always wondered how you can transmit different channels on the same medium in PAL, NTSC and the likes, but not on VGA, for example.
[16:22:46] <kdehl> This has to do with this modulation thing then?
[16:22:52] <jacekowski> ues
[16:22:54] <jacekowski> yes*
[16:23:12] <kdehl> Alright.
[16:23:58] * kdehl goes Wikipedia
[16:24:18] <OndraSter> rue_house, well, it is the GPU :P
[16:24:24] <OndraSter> not power supply
[16:24:30] <OndraSter> powersupply on the GPU
[16:24:40] <kdehl> jacekowski: But this modulation thing could also be done through a FPGA?
[16:24:59] <kdehl> I mean, it'd always be on the same channel...
[16:33:46] <jacekowski> yes and no
[16:34:00] <jacekowski> kdehl: read up about something called Software Defined Radio
[16:34:00] <creep> lol?
http://www.schmartboard.com/index.asp?page=products_partnum&id=124
[16:34:26] <jacekowski> kdehl: that's modulation/demodulation done in software
[16:35:34] <kdehl> jacekowski: Will do! Thank you very much!
[16:35:50] <jacekowski> creep: kinda neat
[16:36:34] <creep> jacekowski<< i thought it is lame
[16:36:34] <jacekowski> creep: it means you can solder components with one hand and no other tools than soldering iron
[16:37:03] <jacekowski> when you solder through hole you really need 3 hands
[16:37:29] <creep> or just bend a leg and use a pcb holder.
[16:37:47] <jacekowski> then you need 2 hands
[16:37:48] <creep> and if you use solder paste, then you may solder with 1 hand
[16:37:56] <jacekowski> one to feed the wire and one to heat it up
[16:38:21] <creep> do you usually solder with one hand while eating a sandwich ?
[16:38:31] <jacekowski> yes
[16:38:58] <jacekowski> it would be waste of time not to multitask
[16:40:13] <vsync1> i usually solder with my toes
[16:40:26] <rue_house> audiable noise off the gpu's internal power supply?
[16:40:31] <rue_house> time for a new one
[16:46:48] <creep> rue_house<< mine does that too, but it is no problem.
[16:48:03] <creep> noise is caused by mechanical variations caused by rapid heating/cooling, and fast current change
[16:49:35] <creep> my sd-ram made a 20kHz+ whizzing noise when working hard 15 years ago
[16:51:10] <creep> and a ceramic capacitor is like a piezo speaker when loaded with current spikes
[17:19:03] <kdehl> jacekowski: I found a chip,
[17:19:05] <kdehl> TDA3566A PAL/NTSC decoder
[17:19:28] <kdehl> What does it do, really? I try to read the data sheet, but I don't understand much of it...
[17:19:41] <kdehl> Is it just an analyser or something?
[17:20:09] <kdehl> Nothing that I could use, I guess.
[17:21:21] <timemage> kdehl, well, it seems to split the signal into subcomponents.
[17:22:44] <kdehl> Hm. Okay.
[17:22:58] <kdehl> Well, I guess I have tons to read up on before I can embark on such a project, heh.
[17:24:09] <kdehl> I'm goint to try to make a version of this VGA adapter first to get the hang of the basics of video transmitting.
[17:24:12] <kdehl> http://www.lucidscience.com/pro-vga%20video%20generator-1.aspx
[17:24:20] <kdehl> Then I might move on to NTSC.
[17:24:39] <kdehl> Or are VGA and NTSC so different that it's just a waste of time, perhaps?
[17:25:02] <kdehl> I read it through, I think I understand how it works.
[17:29:58] <Malinuss> kdehl, take a look at this:
https://code.google.com/p/arduino-tvout/ for NTSC/PAL and take a look at this:
http://www.lucidscience.com/pro-vga%20video%20generator-1.aspx for VGA
[17:30:07] <timemage> kdehl, been a while since i read about the differences. similar concepts. vga should be a lot easier to work. dedicated sync lines, colors already seperated out.
[17:30:42] <jacekowski> kdehl: vga is easy
[17:30:50] <jacekowski> kdehl: because all signals are already in separated easy to eat form
[17:31:02] <kdehl> Right. I'll start with VGA, then.
