**** BEGIN LOGGING AT Fri Nov 10 03:00:00 2017 Nov 10 03:15:35 How can I go to mode0 and mode3 w/ pin muxing? Nov 10 03:17:07 for pin P9_19 and P9_20? Nov 10 03:17:18 on a BBB? Nov 10 03:18:28 echo /sys/ and then what? Nov 10 03:31:41 set_: config-pin is not wrong, P9.23 has no i2c functionality Nov 10 03:34:00 the i2c on p9.19+p9.20 can't be easily disabled Nov 10 03:34:09 since it's used for CAPE identification Nov 10 03:35:15 Okay. Nov 10 03:35:22 capes shouldn't require any messing with config-pin though, they should get automatically detected and their pins configured Nov 10 03:35:49 The Motor Bridge Cape and the BBB have trouble, i.e. as far as I know. Nov 10 03:36:03 Communicating b/t these two devices has not worked for me yet. Nov 10 03:36:20 I can make it work w/ the BBG and BBGW. Nov 10 03:36:49 strange Nov 10 03:37:08 It is odd but I am writing a new image right now. Nov 10 03:37:22 you're running the same image on all of them? (to exclude software differences being the problem) Nov 10 03:37:30 no. Nov 10 03:38:02 Do you have a way to perform pin muxing? Nov 10 03:38:27 cat 3 /sys/blah/blah/blah/? Nov 10 03:38:30 Like so? Nov 10 03:38:36 Or another method? Nov 10 03:39:17 ... Nov 10 03:39:19 just use config-pin .. although as I just said, if any manual pin configuration is necessary for a cape, something is already wrong Nov 10 03:39:30 Okay. Nov 10 03:39:43 How do I change modes? Nov 10 03:40:18 error: question too vague Nov 10 03:40:34 Okay...How can I see which pin mux mode I am in and then change it? Nov 10 03:40:58 I looked at our SRM and their are many to choose from and if I wanted, I could change individual pins. Nov 10 03:41:02 But... Nov 10 03:41:11 use config-pin Nov 10 03:41:38 and of course you can get all details about current pinmux with my show-pins util Nov 10 03:41:48 Okay...I will try to enable pins w/ config-pin but I would rather use pin muxing w/ the BBB. Nov 10 03:41:50 ... Nov 10 03:42:07 zmatt: I have the exact same configuration from one BBB to a BBG. Nov 10 03:42:33 The...show-pins util is what I used. Nov 10 03:43:00 I found my pins and got that working but neither pin set-up was different. Nov 10 03:43:50 ... Nov 10 03:43:54 Do not worry about it. Nov 10 03:43:59 I will keep searching. Nov 10 03:44:00 if there are no differences in pinmux between the working and non-working case, why clearly whatever the problem is isn't a pinmux issue Nov 10 03:44:19 uhh, *then clearly... Nov 10 03:44:19 Okay... Nov 10 03:44:53 I will test the both capes on a third board. