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[00:39:19] <rue_shop5> how do I switch a tiny13 from 1Mhz to 10Mhz?
[00:43:59] <Casper> with a crystal? :D
[00:44:53] <rue_shop5> oh there, the motors limit is acutally the 700Hz, the irq stops responding at 15Khz
[00:44:55] <rue_shop5> that'll do
[00:45:12] <rue_shop5> there is a flag or fuse to speed up the t13
[01:53:26] <inflex> crank the OSCCAL up?
[02:02:17] <rue_house> no there is a switch
[02:02:28] <rue_house> one that controls the main divider for the system clock
[02:03:02] <rue_2bed> I think the t13 has it
[02:03:05] <Xark> rue_house: Seems most chips come with DIV8 fuse on by default
[02:03:18] <rue_2bed> Icant remmeber if its a fuse or a register bit
[02:03:32] <rue_2bed> ah, maybe thats it, 1mhz vs 8 mhz
[02:03:34] <Xark> rue_2bed: It is a fuse on (e.g.) 328P
[02:03:56] <Xark> Yeah, it makes default RC clock ~1Mhz (vs ~8Mhz)
[02:04:13] <rue_2bed> I thought my interrupt was only going up to 700hz, but it was able to take 15Khz
[02:04:29] <rue_2bed> the motor I was running was the limit
[05:35:11] <Lambda_Aurigae> div8 fuse is on by default making chips run at 1MHz..you can switch the divider in software after bootup to jump to 8MHz or you can unprogram that fuse and have it start at 8MHz.
[05:35:33] <LeoNerd> I've lately taken the idea of setting the clock prescaler explicitly in software
[05:35:43] <LeoNerd> That way, it's built into the program itself rather than relying on the fuses
[05:35:57] <Lambda_Aurigae> LeoNerd, I played with it a while back..fun for changing things around on the fly.
[05:35:58] <LeoNerd> I had a setup where I was /almost/ just wanting default fuses, except for the DIV8 fuse
[05:36:21] <LeoNerd> But all the other fuses were OK at defaults. So then I stopped bothering to remember burning the fuses as well, and suddenly everything runs too slowly
[05:39:36] <Lambda_Aurigae> except for when I'm doing high speed USART comms, the default fuses are usually just fine for what I do...even running at 1MHz.
[06:12:39] <Lambda_Aurigae> Happy Star Wars Day!
[08:13:59] <LeoNerd> Huh.. my Pololu programmer seems to have stopped working :(
[08:14:47] <LeoNerd> The red LED is lit and it doesn't seem to talk to any chip. I just get stk500v2_command(): command failed
[08:16:54] <theBear> what did you do before now ?
[08:17:09] <theBear> and how does it connect to a pc ? does the pc "see" that thing
[08:17:25] <LeoNerd> PC sees the /dev/ttyACM0 and 1 nodes
[08:17:55] <theBear> and is it based on a usb capable avr, or a ft2323 or ?
[08:18:54] <LeoNerd> It's a PIC of somesort I believe.
[08:18:55] <Lambda_Aurigae> pic
[08:18:58] <LeoNerd> The Pololu v1
[08:19:11] <theBear> hmm... usb native ?
[08:19:12] <LeoNerd> hmm.. so according to my scope, it does assert the RESET line for a moment
[08:19:18] * LeoNerd shall probe the other pins
[08:20:19] <Lambda_Aurigae> theBear, yeah, hardware usb on the pic.
[08:20:52] <theBear> hmm interesting
[08:21:11] <theBear> does the programmer id etc before that error look like it working ?
[08:22:54] <LeoNerd> Hmm.. this is interesting. I get a ~RESET pulse but nothing on SCK/MISO/MOSI
[08:23:16] <LeoNerd> Reset pulse probably lasts only 500usec
[08:23:23] <cehteh> chip erase hit the wrong victim :D
[08:23:56] <LeoNerd> Mm?
[08:24:05] <cehteh> jk
[08:24:31] <LeoNerd> I wonder if avrdude knows how to use the FT232H
[08:24:52] <LeoNerd> Hrm.. no. :(
[08:25:05] <LeoNerd> Oooh but it can do buspirate... that might be fun
[08:27:55] <theBear> err, i thought it could in gpio mode
[08:28:12] <theBear> or even bitbang mode maybe, some mode
[08:28:21] <theBear> flashrom can do it one or both ways
[08:28:31] <theBear> but it can't do pic or avr :(
[08:29:00] <LeoNerd> Heh.. and what do youknow... my trusty usbasp works /fine/ on all four of these boards
[08:29:07] <LeoNerd> I think my pololu is broken :(
[08:29:54] <theBear> why would you have a nasty dirty pic based charger anyway ?
[08:30:02] <theBear> this is the avr god's way of punishing you for THAT
[08:32:26] <polishprogrammer> do you know any simple library to use an avr as usb slave?
[08:33:15] <polishprogrammer> i would like to make avr based PC case indicators
[08:34:22] <Lambda_Aurigae> polishprogrammer, which avr?
[08:34:32] <Lambda_Aurigae> one with hardware usb or without?
[08:34:43] <Lambda_Aurigae> and, no there is not a SIMPLE library for usb.
[08:36:06] <polishprogrammer> in my workshop i have Atmega16 and 8 but i think i can get anothers if they are not exotic
[08:37:36] <Lambda_Aurigae> atmega16 and atmega8 can run the v-usb software.
[08:37:45] <Lambda_Aurigae> which is bitbanged low speed usb.
[08:38:06] <polishprogrammer> that seems comfortable
[08:38:15] <Lambda_Aurigae> it's functional but I wouldn't use it for anything critical myself as it makes some assumptions and deviations away from the base usb spec.
[08:38:20] <polishprogrammer> if it fails i\ll just get a cheap uart-usb
[08:38:50] <Lambda_Aurigae> there are AVRs with hardware USB and the software of choice for those is LUFA.
[08:38:52] <cehteh> usually it works, but you need a stable frequency
[08:39:09] <theBear> there's also igor's original pioneering based versions for bitbang usb
[08:39:10] <cehteh> crystal or calibrated internal osc
[08:39:43] <Lambda_Aurigae> cehteh, internal oscillator only works with chips that have the PLL, like the attiny45 and attiny85
[08:39:54] <Lambda_Aurigae> at least, that's been my experience.
[08:40:04] <Lambda_Aurigae> as it relies on that PLL for clock tuning.
[08:40:32] <cehteh> i never used it on others, but the source says it works on others too
[08:40:43] <Lambda_Aurigae> interesting.