[17:31:26] <kdehl> Ah, so that's what I might need that chip for later when I get to NTSC?
[17:31:46] <Malinuss> if you check my links it's even easier
[17:31:58] <kdehl> Malinuss: Absolutely.
[17:32:20] <kdehl> Malinuss: Right, the VGA link is the one I plan to follow.
[17:33:07] <kdehl> And the NTSC/PAL seems to be similar to the VGA link, only.. well, NTSC/PAL!
[17:33:16] <timemage> kdehl, depends on what you want to do. if you want to generate a black and white text display you don't need a chip like that at all. that chip seems geared toward decoding as though you wanted to capture frames or send them to crt hardware.
[17:34:25] <kdehl> Right. I want to capture the signal.
[17:34:40] <kdehl> But first I should learn how to generate one, I think. It somehow feels easier.
[17:35:06] <kdehl> And fun! It'd be awesome to have a low-resolution VGA terminal for my AVR!
[17:38:25] <kdehl> I love that hardware setup of the NTSC link. Two reistors!
[17:41:58] <Xark> Fun stuff. I managed to get it to do "text mode" (which makes for much higher res when dealing with ~2K RAM). :)
http://imgur.com/a/JO4Cq
[17:43:31] <kdehl> Xark: You used the arduino-tvout thing?
[17:44:48] <Xark> kdehl: Same hardware (but re-written code).
http://imgur.com/a/YmlWf/noscript#0 I also had it generating audio during the display ->
http://imgur.com/a/qPis6#3
[17:45:34] <kdehl> Right, so no Arduino stuff. Nice.
[17:46:20] <Xark> kdehl: It will build/run as an Arduino library if desired, but not calling any of their functions. :)
[17:48:02] <kdehl> Hehe.
[17:48:06] <Xark> The video generation is mostly asm (called via interrupt every scan line), but the "console code" (printing, scrolling, newline etc.) is in C.
[17:52:18] <Casper> asm due to the tight timing requirement
[17:52:57] <kdehl> Uh, we're talking about NTSC here, right?
[17:53:05] <kdehl> The VGA project did exactly the same.
[17:53:23] <kdehl> Had to count how many cycles each instruction takes in order to make the timing perfect.
[18:29:34] <Xark> Yeah, very similar, just VGA is higher frequency (and easier to get color). Here is a VGA project I did with an STC 8051 @ 36Mhz (probably could do this on 20Mhz AVR). :)
http://imgur.com/nDceh
[18:29:40] <Malinuss> test
[18:30:08] <Xark> Malinuss: test successful. :)
[18:30:25] <Malinuss> yay
[18:31:27] <Horologium> Xark, you do a lot of microcontroller-vga work?
[18:32:01] <Xark> Horologium: Well, I can't help but see MCUs as retro video game consoles. :) However, I don't know about a "lot"....
[18:33:46] <Horologium> hehe.
[18:34:01] <Horologium> I have a current ongoing project that is a retro video/computer console.
[18:34:10] <Horologium> work on it bits and pieces here and there.
[18:34:38] <Horologium> currently working on getting stable 800x600 vga output using some serial sram chips and an avr.
[18:35:19] <Horologium> http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en559066 serial sram that can clock out at 20MHz...by interleaving them I can get 40MHz pixel frequency.
[18:35:50] <Horologium> by using 4 I can use 2 for display while writing to the other then swap them...giving me a bank switched display.
[18:39:29] <Malinuss> Horologium, yeah double buffering is the only way to go ;D
[18:40:10] <Horologium> yup.
[18:40:34] <Xark> Horologium: Sounds neat. 800x600 is pretty nice to squeeze from that.
[18:40:53] * Xark has been "cheating" by playing with FPGAs recently...
[18:41:06] <OndraSter> tbh I would just shove DVI data nowadays :)
[18:41:10] <Horologium> I'm trying to do this whole thing with a minimum of soldering...all on solderless breadboards.
[18:41:10] <OndraSter> in FPGA
[18:41:49] <Horologium> whole system with ethernet, sd card for programs, a basic OS like the old c-64, etc..
[18:42:27] <OndraSter> are you going to write an interpreter for the AVR? :P
[18:42:32] <OndraSter> Basic
[18:42:38] <OndraSter> with 80x25 console
[18:43:00] <Malinuss> Horologium, but why would you want that high resolution (not trolling)? I mean, if you ever want to write games for it/make people write games for it, they would propalby prefer proper retro-graphics resolution? I'm what one could call a amature game developer and I sugest lower resolution ;D
[18:43:32] <Malinuss> or do you offer some scaling modes?
[18:43:35] <OndraSter> there is already AVR based console
[18:43:40] <Horologium> easily convertable to 640x480.
[18:44:22] <Horologium> part of this is to eventually write an actual web browser and irc client in basic for the thing...hehe
[18:44:29] <OndraSter> haha
[18:44:45] <OndraSter> good luck mate
[18:45:04] <Horologium> irc client is doable...simple web browser harder but doable I think...specially if I use lynx as a basis.
[18:45:10] <OndraSter> just base it on xmega -- I can offer you dev board that can go to breadboard. 256kB flash, 16kB RAM...
[18:45:15] <OndraSter> DMA, everything
[18:45:28] <OndraSter> plus 32MHz without overclocking
[18:45:40] <Horologium> but, what you don't have is the ability to run code from sram..
[18:45:46] <OndraSter> nope
[18:45:49] <OndraSter> I thought you were using AVR?
[18:46:07] <Horologium> actually using 3 different processor types.
[18:46:38] <Horologium> AVRs for the video generation, sound, and aux processing.
[18:46:43] <Horologium> 8051 for the CPU
[18:46:47] <OndraSter> ah
[18:46:56] <Horologium> and PIC for USB interface.
[18:47:04] <OndraSter> why not run java virtual machine on AVR? and load apps from SD card
[18:47:06] <OndraSter> (lol)
[18:47:12] <Horologium> slow..
[18:47:15] <Xark> Horologium: Interesting choices. What kind of 8051?
[18:47:20] <Horologium> ds89c450
[18:47:22] <Horologium> from maxim/dallas
[18:47:50] <Horologium> I know, expensive, but that's what I have handy and available.
[18:48:57] <Horologium> I also have some maxim parallel nvsram chips that I've interfaced to it...with some bank switch magic I can get lots of memory packed in and around 64K address space...
[18:49:24] <Horologium> can even overlap program and data spaces or have them in separate sections of the memory.
[18:49:31] <OndraSter> why not use Z80?
[18:49:36] <OndraSter> didn't Z80 have 20bit addressing?
[18:49:46] <OndraSter> or was it 8086 only?
[18:49:46] <Horologium> probably, but I don't have any z80 chips here.
[18:49:54] <Xark> Nice. 8051 starts looking pretty decent with single-cycle variants. :) That STC in my design is dirt cheap but quite similar.
[18:50:17] <Horologium> yeah..I was looking at the STC the other day..maybe yesterday..something like that.
[18:50:27] <Horologium> they are very similar...
[18:52:01] <Horologium> if AVR had a dip package USB-otg capable chip and the ability to run code from an external sram chip I would go all AVR...but, alas.
[18:52:28] <Xark> I actually got a 68000 64-pin DIP (huge), but nowadays I am thinking more soft-core in FPGA for CPU for my "retro console" design. :)
[18:53:03] <Horologium> have a pile of those.
[18:53:12] <Horologium> even have some 68000 boards...
[18:53:20] <Horologium> nifty old learning systems.
[18:53:28] <OndraSter> yay
[18:53:36] <Xark> Was reading up on it. Seems a bit tricky to wire up on a breadboard (when one is used to AVR). :)
[18:53:37] <OndraSter> why not use the "GPU" from NES? :D
[18:53:44] <Horologium> got them for one dollar each...think I have 10 or 12 of them.
[18:53:46] <Tom_itx> yep, i had a 68332
[18:53:50] <Tom_itx> still do actually
[18:53:58] <OndraSter> :( where one gets such sales?
[18:54:08] <Horologium> university surplus sales auction.
