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[06:40:27] <averowsky> anyone experienced what would be better for balancing robot: stepper motors or dc motors with encoders ?
[07:00:18] <osteri> averowsky: encoders are used with those, because of feedback
[07:01:01] <osteri> search for "PID motor controller"
[07:08:11] <averowsky> osteri: basically I have working balncing robot, but i have very cheap plastic dc motors
[07:08:29] <averowsky> which are not too fast and I think torque is to small
[07:08:50] <osteri> torque might be a problem
[07:08:59] <averowsky> so I need to buy something new and because motors are not cheap I would like to hear someone opinion
[07:10:20] <averowsky> and I think it is
[07:10:35] <averowsky> so I will try to decrease weight
[09:41:59] <gorroth> awozniak: i don't know the answer to your question, but if you go with 24v 350w motors, you can get them for less than 50 usd each
[09:42:13] <gorroth> that would help with expense of motors, awozniak
[09:56:48] <osteri> not wozniak ;)
[10:24:58] <gorroth> oops!
[10:25:22] <gorroth> wozniak and verowsky look very similar when i'm not paying attn :)
[10:49:53] <LeoNerd> [OT]: The 4066 chip contains 4 independent SPST analog switches. I'm after some SPDT switches, but I don't need independent control; I'm happy with one control for all four simultaneously. Does anyone know of such a chip?
[11:06:56] <LeoNerd> Mm.. MAX394 looks plausible. Four independent SPDTs
[11:07:32] <LeoNerd> Ooooh.. or maybe if I could find a 4x4 crosspoint switch
[12:31:13] <LeoNerd> Hrm.. so... the thing I'm after isn't a true "crossbar" switch, it's more of a "permutation switch". I have four "input" channels and four "output" channels; I want a switch that lets me aribtrary plug them in some permutation
[12:31:43] <LeoNerd> So.. I'll never need to route one given input into multiple outputs, or vice versa, but I'd like to have arbitrary choice of which input goes to which (unique) output
[12:32:04] <LeoNerd> I know a crossbar switch would give me that, but that might be overspeced if I can find what I want easier
[12:33:47] <LeoNerd> A full crossbar switch would presumably need 16 bits of (perhaps serially clocked by SPI?) configuration information, whereas this permutation muxer needs just under 5 bits; 2 bits to select the input channel used by output A, 2 bits to select the remaining input used by B, then 1 bit to select C and the choice of D is now determined. Though perhaps four independent 1-of-4 MUXers in one chip might suffice, at 8 >>
[12:33:47] <LeoNerd> << configuration bits
[13:13:06] <Jartza> evening
[13:13:42] <Jartza> anybody thinks I could use st662abd for powerboosting enough to make HVSP?
[13:14:05] <Jartza> that chip is used to boost for +12V
[13:18:09] <Jartza> oops
[13:18:20] <Jartza> internet-glitch in the middle of sentence :)
[13:18:40] <Jartza> that chip is used to boost 5V to 12V for eeprom writing, maybe it works for AVR too
[13:30:31] <RikusW> Jartza: I used it, it works fine
[13:30:34] <LeoNerd> Jartza: I use exactly that
[13:30:49] <LeoNerd> Well, no.. I use the pinwise-compatible but cheaper LTC.. er.. something. Let me remind myself
[13:31:20] <LeoNerd> LTC1262
[13:31:23] <Jartza> mmkay
[13:31:24] <RikusW> I added a 1k5 resistor from the output of the 662 and a transistor to pull it down
[13:31:35] <RikusW> so I can select 0 5 or 12V
[13:31:51] <LeoNerd> https://www.tindie.com/products/leonerd/avr-hvsp-programming-bus-pirate-adapter/ <== my one :)
[13:31:53] <Jartza> mkay
[13:32:09] <RikusW> with the 1k5 even connecting to the wrong pin on an avr, there shouldn't be any damage
[13:32:16] <LeoNerd> You can just see the 1262 at the top right corner of the board
[13:32:52] <RikusW> Jartza: my boards
https://sites.google.com/site/megau2s/
[13:33:09] <RikusW> there are schematics and photos
[13:33:17] <LeoNerd> RikusW: Oh, while you're here: my latest one of [theabove] I made up works fine for the 8pin tiny85 but is failing to burn a 14pin tiny84. Do you recall any reason that might be the case?
[13:33:40] <LeoNerd> It's the same standard circuit as all the others, so I'm suspecting a dodgy solder joint on a pin, or some other kind of odd upset
[13:33:52] * RikusW peeks at some datasheets
[13:34:20] <Jartza> RikusW: ohh... that's ready hvsp/hvpp programmer?
[13:34:33] <RikusW> yep
[13:34:39] <RikusW> STK500 clone
[13:34:50] <RikusW> and JTAG ICE mki clone
[13:35:09] <Jartza> do you still have them?
[13:35:32] <Jartza> why on earth make my own if you have them :)
[13:36:03] <RikusW> LeoNerd: Did you connect the t84 PA0,1,2 to ground ?
[13:36:08] <LeoNerd> Yup. Via 2k2
[13:36:28] <RikusW> in the ds its connected directly to ground
[13:36:41] <RikusW> Jartza: I still have like 80
[13:36:54] <Jartza> and you sell them?
[13:37:07] <RikusW> and 16 or so sets of topboards
[13:37:15] <RikusW> (still unassembled)
[13:37:35] <RikusW> yep
[13:37:44] <LeoNerd> I sell mine, yup
[13:37:51] <Jartza> unassembled is fine
[13:38:07] <LeoNerd> Though mine is rather special-purposed to just do 8- and 14-pin ATtinys
[13:38:09] <RikusW> I'll assemble those, just never got around to it ;)
[13:38:17] <RikusW> I have all the smd parts
[13:38:30] <Jartza> RikusW: so, how much for one "full set" with topboards?
[13:38:39] <RikusW> ZAR 300
[13:38:56] <Jartza> ~20€
[13:38:59] <Jartza> I'll take it :)
[13:39:03] <RikusW> roughtly $23
[13:39:37] <Jartza> and shipping to finland?
[13:39:44] <RikusW> no idea on that...
[13:40:01] <Jartza> should be standard EU rate
[13:40:52] <RikusW> I'll inquire about it
[13:41:02] <RikusW> DHL will be pricy...
[13:41:08] <Jartza> no need for DHL
[13:41:33] <RikusW> I did send one U2S to vectory some years ago
[13:42:02] <RikusW> using standard mail
[13:42:43] <Jartza> std. mail is just fine, I'm not in a hurry
[13:43:24] <Jartza> but I only have arduino and external 12v supply assembled on breadboard with scratchmonkey currently for hvsp and I find it "not so pretty" option
[13:43:36] <Jartza> and stk600 is absurdly priced :)
[13:43:53] <RikusW> Which sw are you using with it ?
[13:44:00] <RikusW> studio or avrdude ?
[13:44:14] <Jartza> avrdude
[13:44:17] <Jartza> I'm on mac
[13:44:21] <RikusW> ah
[13:44:40] <RikusW> I'm not entirely sure whether studio 7 supports stk500... :/
[13:44:51] <Jartza> no idea
[13:44:58] <Jartza> and I don't care :)
[13:45:00] <RikusW> I had to generate some xml files to add device support for studio 5/6
[13:45:17] <RikusW> it works fine with avrdude
[13:45:42] <Jartza> that's all fine for me :)
[13:45:54] <Jartza> just tell me where to pay and where to give my address and what's the sum :)
[13:45:56] <RikusW> There is even Altera USBBlaster code for the U2S
[13:45:59] <Jartza> and I buy one
[13:47:31] <RikusW> Jartza: im
[13:48:22] <RikusW> I'll assemble and test the boards over the weekend
[13:49:18] <Jartza> that's very nice
[13:51:59] <RikusW> have you ever played with fpga/cpld ?
[13:52:22] <Jartza> not yet
[13:52:26] <Jartza> been thinking about it for a long time
[13:52:31] <Jartza> but haven't had time
[13:52:40] <RikusW> I've gotten some cheap Altera CPLD board that I used to test my USBBlaster code on, haven't gotten much further though
[13:52:57] <RikusW> using Altera sw got a steep learning curve...
[13:53:23] <Jartza> I guess any fpga has :)
[13:53:27] <RikusW> and verilog/vhdl... verilog looks C like, but it is much different
[13:56:21] <RikusW> Jartza: the HVPP board got the same pinout as a dragon, so the same docs apply
[13:56:44] <Jartza> nice
[13:57:14] <RikusW> I cheated on writing docs, and just used Atmels :-P
[13:57:20] <Jartza> hehe
[13:57:35] <Jartza> laziness is one of the main qualities of designer/programmer
[13:57:58] <Jartza> it's not cheating. it's called being productive :)
[13:58:06] <RikusW> indeed :)
[13:58:18] <apo_> until it impairs quality =P
[13:58:47] <RikusW> The PCB screen capture is also on the site, so all pins are documented :-P
[13:59:36] <RikusW> the boards are fairly simple, but since m32u2 is tqfp only a PCB is required..
[14:02:22] <RikusW> U2S is more or less a breakout + all essential components and some extra fw
[14:02:49] <RikusW> Jartza: ever done USB programming ?
[14:08:42] <Jartza> RikusW: usb programming as in? USB-stack?
[14:09:13] <RikusW> yes
[14:09:48] <RikusW> I took my CDC code from the Atmel CDC demo, then converted it to asm in 800 bytes
[14:10:03] <RikusW> Atmel's was over 5kb
[14:30:27] <Jartza> yea, that's nice :)