[08:40:51] <cehteh> but lower freq then leavng no much room for errors
[08:40:53] <Lambda_Aurigae> they must have updated it since last I played with that feature.
[08:40:59] <cehteh> and you have to change some config settings
[08:41:16] <polishprogrammer> right now (because i'm "beginner/intermediate" with avrs i'm trying to run Atmega16L twice as max frequency because i don't have prope cystals
[08:41:21] <cehteh> i only looked at the source, but using it on tiny85 w/ pll ..
[08:41:25] <Lambda_Aurigae> polishprogrammer, either way, USB is not for the faint of heart.
[08:41:28] <polishprogrammer> the lowest i have is 14Mhz
[08:41:36] <Lambda_Aurigae> twice the max frequency?
[08:41:42] <Lambda_Aurigae> 32MHz?
[08:41:54] <polishprogrammer> 16L version has te max said as *Mhz
[08:41:56] <Lambda_Aurigae> oh..wait...16L is 8MHz max.
[08:41:58] <polishprogrammer> 8Mhz
[08:42:07] <polishprogrammer> i have 14.8313M
[08:42:13] <cehteh> 8mhz might be too low for bitbanged usb
[08:42:15] <Lambda_Aurigae> while you won't damage the chip, it likely won't run stable.
[08:42:25] <cehteh> iirc 12Mhz was the minimum
[08:42:29] <polishprogrammer> that's just an experiment :)
[08:42:36] <polishprogrammer> i'm tinkering around wit avrs
[08:42:37] <cehteh> but read the source
[08:42:40] <Lambda_Aurigae> and v-usb won't run at 14.8313...it has to be 12, 16, or 20
[08:42:54] <cehteh> 16.5
[08:42:55] <polishprogrammer> i'll get the proper crystals on the next shop trip
[08:42:56] <theBear> is that a stardate ?
[08:43:09] <theBear> same shop as the incense ? hehe
[08:43:45] <theBear> you don't put them in the circuit, you just place them nearby, preferably 3 in a isocoles triangle centered on the circuit :)
[08:43:48] <polishprogrammer> right now i\m trying to run an rs485 thermometer
[08:43:54] <Lambda_Aurigae> with usb running on the chip you have to be careful of running your own interrupts or anything realtime that has to run without interrupts at all as the usb comms is very timing critical.
[08:44:15] <theBear> yeah, but in exchange you get usb on the chip :)
[08:44:56] <Lambda_Aurigae> yup.
[08:45:06] <Lambda_Aurigae> which is why I usually use a separate chip for usb connection.
[08:45:21] <polishprogrammer> this seems too advance for me yet
[08:45:40] <polishprogrammer> i'll try usb when i teach myself more
[08:46:01] <cehteh> https://github.com/micronucleus/micronucleus/tree/master/firmware/usbdrv
[08:46:05] <cehteh> see the readme
[08:46:32] <cehteh> https://github.com/obdev/v-usb/tree/master/usbdrv ... original site
[08:47:06] <polishprogrammer> i still do only C, i need to pick up asm
[08:47:16] <cehteh> C is ok .. in most cases
[08:47:43] <polishprogrammer> inb4 bascom basic
[08:47:47] <polishprogrammer> :)
[08:47:55] <cehteh> thats not ok :D
[08:48:16] <Lambda_Aurigae> bascom...how much you pay for that?
[08:48:29] <polishprogrammer> fortunately i dont have it
[08:48:45] <polishprogrammer> i crashed into C with a DAPA cable
[08:49:00] <Lambda_Aurigae> DAPA cable has nothing to do with the programming language.
[08:49:05] <polishprogrammer> i know
[08:49:15] <polishprogrammer> i just said i began with C
[08:50:06] <polishprogrammer> i mentioned the cable because there are people who would buy an STK500 just to find out it's not for them
[08:50:26] <Lambda_Aurigae> I just built an stk200 clone while waiting for my first chips to arrive.
[08:50:41] <theBear> all i needed to see was the price of stk500 to know it wasn't for me
[08:50:41] <Lambda_Aurigae> similar to the DAPA
[08:51:05] <Lambda_Aurigae> I paid $50 for an stk500 and dragon together in a special sale some 10 or 12 years back.
[08:53:01] <polishprogrammer> i use dragon now because i dont have a parport anywhere nea
[08:53:10] <Lambda_Aurigae> lots of parallel ports here.
[08:53:24] <cehteh> i only have $3.50 usbasps
[08:53:24] <Lambda_Aurigae> even on my quad core amd fx board and this laptop.
[08:53:45] <cehteh> mhm and some others .. should check what they are
[08:53:48] <Lambda_Aurigae> the laptop has a portable docking module that has both parallel and serial on it.
[08:54:10] <Lambda_Aurigae> dell docks are good for that.
[08:54:38] <Lambda_Aurigae> am thinking of building some wifi avr programmers from esp8266 modules.
[08:55:23] <polishprogrammer> i have one of teese (esp-12) and i can't get it to work, i'm waiting for a buspirate
[08:55:26] <Lambda_Aurigae> add a battery pack and minimal interface electronics and a-programmin-we-shall-go
[08:55:42] <Lambda_Aurigae> I just got a pair of esp-03 boards and both work fine.
[08:55:55] <polishprogrammer> i will probably make an NTP clock with it
[08:55:57] <twnqx> i randomly sold my second buspirate to someone from this channel last week :)
[08:56:01] <polishprogrammer> to sit on my desk
[08:56:05] <Lambda_Aurigae> was looking at the simple esp-01 modules too and they have everything needed to make a programmer with.
[08:56:15] <polishprogrammer> i found a cheap buspirate made in poland
[08:56:22] <twnqx> polishprogrammer: +1 for this idea, like it
[08:56:26] <Lambda_Aurigae> just make a buspirate.
[08:56:40] <Lambda_Aurigae> it's open source and open hardware.
[08:56:50] <Lambda_Aurigae> same for the logic pirate.
[08:56:58] <twnqx> i dislike the bus pirate
[08:57:12] <twnqx> for the choice of pic, which in fact causes at least one bug, just by its choice
[08:57:12] <polishprogrammer> i could get a green ob
[08:57:16] <polishprogrammer> *green one
[08:57:18] <Lambda_Aurigae> twnqx, it has its uses..not many but I've found a couple.
[08:57:32] <twnqx> i found that the software exceeds the max call depth
[08:57:37] <Lambda_Aurigae> oh?
[08:57:45] <Lambda_Aurigae> I haven't run into that yet.
[08:57:47] <twnqx> yeah, with my spitool for it
[08:58:08] <twnqx> uses binary mode, after some time the pirate just stops doing the expected thing™
[08:58:13] <Lambda_Aurigae> I was able to read and write Xerox CRUM chips with mine.
