**** BEGIN LOGGING AT Sun Jan 19 03:00:00 2014 Jan 19 08:07:24 Hi, my beaglebone black goes dead when i flash its eMMC with Angstrom (2013-06-20) but works fine when i boot it from uSD card Jan 19 08:20:14 Guest77571: what do you do to flash? Jan 19 08:20:17 meeeh Jan 19 08:49:18 I am using R30 on the pru to set a pin and low, and I am trying to do so with precise timing, is there any lag (more than a few microseconds) between twiddling the bits of R30 and the pin going high? Jan 19 08:59:28 the pru being for real-time things, I'd hope that stuff happens instantly ;) Jan 19 09:02:43 that would make sense, this thing is just driving me nuts, I must be converting microseconds to instruction counts wrong or something Jan 19 09:03:53 <_av500_> well, if the lag is fixed, it's still precise timing Jan 19 09:55:56 how would one go about installing libusb-dev on bbb ? Jan 19 09:56:11 need it for gphoto2. Jan 19 10:01:25 anujdeshpande: have you tried opkg install libusb-dev? Jan 19 10:01:37 (if it's in the package manager) Jan 19 10:01:52 its not in the package manager :) Jan 19 10:02:14 like most of stuff :-/ Jan 19 10:02:22 bah ... compil it from source :-) Jan 19 10:02:51 did you update the index first? Jan 19 10:04:08 tbr, opkg search libusb-dev return nothing Jan 19 10:05:02 angstrom seems to need some packagers monkeys ... Jan 19 10:08:02 tbr aurelien i got it after an opkg update Jan 19 10:08:05 thanks ! Jan 19 10:08:16 :) Jan 19 10:08:47 why opkg search libusb-dev does not list it to me? Jan 19 10:09:25 opkg update first Jan 19 10:09:43 i have opkg update first Jan 19 10:10:12 # opkg update && opkg search libusb-dev Jan 19 10:10:49 just do libusb Jan 19 10:10:57 version number in between Jan 19 10:11:15 nop Jan 19 10:12:18 http://pastie.org/8647372 Jan 19 10:15:23 it's the original angstrom ... so what is going wrong? -_-' Jan 19 10:30:44 an idea why angstrom does not give it to me on search? Jan 19 10:30:56 http://pastie.org/8647372 Jan 19 10:32:44 aurelien i am runnin the latest image Jan 19 10:33:47 bbb:~$ uname -a Jan 19 10:33:49 Linux bbb 3.8.13 #1 SMP Thu Sep 12 10:27:06 CEST 2013 armv7l GNU/Linux Jan 19 10:33:57 that is not the last one? Jan 19 10:34:27 opkg update && opkg upgrade does not give the last one? Jan 19 10:35:20 i have the same Jan 19 10:35:37 :-/ Jan 19 10:43:29 weird Jan 19 10:45:01 * aurelien have certainly missed a point -_-' Jan 19 10:47:32 Any advice on how to start contributing to BeagleBoard? I don't mean GSoC. Jan 19 11:23:26 p0ff: pick a project from the projects page Jan 19 13:53:40 after loading device tree overlay for P8_13 as pwm Jan 19 13:53:52 need I echo it to the export file? Jan 19 14:03:21 ok, I got the pwm to work, I am trying to drive a piezo electric buzzer with it Jan 19 14:03:33 I connect it to P8_13 and DGND Jan 19 14:03:40 I get no sound Jan 19 14:03:46 any help? Jan 19 14:29:16 good morning! Jan 19 17:18:49 hello Jan 19 17:21:11 has anyone here worked with the pruss? Jan 19 17:22:21 I can't get inputs to work, I have the device tree files up, and I can see they are configured correctly, with grep Jan 19 17:23:07 but it doesn't work with my python script and assembly script, I can only control outputs Jan 19 17:55:43 Hi guys Jan 19 17:56:43 Does anyone can tell me the difference between the beaglebone et beaglebone Black ? Plz Jan 19 18:00:28 black is faster, more ram Jan 19 18:02:10 hi #beagle! today i've got a hardware question. i got a coil and a magnet, which is going to move through the coil, inducing a voltage on the two outputs of the coil. i want to measure this with my beaglebone blacks AIN pins. 1. how would i have to attach the coil wires? one to AIN0 and one to the ADC-ground? 2. i did some tests and the voltage does not exceed 1.8V so this should be safe. but what about negative voltages? ie. when movi Jan 19 18:02:15 direction, the voltage will be reverse. will this damage my BBB? Jan 19 18:11:02 anyone? don't want to destroy my bone... Jan 19 18:12:06 i wouldn’t Jan 19 18:12:24 i applied 3v to ground (not adc-ground) and it fried Jan 19 18:13:19 yes i've seen all these red warnings in the SRM, so im extra careful here Jan 19 18:13:39 i wouldn’t attempt it Jan 19 18:13:44 unfurtunatly, i cant find anything about reverse voltages Jan 19 18:17:55 ssl_: negative voltage will be clamped by clamp diodes and at least damage those if yo have enough energy Jan 19 18:18:21 ssl_: and after damaging clamp diodes there will be nothing stopping it from frying rest of the chip Jan 19 18:19:04 ssl_: you either have to DC bias it or have active rectifier circuit Jan 19 18:19:21 ssl_: and feed it through at least 10k resistor Jan 19 18:19:57 i guess that "have enough energy" part is very important, since the magnet is not moving very fast, i dont think i can damage anything Jan 19 18:20:05 oh yes you can Jan 19 18:20:14 those diodes are only few atoms in size Jan 19 18:20:43 oh well Jan 19 18:20:49 basically, negative voltages into any input pins is a no go Jan 19 18:21:03 ok thanks for that clear statement Jan 19 18:22:18 hey guys Jan 19 18:22:38 does anyone work with the PRUs using Python? Jan 19 18:26:09 ssl_: all you need is add a DC bias that is high enough and then just use resistor divider to keep it within range Jan 19 18:27:02 ssl_: https://en.wikipedia.org/wiki/Bias_tee Jan 19 18:27:35 although i'm not sure how well it will work in your application Jan 19 18:27:45 you may need some different way of biasing it Jan 19 18:28:14 ill look into that, thanks Jan 19 18:28:58 so basicly i need to add a 0.9 volts to my original input so that it's in 0-1.8 v range Jan 19 18:29:12 yes Jan 19 18:31:17 ssl_: besides, look at absolute maximum ratings Jan 19 18:31:25 Steady State Max. Voltage -0.5V to IO supply voltage + 0.3 V Jan 19 18:31:51 what do these mean? Jan 19 18:32:04 and absolute maximum means exactly that, exceeding it by any amount means destruction of the chip Jan 19 18:34:04 http://www.ti.com/lit/ds/symlink/am3358.pdf - page 80 Jan 19 18:35:11 im not really into electronics, but what about if i take the 1.8v from the adc, but two equal and high resistance resistors (voltage-divider!?) so i get the required 0.9v. only question is how to add them to my signal :D Jan 19 19:38:55 is my math correct, a simple loop MOV R1, 900000; FOO: ; SUB R1, R1, 1; QBNE FOO, R1, 0 in pru asm should run for 9000 microseconds? Jan 19 19:48:59 <_av500_> what is FOO? Jan 19 19:51:01 So, anyone got a working BBB for sale in the UK? Jan 19 19:52:34 I would like to buy a unicorn, some rocking horse p** and a BBB... Jan 19 19:53:36 Some hen's teeth too Jan 19 19:53:49 fresh out of these Jan 19 19:55:16 The unicorn, rocking horse p**, hens teeth or BBB? Jan 19 19:56:30 all of it Jan 19 19:56:35 :( Jan 19 19:56:41 there seems to be some sort of limited availability in general Jan 19 19:57:27 Yeah, was wondering if anyone wanted to sell one on here... Jan 19 20:17:23 <_av500_> how much do you offer? Jan 19 20:18:52 av500: FOO is a label, there is a FOO: at the top of the