[18:54:20] <OndraSter> oh
[18:54:52] <OndraSter> our university uses some PIC Starter Kit
[18:54:57] <OndraSter> it has got some pic24f...stuff
[18:55:07] <OndraSter> + OLED + RGB LED + basicstuff
[18:55:22] <OndraSter> and then we use Digilent Basys 2 with Spartan3E FPGAs
[18:55:26] <OndraSter> and then AVR Butterfly :D
[18:55:31] <Xark> I think my 68000-10Mhz chip is a "pull" from Jameco ($9). :)
[18:55:44] <OndraSter> I have got here bunch of 8051/31/32 and Z80s
[18:55:48] <OndraSter> with some peripheral chips
[18:55:52] <OndraSter> some desoldered, some on boards
[18:56:50] <OndraSter> isn't 8051 the oldest living core btw?
[18:56:55] <Horologium> considering ripping apart the bunch of C64 machines I have here.
[18:57:12] <Horologium> oldest still in full production, probably.
[18:58:42] <Xark> OndraSter: According to Wikipedia, PIC is older (1975 vs 1980).
[18:59:17] <timemage> iirc, the z80 is older than the 8051 also. didn't know if maybe we wasn't considering it as "living"
[18:59:58] <Xark> 8048 was 1976 (and I think 8051 is like that as 8086 is to 8085).
[19:00:19] <Horologium> is z80 considered a microcontroller though? or a microprocessor?
[19:00:33] <Xark> Horologium: It has MCU varients.
[19:01:31] <Horologium> so does the 6502
[19:01:40] <Horologium> aka the 6510 which is used in the C64.
[19:01:49] <Horologium> has a GPIO port on it.
[19:03:11] <Xark> Yep. I have a 65C02 I purchased recently for cheap that can do 14Mhz (this was new, as they still make them). Apparently 6502 has a small niche for embedded systems where they want an external address bus (say for custom hardware, ROM, RAM).
[19:03:14] <Horologium> that's how they got more than 64K of total memory in the C64...64K of ram plus lots of rom.
[19:03:23] <Horologium> the gpio controlled the bank switching.
[19:04:06] <Xark> Horologium: Yeah, I remember. Fun system. I shipped several commercial games for C64 (as well as other 8-bits like Apple, Atari).
[19:04:35] <Horologium> taught myself assembly on the 6502 using a vic-20 and peek/poke.
[19:04:41] <Horologium> then got a vicmon cartridge!
[19:05:57] <OndraSter> Horologium, I dare you to tear them apart
[19:06:23] <Xark> Horologium: Right on. My first system was very much like a black & white VIC-20 (4K RAM + MS BASIC). Ohio Scientific C1P ->
http://www.obsoletecomputermuseum.org/challege/
[19:06:32] <Horologium> not sure if they would be worth more on ebay hole or as parts to play with.
[19:06:38] <OndraSter> restore them.
[19:06:39] <Xark> Horologium: I soldered joysticks to it. :)
[19:06:42] <OndraSter> or send them to me
[19:06:57] <Horologium> nothing to restore...far as I know they all work.
[19:07:11] <OndraSter> oh
[19:07:12] <OndraSter> even better
[19:07:30] <Horologium> so does my vic-20
[19:07:34] <Horologium> which goes NOWHERE!
[19:07:34] <Horologium> hehe
[19:08:48] <OndraSter> C64 and such are sold here for quite a lot money still
[19:08:55] <Horologium> oh?
[19:09:02] <Horologium> one is a c64c
[19:10:11] <OndraSter> hell I sold Atari 800XE + casette reader + joystick for like $60 not so long time ago
[19:10:17] <OndraSter> the atari + casette reader were working
[19:10:21] <OndraSter> no idea about the joystick
[19:10:40] <OndraSter> the casette reader was even in original package, it seemed like it was never used
[19:10:52] <OndraSter> the atari had only original box, no manuals though
[19:10:54] <OndraSter> (all wires)
[19:10:57] <Xark> Horologium: The C64C was a nice "cleaner" version. One of the sad things about the C64 was the "glitchy" display (sparkle etc.). In commercial games you could not use hardware sprite collision because it would give false answers on many machines due to glitches. :)
[19:11:28] <OndraSter> thanks for making me feel so young! :D
[19:11:45] <Xark> All too easy these days. :)
[19:11:52] <OndraSter> I started gaming on 386? 486? with TTD, Ducktales...