[08:58:25] <twnqx> and there is no way in the source code to explain its behavior
[08:58:44] <Lambda_Aurigae> still working on the data format but I hope to be able to rewrite them to get more life out of the associated parts.
[08:58:56] <twnqx> yeah, it works
[08:59:03] <twnqx> but not... always... in the right way
[09:00:46] <Lambda_Aurigae> dangit..I want a 1GHz AVR with 512MB sram and 8GB flash in a 40 pin dip package!
[09:00:53] <polishprogrammer> right now my most advanced project is a thermometer that multiplexes 4 7segs
[09:01:34] <theBear> can't adderss 512mb with 8bits
[09:01:40] <cehteh> Lambda_Aurigae: thats called Raspberrry Pi :)
[09:01:44] <cehteh> zero
[09:01:59] <Lambda_Aurigae> but that's an arm
[09:02:02] <Lambda_Aurigae> I want that in an avr
[09:02:12] <cehteh> you can run an arm emulator on it
[09:02:22] <Lambda_Aurigae> I do that already
[09:02:25] <cehteh> haha
[09:02:27] <Lambda_Aurigae> running an arm emulator on an avr.
[09:02:34] <polishprogrammer> well if avr can emulate and run linux it must be possible the other way
[09:02:37] <Lambda_Aurigae> I could, I suppose, run an avr emulator on an arm, but...
[09:04:07] <cehteh> there is this avr emulates arm running linux .. now could we top that to let the emulated linux, emulate a avr again which in turn boots up a arm emulator?
[09:04:34] <Lambda_Aurigae> we could.
[09:04:39] <cehteh> would take appox 10 years to boot, but :D
[09:04:39] <Lambda_Aurigae> but we would die before it boots.
[09:04:45] <cehteh> :)
[09:04:57] <theBear> arm can run a similar spec micro and sound synth chips and crap for things li ke nes emulators, and way faster than they need, surely it can do an avr pretty good
[09:05:12] <polishprogrammer> every time you think about something like this your beard grows a thou longer
[09:05:15] <theBear> cehteh, and i suspect someone kinda did that, at least ac ouple layers, maybe not linux tho
[09:05:18] <theBear> hehe
[09:05:23] <theBear> and further down your neck :(
[09:05:39] <Lambda_Aurigae> theBear, someone did an avr running an arm emulator running linux...I duplicated it here.
[09:05:52] <Lambda_Aurigae> takes hours to boot to a command prompt
[09:05:58] <Lambda_Aurigae> but it does function.
[09:06:01] <cehteh> do you want to die that soon?
[09:06:13] <theBear> sounds about right... and i thought i was breaking ground running gentoo from stage 1 on 40 and 50mhz sparc32's
[09:06:31] <Lambda_Aurigae> this is like, an arm running at several KHz!
[09:06:43] <Lambda_Aurigae> 3 orders of magnitude slower than the sparc32
[09:06:58] <theBear> i can proudly say it took over a week to build gcc AND glibc, and comfortably over
[09:07:11] <Lambda_Aurigae> hehe.
[09:07:12] <theBear> even with raid1'd 4gb scsi drives !
[09:07:27] <Lambda_Aurigae> that would take years on the avr if it even had enough ram to do so.
[09:08:36] <polishprogrammer> is it a good idea to use 74hc595 8bit shift reg to handle 7segment display or is there a better way of doing that?
[09:08:50] <theBear> it's true, that's probably going a little TOO silly, a sentence i never expected to hear come out of my own mouth
[09:09:00] <cehteh> its a simple way, there are others but its ok
[09:09:07] <theBear> polishprogrammer, how many sgements ?
[09:09:10] <Lambda_Aurigae> polishprogrammer, whatever works.
[09:09:16] <theBear> and just led or ?
[09:09:22] <polishprogrammer> 7 segmetns >4 digits
[09:10:15] <theBear> if you ok with matrixing maybe 2 * bcd->7seg logic things, and select lines on another port
[09:10:36] <polishprogrammer> from that thermo i found out that multiplexing 7 segment leds works for not more than 4 digits. More digits just make it dim and i want to avoid bliking
[09:10:56] <theBear> i find in most cases the bcd->7seg things make everything nicer, mostly due to the no-number-lookup/conversion, and in the case of a pair, the 2nd only needs a 4bit shift
[09:11:08] <lorenzo> polishprogrammer: imho the best result is without any multiplexing at all
[09:11:26] <theBear> you know with led ones you can overdrive to varying extents for low duties like that ? but i agree, it's not ideal
[09:11:31] <lorenzo> just use 4 separate 7-segment displays
[09:11:34] <lorenzo> and two cat4016 to drive them
[09:11:35] <cehteh> you can matrix drive it, or charliplex (when you can mix common anode/cathode)
[09:11:36] <cehteh> i think shift registers are the simplest way
[09:11:57] <polishprogrammer> never heard of charliplexing
[09:12:03] <theBear> without multiplex i spose you can do latching buffers, even still use the bcd decoder(s) so save a lookup if you want
[09:12:22] <cehteh> there are shift registers extra for 7seg displays, with drivers, brightness regulation etc
[09:12:29] <theBear> i spose shift regs is good for low pincount, i just try to avoid them in avr land often, to save "time"
[09:12:38] <theBear> seriously ? reasonable prices too ?
[09:12:45] * theBear is fond of his various fig8's
[09:13:38] <polishprogrammer> i just want to avoid lcd's (which i already have handled) because they look ugly for me
[09:13:51] <Emil> twnqx: ?
[09:14:06] <Emil> Are you still at work ; )
[09:16:00] <Lambda_Aurigae> polishprogrammer, harddrive head positioning units and laser diode!
[09:16:07] <Lambda_Aurigae> make a scanning laser display.
[09:16:20] <lorenzo> what's really fun to program with different 7-segment displays is the routine to find the dot in a number
[09:16:23] <theBear> one head unit and one laser printer spinner
[09:16:24] <lorenzo> to display it properly :-)
[09:16:31] <theBear> makes teh flyback instant
[09:16:47] <theBear> and you need all the duty cycle you can get if you only got tiny lasers like me
[09:17:13] <polishprogrammer> i was looking forward to using lasers
[09:17:37] <polishprogrammer> i also looked at flipdots because they require no power if you don't change the content
[09:17:52] <Lambda_Aurigae> hehe
[09:17:54] <theBear> new kind of display you say ? mmmm
[09:18:00] <bss36504> lorenzo: sprintf and a for loop?