loop Jan 19 20:20:20 I have this C code that pulses a pin with timings on the order of hundreds of microseconds, and I am trying to replace it with code that runs on the pru, but it doesn't seem to be working Jan 19 20:24:26 seems like are 2 instructions in the loop, 5ns per instruction, 10ns per loop, 9000 microseconds * 1000 = 9,000,000 nanoseconds, 9000000 nanoseconds / 10 ns per loop body = 900000 loops Jan 19 20:36:26 _av500_, let the bidding begin Jan 19 20:47:17 hiredman, looks good Jan 19 21:01:09 I wonder if maybe it isn't working right because the pru is in shift out mode instead of direct connection, anyone know off hand how to ensure the pru is in direct out mode? Jan 19 21:01:28 I guess the manual says direct is the default :/ Jan 19 21:03:46 it is Jan 19 21:06:20 mdp: do you know if toggling pins via R30 has some kind of lag? Jan 19 21:06:46 logic analyzer Jan 19 21:08:04 I don't have one Jan 19 21:28:08 Hey, is it possible to install debian on a beaglebone? Jan 19 21:31:24 Yes. Jan 19 21:50:30 I have a question about interfacing with an I2C DAC (the MCP2725). I'm looking at some code for the Raspberry Pi; they set a voltage maximum at 4095 and I can't figure out where they got that number from Jan 19 21:51:29 That would be the maximum value of a 12-bit number. Jan 19 21:51:43 My guess is your DAC has 12 bits of resolution. Jan 19 21:54:18 Yes it is. So just 2**12 ~ 4095 ? Jan 19 21:54:33 No. Jan 19 21:54:40 2**12 = 4096. Jan 19 21:54:54 right, they're setting it to 2095 Jan 19 21:54:55 But since 0 is a possible value, you get a range of 0 to 4095. Jan 19 21:55:03 ahhhh, rodger that Jan 19 21:55:09 4096 possible values. Jan 19 21:55:47 okay, thank you for your help! Jan 19 21:55:55 <_av500_> hiredman: ah yes, ignore :) Jan 19 23:35:33 hello Jan 19 23:35:42 I need some help Jan 19 23:35:45 :) Jan 20 00:33:57 hi Jan 20 00:38:15 hey any security guys in here? Jan 20 00:40:05 breaches on the BBB would be through the power supply, right? Jan 20 00:40:48 Would they? Jan 20 00:44:45 anybody knows how to use spi on BBB with debian? I've tried all i could search for 2 days but nothing works... Jan 20 00:47:25 suppose so...unless someone knows otherwise. Flat-screen entry-point? Real-time, I mean. Jan 20 00:51:31 stumped_with_per: Seems like working too hard, when you could, you know, just attack the OS. Jan 20 00:53:31 Well that's no mean feat...where would I start with that? Book about the Linux kernel? Jan 20 00:54:42 I suggest Googling "Linux script kiddie warez" Jan 20 00:54:47 lol Jan 20 00:55:53 yeah you have to hack through the flat screen, by pressing the screen buttons in a very specific order Jan 20 00:56:03 in real time Jan 20 00:56:42 you're on the right track, stumped_with_per. keep at it :) Jan 20 00:57:15 perl..maybe there's a limit on the characters in the nick Jan 20 00:57:30 ! Jan 20 00:57:50 Hmmm, you seem to have very definite ideas on security grantsmith Jan 20 00:58:08 Are you one of those people with nothing to hide? Jan 20 00:59:42 And banhammer in 3...2.. Jan 20 01:02:52 On a related matter - the BBB and friends are an interesting platform to practice differential power attacks of various sorts on. Jan 20 01:03:17 I was most amused to come acrosss a DPA in a book. Jan 20 01:03:31 A fantasy book - against a magical object. Jan 20 01:26:27 and.. briefly disconnected :/ Jan 20 02:46:13 what are my options in adding additional rj45 jacks? Jan 20 02:46:21 to beaglebone black **** ENDING LOGGING AT Mon Jan 20 02:59:59 2014