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[00:01:46] <carabia> and yeah, should've been PB2. I need my morning coffee.
[00:03:00] <chendry> hehe :) Where are you such that it's morning?
[00:03:33] <carabia> finland. and no it's not nice.
[00:04:41] <chendry> brrrr. well, thank you much for the help, and happy Monday from Sunday!
[00:04:58] <carabia> i have a nice and easy morning as i was at the office on saturday to finish a project... I don't have to leave for another hour but i don't like the prospect of having to step outside at all
[00:06:23] <chendry> yup, I have about 4 weeks (optimistically) before my nuts freeze off here in Chicago.
[00:09:32] <chendry> do you work with micros and such professionally?
[00:09:35] <carabia> yeah, first snow was laid down super early this year. Can't even remember tha last time we had it in november. Then again long-term memory isn't my forte
[00:09:56] <carabia> yeah
[00:10:59] <chendry> oh, cool! I keep thinking that would be a fun route to go. Clearly lots of learning ahead of me though
[00:11:30] <carabia> perhaps but the indians take over everything!!
[00:11:50] * carabia hides
[00:11:54] <chendry> ha, yeah, happens in my world too :) (I'm more of a software guy)
[00:12:47] <_ami_> carabia: :)
[00:13:41] <carabia> chendry: especially there!
[00:13:50] <chendry> where?
[00:13:55] <carabia> in software
[00:14:53] <chendry> oh yeah :) i've seen it work to varying degrees of success. We did something once where we had a team in India, but we'd exchange a couple people once every couple of months or so, and that was just about perfect
[00:17:53] <chendry> well, what advice for somebody who's decent on the programming side but otherwise a total idiot for getting in to this hardware-y stuff?
[00:18:55] <carabia> well i have a few guidelines and suggestions
[00:19:04] <chendry> sweet!
[00:19:18] <carabia> step 1: don't watch eevblog, step 2: ??? step 3: profit
[00:19:31] <chendry> ha! i love eevblog! why step 1?
[00:19:37] <_ami_> chendry: i am awesome in software ;) but knows a little bit of hardware. learned a lot by googling and asking questions here! :)
[00:20:12] <_ami_> carabia is a very helpful and others here too.
[00:20:14] <chendry> _ami_: cool! yeah, man, i'm still trying to wrap my head around a lot of it. What's your software background?
[00:20:28] <carabia> chendry: "i got this sweet scope did i already mention it costs 50k?"
[00:20:51] <carabia> "i got this sweet multimeter did i already mention it costs $2k, but it's rugged!!"
[00:21:04] <carabia> cause yes, he's known for his harsh working environments
[00:21:04] <chendry> pretty-much eevblog and mjlorton have been my routine as my kid naps on me
[00:21:37] <carabia> I think if you want an entry-level approach to electronics in general you are probably well off by getting that forest mimms book
[00:21:49] <carabia> I haven't read it myself but I have heard good things about it
[00:22:30] <carabia> I'm not quite sure as to how kiddy the book is. You might want to look into other books too
[00:22:43] <chendry> carabia :) yeah, lots of multimeter reviews... but just for somebody who is an idiot like me, just watching him explain a logic analyzer for 20 minutes is so helpful. Not that I'm about to go out and get one, but learning the pros and cons just helps
[00:23:28] <chendry> carabia: yes! I actually got that one, I think. It's hand-written, yeah?
[00:23:31] <carabia> After reading an entry-level book, get the art of electronics, with hopefully updated digital section on the new edition
[00:23:44] <carabia> chendry: I think it's styled like so... I don't know, I don't have it
[00:24:31] <chendry> carabia: The Art of Electronics... I've heard that's a great book. "The Art of Computer Programming" was my introduction to the software world, so I have a soft spot in my heart for the title at least :)
[00:24:33] <carabia> read art of electronics through once, taking your time, and afterwards it's an amazing book to have as reference.
[00:25:12] <chendry> carabia: is it like a really terse, slow-going, information-dense read?
[00:25:15] <carabia> but it's not a book for a complete novice, you want to have some background knowledge of the basic concepts
[00:25:23] <carabia> art of electronics?
[00:25:31] <chendry> carabia: yeah, art of electronics
[00:25:44] <carabia> the question isn't really slow-vs-fast going
[00:25:52] <carabia> it's more of a reference-type book, really
[00:26:31] <_ami_> carabia: suggestion for animating a text on ST7735?
[00:26:31] <_ami_> i am thinking "show text" -> start a timer -> in timer callback, "blank the text area by filling a background color rectangle", probably two timer callbacks are needed.