[09:18:00] <Lambda_Aurigae> Babbage displays.
[09:18:02] <polishprogrammer> like the tram ones
[09:18:18] <polishprogrammer> split-flap displays too.
[09:18:43] <polishprogrammer> theBear, i can see you like displays too :)
[09:18:45] <theBear> oh, i recently obtained a small one of those to play with... suspect it non-indexed but that can be sorted easy enough
[09:18:55] <theBear> not all displays, but i'm fond of fig8 and flipflops
[09:19:04] <polishprogrammer> fig8 ?
[09:19:06] <lorenzo> bss36504: not if you're using a shitty display driver like ht16k33
https://github.com/lcafaro/avr-drivers/blob/master/ada7seg/libs/ada7seg.c
[09:19:14] <lorenzo> (see void ada7seg_put_text(char *text) {)
[09:19:31] <theBear> 7seg
[09:19:50] <theBear> surely i didn't imagine that i learned that name for them, and i'm the only one ?
[09:19:56] <theBear> i been calling em that since the 80s
[09:19:58] <polishprogrammer> there are electromechanical 7 segs
[09:20:12] <LeoNerd> DOH! My programmer /is/ working fine. It's just not detecting +5V on the Vtg wire, because my current board is 3.3V :)
[09:20:19] <LeoNerd> If I turn it up to 5 it's all fine
[09:20:48] <theBear> woohoo !
[09:21:05] <lorenzo> bss36504: if I ever happen to rewrite that I'll do it in a simpler albeit more expensive way, like strstr to find the position, strip it out of the string
[09:21:06] <LeoNerd> How annoying. My AVR chip itself will cope with 5V but the SD card won't. :/
[09:21:07] <polishprogrammer> theBear,
http://www.flipdots.com/electromagnetic-large-7-segment-display.html
[09:21:15] <lorenzo> and then display the dot *after*
[09:21:22] <LeoNerd> I'll just have to be really careful and switch voltages without SD card in place
[09:21:23] <polishprogrammer> this is a company that makes new flipdots
[09:21:48] <rue_house> hah reliability
[09:22:03] <rue_house> I seen more of those flip displays with stuck pixels...
[09:22:17] <Lambda_Aurigae> polishprogrammer, someone did similar with lego mindstorms a while back...it was on hackaday as I recall.
[09:22:49] <polishprogrammer> i saw that one too but this one uses coils and magnetized planes, making it a sort of magnetic memory
[09:22:53] <theBear> polishprogrammer, oooh ! gonna be hard to inherit one of them tho :(
[09:22:58] <rue_house> one of the great things about those displays is you just have to pulse them, they manitain state
[09:23:21] <polishprogrammer> theBear, i am trying to get them but they are expensive
[09:23:32] <Lambda_Aurigae> rue_house, time to make a fully mechanical one with mechanical shift registers and all?
[09:23:48] <theBear> polishprogrammer, yeah, and i may never be in a position to do expensive again
[09:23:58] <Lambda_Aurigae> make Charlie Babbage proud!
[09:24:00] <rue_house> mechanical binary to 7 seg decoder?
[09:24:02] <polishprogrammer> eventually i will make a [wrist]watch with 1" modules
[09:24:22] <Lambda_Aurigae> wrist watch or forearm watch?
[09:24:29] <theBear> hehe
[09:24:39] <theBear> or four-arm watch, amrate?
[09:24:40] <rue_house> or "its wearable, you just strap yourself in"
[09:24:42] <theBear> ami dammit
[09:25:02] <polishprogrammer> the weight might be a problem
[09:25:11] <Lambda_Aurigae> ok..now I gotta make a leather forearm strap for my phone!
[09:25:30] <Lambda_Aurigae> anything is wearable if you can still walk while having it strapped to your body.
[09:25:31] <rue_house> impracticality has no bearing on a great piece of deisgn work
[09:25:33] <polishprogrammer> but if you are into theese displays just get a bunch of 3V tiny light bulbs and make an eggcrate display
[09:25:46] <rue_house> read the hitchhikers guide to the galaxy
[09:26:06] <Lambda_Aurigae> https://www.sparkfun.com/tutorials/47
[09:26:17] <Lambda_Aurigae> there's your 7-segment clock!
[09:26:24] <Lambda_Aurigae> and nightlight
[09:26:33] <polishprogrammer> i will make a hardcore clock
[09:26:43] <rue_house> thats cheating, its only 12' cause its that long
[09:26:59] <theBear> relevant
https://www.youtube.com/watch?v=IetE4U3EI-c
[09:26:59] <Lambda_Aurigae> rue_house, and it's all open source!
[09:27:15] <rue_house> http://ruemohr.org/~ircjunk/projects/wallclock/p1070558.jpg
[09:27:17] <theBear> at the end of the episode they show the solution to the heaviness too, but there are some shortfalls
[09:27:35] <rue_house> I cant call mine a 24" clock can I?
[09:28:10] <theBear> it's a time clock, silly
[09:28:15] <Lambda_Aurigae> sure.
[09:28:35] * cehteh wants a laser projection clock on the ceiling .. but i havent found anythin suitable yet
[09:28:50] <cehteh> there are this 'projector clocks' but most of them suck
[09:29:08] * WormFood wants a girl who can suck his balls while he fuck her.
[09:29:11] <cehteh> doesnt need to be bright, but stable over years, focused and big
[09:29:22] <polishprogrammer> i want to go to the tram department of my city and get an old flipdot from a tram and make it a desk clock
[09:29:32] <rue_house> WormFood, dude, your off topic, the topic is clocks damnit, CLOCKS
[09:29:49] <theBear> china makes nice cheap laser-scanner multi colour illegal-power things for cheap, none i seen that know how to clock alraeady tho... some with external control inputs tho
[09:30:11] <polishprogrammer> i would like to keep my wision stereo and full color
[09:30:12] <rue_house> "cuts the time into your cieling"
[09:30:34] <cehteh> sleeping room, should be dark
[09:30:39] <WormFood> I like the persistance of vision clocks.
[09:30:49] <cehteh> but big enouh to be readable w/o glasses
[09:30:50] <rue_house> ^^ that wall clock I made it REALLY bright
[09:31:15] <rue_house> 25x 3w leds
[09:31:19] <WormFood> a BCD clock would be trivial to read, but would fuck up anyone who doesn't understand binary
[09:31:26] <rue_house> running really, really lightly
[09:31:42] <rue_house> WormFood, there are 10 types of people you know...
[09:31:45] <WormFood> There are 10 types of people in this world. Those that understand binary, and those who don't. ;)
[09:32:09] <polishprogrammer> but yeah, back to flipdots
[09:32:29] <rue_house> http://ruemohr.org/~ircjunk/projects/wallclock/p1070500.jpg
[09:32:31] <Lambda_Aurigae> flipdots....you need Vannah White to flip them for you.
[09:32:44] <rue_house> what about 3w leds and custom cut foam masks?!?
[09:32:49] <polishprogrammer> i need a comonent that can switch to give out a fair amunt of -5 and -5 volts
[09:33:09] <Lambda_Aurigae> relay, mosfet,
[09:33:10] <rue_house> heh
[09:33:14] <polishprogrammer> in order to flip the dots because their control boards are expenive so i'll amek one myself
[09:33:15] <WormFood> oh, you want -5 volts, AND -5 volts. I see
[09:33:22] <rue_house> you just need to pulse them
[09:33:22] <polishprogrammer> -5 and +5
[09:33:35] <rue_house> polishprogrammer, AOP605
[09:33:40] <cehteh> rue_house: whats the point in having the time burned into your retina?
[09:33:59] <rue_house> I dialed the current down really far on the leds
[09:35:11] <rue_house> it still lights up a room tho
[09:35:25] <cehteh> sounds a bit useless :D
[09:35:32] <rue_house> na
[09:35:35] <cehteh> well for lights
[09:35:37] <rue_house> I keep it in the livingroom
[09:35:46] <Lambda_Aurigae> time to make,,,ceiling fan POV clock!
[09:35:47] <rue_house> it was going to be a bedroom clock
[09:36:04] <polishprogrammer> the idea is there's a power source switchable from -5 to 5 volts and a way to select the pixel. then the current in the needed direction is let through the col to make it the right state
[09:36:10] <cehteh> we have a huge LCD clock here in the office thats neat
[09:36:22] <rue_house> polishprogrammer, AOP605
[09:36:38] <polishprogrammer> i'm looking at the datasheet now rue_house
[09:36:43] <Lambda_Aurigae> polishprogrammer, I thought those things just did a pulse to change the pixel...rather than different voltage to switch it back and forth.
[09:36:52] <rue_house> if you were looking on digikey you would have already found it
[09:37:15] <polishprogrammer> they need a pulse of either + or _ to magnetise the disk that then stays held by the magnetic forces
[09:37:20] <polishprogrammer> + or -
[09:37:40] <WormFood> right, because a pulse of 0 does nothing.
[09:38:09] <Lambda_Aurigae> different tech than the ones I've seen then.
[09:38:11] <rue_house> iirc mine have three terminals
[09:38:13] <Lambda_Aurigae> sounds more complicated.
[09:38:20] <rue_house> common, and one for each dir
[09:38:33] <polishprogrammer> 3 terminals are probably easier
[09:38:38] <polishprogrammer> my has 2 terinals
[09:39:38] <rue_house> has anyone made a 3d printable flip segment?
[09:39:51] <polishprogrammer> haven't sen
[09:39:53] <polishprogrammer> seen
[09:40:29] <rue_house> AAAAAAAA thingverse has a whole freaking section of marble machines
[09:42:21] <rue_house> why nto make a marble clock
[09:45:13] <rue_house> http://www.thingiverse.com/thing:371248
[09:45:16] <rue_house> what about just that
[09:47:20] <rue_house> nope, no flipflop stuff on thingverse
[09:48:20] <polishprogrammer> but for now i either buy a complete module with controller or make an eggcrate display
[09:48:29] <polishprogrammer> with mosfets
[10:30:33] <LeoNerd> So.. heh.. Turns out the v1 of the Pololu AVR programmer doesn't really do 3.3V devices anyway, only 5V
[10:30:34] <LeoNerd> :/
[10:31:07] <theBear> err, obviously ?
[10:31:19] <theBear> or, err, obviously.
[10:31:28] <LeoNerd> That's not at all obvious
[10:31:35] <LeoNerd> The v2 works fine for 3.3V as well as 5
[10:32:21] <theBear> only a few lines isn't it ? might even get away with just the reset, make one of those little fet buffers, ifi t just reset even a single transistor buffer might do it, or a buffer+diode clamp, not sure if it gotta go both ways
[10:32:37] <LeoNerd> Oh, I have a level shifter
[10:32:40] <theBear> i figured teh whole not-seeing-reset/not working at all woulda been an obvious
[10:32:42] <theBear> hooray
[10:32:46] <LeoNerd> It'll just be awkward to put that inbetween
[10:32:53] <LeoNerd> I might just ignore it for now and use the usbasp for this
[10:43:54] <polishprogrammer> for my next build i will need a good voltage reference equal to 0,7746 or 0,8691 volts
[10:44:15] <polishprogrammer> what voltage referenes are easily available ?
[10:44:31] <LeoNerd> Those sound rather odd values. Easiest would be to take something more standard and divide it.. or fix in software
[10:44:47] <LeoNerd> 1.0, 1.25, 1.5 are probably easy
[10:45:27] <polishprogrammer> i'll check the standard. Do you think a resistor divider is suitable to connect to aref?
[10:45:44] <polishprogrammer> i'l check aref's current drain
[10:46:00] <eszett> !hi!
[10:46:27] <eszett> question, do you think the solder in the HASL coat would be sufficient to tack a SMD part (IC) down, when hot air is applied?
[10:48:12] <LeoNerd> Depends how accurate you want it. You quoted 4 significant figures there - that's .01%
[10:48:15] <LeoNerd> Do you /really/ need that?
[10:48:34] <LeoNerd> eszett: They're usually really thin
[10:48:51] <polishprogrammer> well, i'm making a digital peak/vu meter
[10:49:06] <polishprogrammer> so let's say 2 figurerr
[10:49:11] <polishprogrammer> *fugures
[10:49:15] <polishprogrammer> fiures
[10:49:18] <polishprogrammer> figures
[10:49:22] <polishprogrammer> my keyboard sucks
[10:49:40] <LeoNerd> Well that's somewhat easier. I'd just take a 1.0V ref and divide it. or similar
[10:50:23] <eszett> Leonerd: well, either the IC is firm in place by just HASL solder, or not, there is no inbetween?
[10:50:31] <eszett> +hot air of course
[10:50:42] <eszett> Ever tried it out?
[10:51:34] <polishprogrammer> LeoNerd, i think hat's then the easiest solution
[10:51:34] <LeoNerd> No.. I hardly ever get HASL boards anyway. I usually use OSHpark who are ENIG
[10:51:50] <LeoNerd> Except the one time I used Ragworm, but that board is mostly DIP TTH parts so I add plenty more solder anyway
[10:52:26] <polishprogrammer> i thought that because 0,77etc. is +0DBu somebody could make a reference just for the sake of audio meters.