[19:12:37] <OndraSter> which was fun because it was all in english :P
[19:13:04] <Xark> Hehe. I didn't switch from my Amiga 1000 until 1992 or so when I could put Linux on a 386 (but I did play Doom and Wolf3d etc. in DOS).
[19:13:25] <Horologium> Xark, ever see the amiga 2000UX?
[19:13:37] <Horologium> an amiga 2000 with a hardcard and unix on it.
[19:13:43] <Horologium> and an accelerator card.
[19:14:40] <Xark> Horologium: I know of it, but never used it. I have a developers A1000 and first saw an Amiga behind the curtain at the CES joystick booth. :)
[19:17:11] <Xark> Horologium: There was a time I wanted one, but I doubt it would be much fun to play in Amiga Unix these days. I would rather have a NeXT cube if I were looking for an ancient 68K Unix box. :)
[19:17:49] * Xark has an A3500 and a SGI Indy gathering dust in the garage still...
[19:22:57] <OndraSter> SGIs are cool
[19:22:58] <OndraSter> were
[19:24:41] <Xark> Indeed. I used the Indy has a cool looking monitor stand for a few years even. :)
[19:24:49] <Xark> as a*
[19:25:54] <Xark> MIPS is a neat architecture too.
[19:31:50] <Roklobsta> I saw my 1st 3D desktop and Max Headroom in 3D on an SGI. Now my cheap arse phone can do way better.
[19:54:36] <Malinuss> this circuit should work like a nice digital pot, right?
http://i.imgur.com/DD9Sg4B.png
[19:55:15] <tzanger> Malinuss: no
[19:55:22] <Malinuss> tzanger, no?
[19:55:24] <Malinuss> ;D
[19:55:26] <tzanger> no.
[19:55:34] <Malinuss> tzanger, ok :(
[19:55:48] <Malinuss> tzanger, now you might want to elaborate :)
[19:55:53] <tzanger> I think you're misinformed about how a transistor works
[19:56:44] <tzanger> you might want to google for an R2R DAC; that gives you a current output which would more closely approximate a digital pot
[19:57:15] <tzanger> you can leave the left hand side of the circuit alone and replace the transistor mess with a classical R2R DAC section
[19:58:50] <Malinuss> tzanger, neverless I can't see why my setup wouldn't work? Since the BJT have no resistance (more or less none), the current wouldn't travel trough the resistor?
[20:00:14] <tzanger> a transistor will turn on when it's base-emitter voltage rises above ~0.7V, and it will allow a current of the base current * the transistor's hfe (gain) to flow between the collector and emitter
[20:00:43] <Malinuss> tzanger, exactly... so no current would travel over the resistor
[20:00:45] <tzanger> your "bit 0" transistor, for example, has an equivalent of 12k7 between its emitter and common
[20:01:10] <Malinuss> yes
[20:01:42] <tzanger> that means that your base drive voltage must overcome the 0.7V of the transistor b-e junction plus whatever voltage is dropped across that 12k7, which depends entirely on how much current is present at the base plus the input
[20:01:56] <tzanger> if you don't believe me, load it up in circuitlab and simulate it
[20:01:59] <tzanger> just two bits
[20:02:14] <tzanger> it's not the equivalent of a digital pot at all
[20:02:35] <tzanger> a transistor isn't like a relay which simply shorts the c-e junction when there's base voltage
[20:03:02] <Horologium> mosfet time!
[20:03:06] <Malinuss> I do belive you, I just want to understand it too. I will do some testing
[20:03:06] <Horologium> but, even that might have issues.
[20:03:17] <tzanger> why not eliminate all those transistors and build a standard R2R DAC? it's 8 less transistors and your 8 1k resistors will have to change
[20:03:37] <Malinuss> tzanger, I guess you are right
[20:03:41] <tzanger> you have one end tied to ground, so you essentially want a programmable current sink
[20:03:51] <tzanger> an R2R DAC will do that for you, more or less
[20:04:01] <Horologium> but will be a source, not a sink, yes?
[20:04:07] <Malinuss> ^
[20:04:12] <Malinuss> and I need a sink
[20:04:24] <Malinuss> since the pins will be high
[20:04:43] <tzanger> If you want to make it really nice, you would use one transistor configured as a constant current sink and your R2R would dial in the current
[20:04:52] <tzanger> or if you wanted to be really slick you'd use two transistors in a current mirror configuration
[20:05:33] <tzanger> if you want a source and a sink you could use a single opamp with enough source/sink capability to do the job and have it essentially "regulate" the load
[20:05:38] <Malinuss> tzanger, then I would just need 8 transistors and 8 resistors, right?
[20:05:47] <tzanger> but if you wanted to do that you could probably get away with using an R2R to feed the ADJ pin of an LM317
[20:05:47] <Horologium> one transistor.
[20:05:51] <tzanger> Malinuss: no, one
[20:05:53] <Horologium> and a bunch of resistors.
[20:06:05] <Horologium> use the resistor r2r ladder to drive the base of the transistor.
[20:06:13] <tzanger> 16 resistors, one transistor: programmable constant current sink (or source, dpeending on how you hook it up)
[20:06:52] <Malinuss> tzanger, where would the BJT be connected in such a setup?
[20:07:00] <Horologium> or 24 resistors if they are all the same value.
[20:07:00] <Malinuss> oh nvm
[20:07:01] <tzanger> Malinuss: google for "constant current sink"
[22:48:55] <DanFrederiksen> atmel has no micros that have multiple ADCs that can sample at MHz so you can just read them as a register and the value is always there?
[22:49:30] <DanFrederiksen> this shared ADC and huge latency is bs
[22:51:20] <DanFrederiksen> they should have 4 ADCs each 1MS/s plus they should have various side registors with running averages
[22:58:13] <Casper> DanFrederiksen: 20MHz is not enought to deal with that many ADC and that many samples
[22:58:37] <Casper> if you need more, just get some external ADC
[22:58:42] <Casper> and move to FPGA
[22:59:49] <DanFrederiksen> Casper, doesn't have to deal with them. just has to be able to read them whenever the code so desires
[23:01:04] <DanFrederiksen> it would also be acceptable if the ADC could respond in a microsecond
[23:02:02] <DanFrederiksen> but 13-26 clock cycles, that's bullshit
[23:02:24] <Casper> if you say so
[23:02:33] <DanFrederiksen> if the chip costs more to have proper ADC then that's fine with me
[23:03:25] <DanFrederiksen> at least have it as an option. because power electronics doesn't wait 26 microseconds to explode
[23:04:20] <Casper> there is no reason to make an ADC that fast in AVR, and if you want to make a SMPS, then you don't want to make it based on a microcontroller, very bad design and idea
[23:05:54] <DanFrederiksen> we are moving to uC control and away from analog. so no it's not a bad idea to have fast software
[23:06:19] <Casper> analog is still there to last for a very long time
[23:06:39] <Casper> SMPS is a special field, and is not to be made with a general purpose microcontroller
[23:06:41] <Casper> however
[23:06:53] <Casper> some attiny does have proper smps hardware
[23:07:11] <Casper> which, btw, do not rely on ADC
[23:07:21] <Casper> ADC isn't suited for SMPS
[23:22:35] <DanFrederiksen> Casper, and why not?
[23:23:07] <Casper> the range is too small
[23:23:18] <Casper> and it add too much delay, even if you could read it instantly
[23:23:25] <Casper> the code is too slow
[23:24:33] <Casper> you want to have like 200 distinct value between 2.49 and 2.51, or 20mV... and even that is considered bad for a smps
[23:25:27] <Casper> a general purpose ADC, even a 16 bits one, will not be able to provide enought usefull resolution
[23:25:41] <Casper> and will have issues with noise
[23:26:02] <Casper> adding a capacitor to make a low pass filter will partially fix the issue, but then the lag will be an issue
[23:26:16] <Casper> so the proper way is to hav
[23:26:31] <Casper> so the proper way is to have an analog section with specialised IC to do the smps
[23:26:45] <Casper> and optionally a microcontroller that set it up
[23:58:50] <jadew> which tiny is good for smsps?