[00:27:17] <carabia> well yeah for animating you need some sort of a delta-t
[00:27:17] <_ami_> carabia: not sure if anyone can finish art of electronics in his/her lifetime. its just too FAT :P although i have it and its an incredible book.
[00:27:48] <carabia> _ami_: well, a lot of the digital stuff in the older revisions are merely curiosities now
[00:28:25] <carabia> hopefully the new edition stripped them off with more up-to-date stuff, i hope they some arm-coverage
[00:28:35] <carabia> they have, even
[00:28:58] <_ami_> i have 2015 rev and i think its the latest one. are they any new rev coming soon?
[00:29:04] <_ami_> there*
[00:29:14] <carabia> the third edition, i don't know when it was released...
[00:29:45] <carabia> _ami_: anyway your text animation begs the question, how big of a text we're talking here?
[00:30:05] <carabia> doing rgb565/666 over spi is by no means fast and you might end up with blinky business
[00:30:21] <_ami_> its not that big: "player 1"
[00:30:39] <carabia> yeah but the question is how big are the letters
[00:32:58] <_ami_> pixels size of characters you meant?
[00:33:01] <carabia> yes
[00:33:58] <carabia> if you have enough ram to spare you could store the partial buffer in memory and just transfer the bitmap over to overwrite the area after the timer callback fires
[00:34:17] <carabia> skipping any intermediate rectangle fills in between
[00:34:23] <_ami_> aha, thats a good idea!
[00:35:02] <carabia> though, as it's an avr... ram is scarce and your animation might be moving around a lot...
[00:36:49] <carabia> you could save memory to compress the color data to 8 bits per pixel or even a single bit for black/white but then there's the overhead of decoding it on the fly to feed the screen... there are endless possibilities!
[00:37:05] <carabia> to compress... err i mean *by compressing*
[00:37:30] <_ami_> thanks for the pointers. i gonna try and check which is best. a lot to learn.
[00:38:31] <carabia> yeah, those are your options i guess. Well one more is do to per-pixel translation but that starts to get heavy computationally
[00:39:01] <carabia> yeah no biggie
[00:40:27] <_ami_> btw,
https://github.com/amitesh-singh/amiduino/blob/master/avr/workspace/ST7735/ST7735.cpp - i finished this last night. although code is not too tight.
[00:41:17] <_ami_> its loosely based on adafruit lib for st7735
[00:42:54] <carabia> the init sequence seems similar to that of the ili9341
[00:43:53] <carabia> that's a great display, iirc the init sequence had some magic commands pulled out of thin air that were undocumented but included in the datasheet's example init code
[00:44:03] <carabia> ...
[00:45:23] <carabia> I wonder how expensive are screens with enough internal memory to facilitate a double buffer
[00:51:53] <carabia> but it would be a very niche type of thing. anyway, gotta run, laters!
[01:10:07] <ferdna> what bluetooth stack will you go with and why? texas instruments stack or blueradios?
[01:46:05] <Qwertie> The ATmega328P can be used on its own right?
[01:54:11] <sabor> Qwertie: the minimum to get it running is a power source, and the recommended block capacitor
[11:48:21] <Jartza> EHLO
[12:08:09] <carabia> ACK
[12:26:25] <Tom_L> NAK
[12:26:36] <learath> XMASTREE!
[12:26:42] <learath> (now you crash)
[12:35:58] <twnqx> stop setting excessive bits
[13:03:00] <carabia> shit, now i'm frozen
[13:03:24] <carabia> and i'm shitting all over your bus so have fun
[13:04:36] <eszett> hi
[13:04:52] <eszett> an Atmega8 can deliver max. 40mA per GPIO right?
[13:05:08] <cehteh> but not all at the same time
[13:05:32] <cehteh> there is some package power limit, forgotten how much 200mA or less
[13:05:33] <eszett> hi cehteh, im considering driving a matrix of LED with the atmega32u2
[13:05:41] <cehteh> add drivers
[13:05:57] <eszett> without driver chip I cant drive alot LEDs?
[13:06:23] <cehteh> 40mA also stretches the limit, you can easily brown out the chip with that
[13:06:32] <eszett> I see..
[13:06:51] <cehteh> drivers are cheap
[13:06:59] <twnqx> like 7ct mosfets? :P
[13:07:41] <cehteh> google for uln2003 .. and then i forgotten the the types there are similar fet based things in pfet/nfet, that will do for matrix driven outputs
[13:08:02] <eszett> I was looking at the ISSI 31FL3733
[13:08:07] <cehteh> also there are drivers with latch or shift registers with drivers
[13:08:10] <eszett> 3 or 4 buucks a piece
[13:08:30] <cehteh> how many leds?
[13:08:39] <eszett> let me think..
[13:08:51] <eszett> 59 LEDs.. approx
[13:09:29] <eszett> the most economical LEDs consume about 5mA right?
[13:09:37] <cehteh> eh?
[13:09:45] <cehteh> depends on what brightness you need
[13:10:20] <eszett> standard brightness should be fine
[13:10:21] <cehteh> there are low current leds which work at 2mA or less at a brightness which is ok shadowy places
[13:10:30] <eszett> hmm..
[13:11:03] <cehteh> smd? through hole? 5mm?
[13:11:25] <eszett> SMD, 3mm if possible
[13:11:35] <cehteh> options options :D also the beam angle shoud be considered
[13:11:40] <eszett> 60 * 5mA = 300 mA should be ok
[13:11:59] <cehteh> when you matrix drive it not all are on at the same time
[13:12:18] <cehteh> depends on your driver
[13:12:37] <eszett> the driver switches them on and off alternatingly in very high frequency?
[13:13:18] <cehteh> matix only works when you interate over the rows
[13:13:26] <cehteh> (or columns .. whatever)
[13:13:38] <cehteh> and often one puts PWM over that for brightness controll
[13:13:43] <eszett> yes
[13:14:12] * eszett googles that uln2003 chip and how much it costs
[13:14:20] <cehteh> wont work for a matrix
[13:14:28] <eszett> uh
[13:14:43] <cehteh> you need one commaon anode and one cathode side
[13:15:10] <cehteh> *but* i know that there are similar fet based chips, in 2 types
[13:15:15] <cehteh> only forgot their names
[13:15:41] <cehteh> uln2003 is a bit too beefy too :) 500mA per pin
[13:15:57] <eszett> ah its a christmass tree driver
[13:16:01] <eszett> ;-)
[13:21:06] <cehteh> i think there are IC's specially suited for that task .. like the one you pasted earlier
[13:23:02] <eszett> ye.. Im reading the datasheet right now, thats fun
[13:24:00] <cehteh> when you get some serial bus, i2c or spi you need a lot less io's and worries, usually you have better brightness control etc ..
[13:24:37] <cehteh> ah this 7seggment display driver can also stacked for dotmatrix .. moment
[13:25:02] <eszett> unfortunately i have zero experience with i2c or spi :-(
[13:25:27] <cehteh> MAX7219
[13:26:21] <cehteh> https://www.amazon.de/gp/product/B00KKG7P98/
[13:27:07] <eszett> oops on cut tape this IC is above 10€ o_O
[13:27:08] <cehteh> drives 64 leds
[13:27:46] <cehteh> https://www.amazon.de/Hrph-Nahtlose-kaskadierbar-Arduino-MAX7219/dp/B01IMYG950/
[13:27:48] <cehteh> there you go
[13:28:31] <cehteh> https://www.amazon.de/MIKROE-1306-Expansion-board-mikroBUS-MAX7219
[13:28:43] <eszett> oh this one is a DIP, not even soldered but hot plugged into DIP soclets
[13:28:44] <cehteh> is that what you want?
[13:28:58] <eszett> for 2,70 € that is nice indeed
[13:28:59] <eszett> yes
[13:29:25] <cehteh> there are also RGB variants
[14:31:33] <carabia> https://hackaday.io/project/9976-dtto-explorer-modular-robot "search and rescue"?
[14:31:50] <carabia> jesus christ the people will die of starvation before this thing find them
[14:32:11] <carabia> finds even
[14:33:40] <specing> "self-reconfigurable" into a pile of junk?
[14:35:17] <carabia> it can be as self-reconfigurable as it can be while its stuck spinning in a crack between a bunch of rocks
[14:36:51] <carabia> perhaps it has a neural network -type of learning algorithm so when its stuck it can recite pseudo-intelligent bruce lee or art of war -quotes to itself
[14:37:47] <carabia> i would defo have dumped $150k on this
[14:56:47] <cehteh> lol
[15:15:04] <LeoNerd> I *think* I just successfully soldered a DFN8 chip
[15:15:31] * Lambda_Aurigae claps
[15:15:47] <LeoNerd> I would have used bigger but the chip literally only comes in this one size :/
[15:16:16] <Lambda_Aurigae> an attiny?
[15:16:20] <eszett> Leonard can you check the solder joints with magnifiers?
[15:16:45] <LeoNerd> Lambda_Aurigae: No; a MAX9643, it's a current-sense amp
[15:16:47] <LeoNerd> A reallllly nice one
[15:17:01] <LeoNerd> eszett: yup. did that. visually fine. no bridges between any neighbours
[15:17:06] <LeoNerd> tested electrically
[15:51:10] <eszett> nice..