[10:52:46] <LeoNerd> I doubt it
[10:53:20] <theBear> in audio it's 0.775 in hifi and some pro land, but it's never followed accurately
[10:53:28] <theBear> err, p-p i think, been a while
[10:53:49] <polishprogrammer> 0,775 seems like i could make it with a voltage divider
[10:54:09] <polishprogrammer> i just need to get some accurate resistors or a trimmer
[10:54:26] <polishprogrammer> a simple trimmer will do, it's not rocket science
[10:55:08] <theBear> wait, what is this, not audio related ? either way i don't know any common .775v ref's, don't think any exist
[10:55:17] <theBear> remember temp will effect a trimmer
[10:55:52] <polishprogrammer> yes yes, i know
[10:56:01] <theBear> just reminding yer :)
[10:56:24] <polishprogrammer> it's very audio related
[10:59:54] <theBear> yeah, but being a retired audio tech and repairer and designer, i can confidently say it's not commonly used or needed
[11:00:06] <theBear> what you doing with it ?
[11:03:29] <LeoNerd> https://www.tindie.com/products/madworm/avr-isp-level-shifter/ <== boo. Retired. I see a gap in the market.. :)
[11:03:53] <LeoNerd> 'cept I'm probably going to make mine on an ADuM1401, so it's *isolated* and shifted
[11:05:18] <theBear> they around, lots of shield-maker kinda companies have em, they just don't put the isp bit in the name
[11:05:31] <LeoNerd> Mmm?
[11:07:06] <theBear> http://www.jaycar.com.au/Kits%2C-Science-%26-Learning/Science-Lab-Equipment/Instruments/TTL-Level-Shifter-Shield-for-Arduino/p/XC4599 like taht
[11:07:25] <LeoNerd> Yesyes.. but that's just a generic level shifter
[11:07:29] <theBear> when i was rushing something couple months ago they had a different brand 4 way one
[11:07:32] <LeoNerd> I very specifically want one with the ISP 2x3 connector on it
[11:07:40] <LeoNerd> Something tiny I can stick inline on that connector and have it JustWork
[11:07:53] <theBear> isn't the one you linked just, oh, you think that's a market gap tho ? in this age of tarduino maybe it is, sigh
[11:08:25] <LeoNerd> I would like to buy a little board with a 2x3 pin header on one side and a 2x3 socket on the other, that does level shifting and maaaybe isolation
[11:08:51] <polishprogrammer> theBear, i will make a stereo peak meter and place it on my stereo
[11:08:53] <LeoNerd> I'm aware I can buy all manner of boards that have some number of shifter channels in them. I don't see any specifically around that have the ISP6 header layout on the connector
[11:08:55] <Lambda_Aurigae> maybe we should make up our own ardweeny killer...call it non-duino.
[11:09:06] <Lambda_Aurigae> use arduino hardware as it's all out there everywhere.
[11:09:12] <polishprogrammer> which acts as a pair of speakers for the pc
[11:09:16] <LeoNerd> Also I don't believe I mentioned Arduino anywhere
[11:09:26] <Lambda_Aurigae> but do a decent simple C built environment with some libs.
[11:09:43] <Lambda_Aurigae> nono...totally off the current subject...just a thought I had.
[11:11:09] <polishprogrammer> Lambda_Aurigae, you could try to get a normal 5v-3v3 shifter and mount the headres on it or mount it on a veroboard with theaders wired
[11:14:05] <theBear> polishprogrammer, so err, how you need a voltage ref for that ?
[11:15:07] <polishprogrammer> the voltage ref is conected to avr's aref, so say the ref is 0,77 then a full reading (1024) from adc means our signal has 0dBu
[11:15:29] <theBear> and if it in something that also has a power amp, it makes much more sense to measure a scale of 0-100% against taht, which is generally/always still just a maybe hand-trimmed or just close fixed resistor non-referenced kinda thing (and also depends on load impedance, which is why on a stereo you probly shouldn't trust it too much
[11:15:31] <LeoNerd> Yah I wouldn't do it that way
[11:16:28] <theBear> outside of pure digital land metering, every album and tv program/ad and movie you ever heard didn't do it against a ref
[11:16:55] <theBear> also you can get cheap single chips that do it really well like the lm err, 1085 ? no, some number like that
[11:17:09] <polishprogrammer> so the program takes the reading, calculates the actual voltage basing on the formulas in the datasheet, then put the voltage into the `20 log (voltage/reference)` which is the formula to work out the decibel value and basing the value it lights proper leds connected to one of the ports, theBear
[11:17:32] <LeoNerd> But you don't need to pick an exact reference voltage of your weir d0.7mumble for that
[11:17:34] <polishprogrammer> sorry for typos
[11:17:35] <LeoNerd> Just use the internal 1.1V
[11:17:39] <theBear> also it's non-trivial to measure both halves of the wave, and my sketti is cooked in 30 seconds, therefore *poof* goneski
[11:17:40] <LeoNerd> You can perform a multiplcaition/division
[11:17:48] <LeoNerd> It's what *literally* everyone else does
[11:18:57] <polishprogrammer> the internal reference is so off that when i took the reference instead of the vcc on my thermometer it shown me 50deg c which is way too hot. I put 1,23V like i found in the datasheet but if the reference is ok but 1.1 volts then it means i made a mistake
[11:19:01] <LeoNerd> So then you can plug that new value into your log20 formulate and work out how many LEDs to display
[11:19:08] <polishprogrammer> yes
[11:19:08] <LeoNerd> Except yaknow, I'd personally do it totally backwards from that
[11:19:21] <LeoNerd> I'd work out in advance what raw ADC sense values correspond to how many LEDs to light up
[11:19:22] <polishprogrammer> ?
[11:19:31] <LeoNerd> Then i'd read the ADC and compare it to my lookup table, and then I'd know how many LEDs
[11:19:33] <polishprogrammer> it will probably be done
[11:19:39] <LeoNerd> No complex maths goes anywhere near the AVR then
[11:19:40] <polishprogrammer> that is faster
[11:20:28] <polishprogrammer> i have eight leds for +1, 0, -3, -6, -12, -18, -24 and -inf db
[11:20:39] <LeoNerd> Sure. So that's pretty easy
[11:20:45] <polishprogrammer> so i'll probably make a progmem array where i store the values
[11:20:54] <LeoNerd> For each LED, work out the minimum ADC read value you'd have to observe, to cause that LED to light up
[11:21:11] <polishprogrammer> because i have +1 i will need a reference bigger than 0,7 so internal reference might help
[11:21:17] <polishprogrammer> if it's accurate
[11:21:32] <LeoNerd> It'll be accurate enough to decide a choice between 8 LEDs
[11:21:50] <polishprogrammer> yeah, the avr would be better with no complex maths
[11:22:44] <polishprogrammer> right now i will try to use internal reference
[11:31:11] <polishprogrammer> bye
[11:32:41] <Lambda_Aurigae> you can do complex math on an avr.
[11:32:45] <Lambda_Aurigae> just not fast
[11:34:16] <LeoNerd> You /can/ but IMHO you'd be ill-advised to
[11:34:37] <Lambda_Aurigae> floating point libraries are rather large too.
[11:34:40] <Lambda_Aurigae> and, again, slow.
[11:34:43] <Lambda_Aurigae> but they work.
[11:34:54] <Lambda_Aurigae> if you aren't doing anything time critical or that needs to be done real fast..
[11:36:32] <mohsen__> Will the motor get hurt in case the object connected to it be heavy?
[11:36:53] <mohsen__> Heavy enough to lower the motor's speed.
[11:41:26] <mohsen__> I mean a motor that turns an object.
[11:42:55] <mohsen_1> Will the motor get hurt in case the object connected to it be heavy?
[11:43:00] <mohsen_1> Heavy enough to lower the motor's speed.
[11:43:04] <mohsen_1> I mean a motor that turns an object.
[11:54:59] <mohsen_1> Hello?
[11:56:02] <LeoNerd> Who knows
[11:56:06] <LeoNerd> It dpends on the motor.. the use-case
[11:56:18] <LeoNerd> The power supply. The actual torque as compared the motor's maximum ratings
[11:56:26] <LeoNerd> Lots of things. We don't know the answers. Also this is #avr, not #motors
[11:58:53] <theBear> most motors designed for some load, which implies speed lowering, with most motor types at least
[11:59:02] <mohsen_1> I see.
[11:59:14] <theBear> loaded current vs free-running is probly a good hint
[11:59:22] <LeoNerd> Also synchronous vs. asynchronous motors will behave differently
[11:59:25] <theBear> the motor should have some kinda power/torque rating too
[11:59:28] <LeoNerd> Vs DC ones
[11:59:31] <LeoNerd> Vs. steppers/servos
[11:59:37] <theBear> or bldc
[11:59:55] <LeoNerd> Basically you could write us a thousand words of description on your problem and we'd *still* have very little information to go on, let alone the tiny scrap we have already
[12:00:04] <theBear> yup
[12:00:23] <theBear> plus its time for me to wash me
[12:01:55] <mohsen_1> What about stopping it?
[12:02:07] <mohsen_1> Is it also unpredictable?
[12:02:08] <theBear> the shower ? i just use the tap
[12:02:13] <theBear> works every time so far
[12:02:22] <mohsen_1> I mean the motor:P
[12:02:44] <LeoNerd> eszett: Was it you I was talking to about the Pololu AVR programmers
[12:03:16] <eszett> LeoNerd hmm i think you are confusing me with someone else..
[12:03:21] <LeoNerd> Hrm..OK
[12:03:22] <mohsen_1> I mean stopping the motor from rotating using an external force.
[15:58:32] <LeoNerd> I shouldn't listen to Radio 4 comedy while soldering 0603s... I laughed so much and now I don't know where this one went
[17:25:33] <phinxy> My 1284p with decoupling caps, inductive high-pass filter and a 6000uF backup cap is still getting reboots when i power a HID lightbulb near it.
[17:25:51] <phinxy> it ought to be some magnetic stuff flying in to the chip and making it panic
[17:26:45] <phinxy> maybe i should build a Faraday cage for it.....
[17:27:05] <Lambda_Aurigae> without some kind of schematic, no way to know what's going on.
[17:27:10] <Lambda_Aurigae> and what is a HID lightbulb?
[17:27:30] <phinxy> The thing is the bulb is not connected to the circuit
[17:28:11] <phinxy> well, it is.. but its behind a regulator and it should not interfere trough the cables
[17:28:28] <phinxy> It's a car headlight
[17:28:35] <Lambda_Aurigae> oh.
[17:28:46] <Lambda_Aurigae> to me HID is a human interface device...like a keyboard or mouse.
[17:28:53] <Lambda_Aurigae> being something usb.
[17:28:54] <phinxy> Yeah
[17:34:10] <cehteh> limit the startup power of the lightbulb somehow
[17:35:10] <cehteh> softstart is better for the bulb as well
[17:46:37] <cehteh> phinxy: inductive high pas filter? .. shouldnt that be a low pass?
[17:58:04] <phinxy> it removes high frequency noise
[18:00:14] <cehteh> a low pass would
[18:00:39] <Lambda_Aurigae> high pass passes high frequency, blocks low
[18:00:49] <Lambda_Aurigae> low pass passes low and blocks high.
[18:02:03] <eszett> this is just a great idea, im thinking about ordered some blu tack stuff
https://www.youtube.com/watch?v=pdGSFc7VjBE#t=7m3s
[18:03:01] <Lambda_Aurigae> bees wax or parafin works as well.
[18:03:05] <eszett> he recommends tacky plasticine as cheap vacuum tweezer replacement
[18:03:09] <eszett> hmm yes_
[18:03:15] <cehteh> i am using some goo for such tihngs
[18:03:22] <Lambda_Aurigae> I've used wax to hold screws to screwdrivers for many years.
[18:03:47] <eszett> cehteh: with goo you are referring the stuff in a children toy store?
[18:03:48] <Lambda_Aurigae> I keep a ball of beeswax in my toolkit for just such
[18:04:09] <cehteh> eszett: actually 'plastic fermit' .. some putty
[18:04:19] <eszett> ahh ..
[18:04:49] <Lambda_Aurigae> also plumbers putty works well.
[18:05:26] <cehteh> plastic fermit is plumbers putty
[18:05:44] <Lambda_Aurigae> ok.
[18:05:48] <Lambda_Aurigae> never heard of it called that.
[18:05:55] <Lambda_Aurigae> any sticky putty works though.
[18:05:58] <cehteh> german brand
[18:06:11] <Lambda_Aurigae> I get my bees wax from these little cheeses I eat.
[18:06:16] <cehteh> http://www.fermit.de/index.php?lg=de&id=3&prod=13
[18:07:52] <Lambda_Aurigae> eszett, his little "tip" is nothing new...it's been done and redone for many years.
[18:08:24] <phinxy> mikeselectricstuff latest video is awesome, he is the smartest person i know on the internet.
[18:08:36] <phinxy> applied science is also quite smert
[18:08:43] <Lambda_Aurigae> things like this get lost because we don't do apprenticeship anymore.
[18:08:51] <Lambda_Aurigae> I learned it from my grandfather.
[18:09:02] <eszett> Lambda: yes but new for me, sometimes those "poor man's tools" are even better than expensive tools advertised everywhere
[18:09:40] <eszett> phinxy: yea and at the same time he is pretty understatement-modest, as if everythings was just kindergarden...
[18:12:34] <phinxy> humble (?)
[18:12:44] <eszett> hehe, im not english native
[18:13:33] <eszett> even more usefull would be to use such a tacky mass to tack components down before hot air soldering, so that they arent blown away
[18:14:18] <Lambda_Aurigae> again, a bit of wax.
[18:14:45] <eszett> i have wax here its not tacky enough
[18:14:56] <cehteh> beeswax
[18:15:16] <eszett> hmm, maybe
[18:15:30] <cehteh> mhm melting beeswax with colophonium should make it more sticky too
[18:16:01] <cehteh> normal paraffine isnt much sticky
[18:16:15] <cehteh> parafine-wax
[20:13:28] <inflex> meh, just spend $10 and get a vacuum pencil setup
[20:14:04] <inflex> aquarium pump, hose, t-piece, 5c needle and a bit of hotglue and drilling
[20:14:08] <inflex> saves a lot of drama
[20:14:35] <Lambda_Aurigae> bees wax on the screwdriver works even without power.
[20:16:27] <Valen> sticky is bad
[20:16:40] <Valen> letting go of the damn thing is just as important as picking it up
[20:16:54] <Lambda_Aurigae> hold it down and solder a couple of pins then it pulls right off.
[20:20:27] <inflex> yeah, not so easy with 0603 or similar size :)
[20:20:35] <Lambda_Aurigae> true
[20:20:53] <Lambda_Aurigae> works for tqfp chips and soic
[20:21:25] <Lambda_Aurigae> and it's an old trick to use on screwdrivers where you don't want it magnetized.
[20:38:15] <Valen> solder paste + frying pan is our system
[20:38:24] <Valen> we use a fridge pump
[20:47:46] <eszett> someone ever used "temperature indicating crayon"_? (
http://store.curiousinventor.com/guides/Surface_Mount_Soldering/Tools )
[20:47:57] <eszett> is it any worth?
[20:49:21] <inflex> Valen, wondering these days if a pan/skillet isn't a more reliable option than my reflow oven (cold spots etc)
[20:50:02] <Valen> we actually use a 3mm Al plate over a gas burner on the stove ;->
[20:50:54] <eszett> i hope you use lead free solder?
[20:51:24] <Lambda_Aurigae> what's a little lead between friends?
[20:51:25] <eszett> even HASL has lead, isnt that a problem in kitchen with food an dstuff?
[20:52:45] <Valen> don't eat the solder?
[20:53:00] <Valen> lead is pretty non volatile
[20:53:10] <Lambda_Aurigae> now you tell me.
[20:53:21] <Lambda_Aurigae> I suppose I shouldn't be playing with the mercury too.
[20:53:31] <Valen> eh its pretty fine really
[20:53:44] <Valen> its organic mercury compounds that cause the problem
[20:53:46] <Lambda_Aurigae> not like I plan on fathering any children or anything.
[20:54:04] <Valen> put it this way they used to feed it to people with constipation
[20:54:30] <Lambda_Aurigae> they used to have x-ray machines in shoe stores too.
[20:55:30] <Valen> if you don't understand the difference between organic mercury compounds and elemental mercury you are going to have a bad time at chemistry, but at least it'll be brief
[20:55:39] <Lambda_Aurigae> hehe.
[20:55:54] <Lambda_Aurigae> I have a pound of medical grade mercury here.
[20:56:03] <Lambda_Aurigae> haven't found a use for it yet.
[20:56:07] <Valen> "medical grade mercury"
[20:56:13] <Valen> what do they use it for these days?
[20:56:21] <Lambda_Aurigae> bought it at an auction when a dental office went out of business.
[20:56:26] <Lambda_Aurigae> mercury silver amalgam.
[20:56:27] <Valen> ahh that
[20:59:51] <inflex> Or trying to make adamantium
[21:00:09] <Lambda_Aurigae> well, I kinda thought about making fulminate of mercury for the fun of it.
[21:00:17] <Lambda_Aurigae> but I need a secure place to do so.
[21:00:24] <Lambda_Aurigae> won't do it in the basement.
[21:00:24] <aandrew> you have a weird definition of fun
[21:00:29] <Lambda_Aurigae> I value my house too much.
[21:00:34] <Lambda_Aurigae> explosives are always fun.
[21:00:46] <aandrew> true enough
[21:00:50] <Lambda_Aurigae> I've made nitroglycerine before.
[21:00:52] <inflex> Until you're in the blast radius
[21:00:54] <Lambda_Aurigae> that was lots of fun.
[21:01:04] <aandrew> I used to have a giant pickle jar full of gunpowder from taking apart hundreds of firecrackers
[21:01:24] <aandrew> looking back I had no idea how unbelievably dangerous that was
[21:01:35] <Lambda_Aurigae> firecrackers....take apart shotgun shells and get some good smokeless powder.
[21:01:47] <aandrew> the air was full of dust and if we turned on a lamp or the heater turned on or off that could have been very, very bad
[21:02:02] <aandrew> not to mention what could have happened if the jar went off
[21:02:14] <aandrew> I'm talking probably 2 gallons of the stuff
[21:02:19] <Lambda_Aurigae> fun fun.
[21:02:36] <Lambda_Aurigae> I have about a quart of gelignite out in the shed.
[21:03:04] <Lambda_Aurigae> found it when we were cleaning out the father-n-law's barn when he sold his property about 4 years ago.
[21:10:06] <aandrew> never heard of that stuff
[21:10:28] <Lambda_Aurigae> https://en.wikipedia.org/wiki/Gelignite
[21:11:11] <Lambda_Aurigae> it's a relatively stable nitrocellulose and nitroglycerine mixture suspended in wood pulp.
[21:11:55] <Lambda_Aurigae> farmers used it around here to blow rocks nd stumps.
[21:12:15] <Lambda_Aurigae> this stuff is old but from what I can find out it remains stable so long as it's in a sealed package.
[21:12:33] <Lambda_Aurigae> and requires a detonator to set it off..
[21:12:49] <Lambda_Aurigae> you can burn it in a camp fire and not detonate it.
[21:25:56] <inflex> will be scary the day we have antimatter bombs :(
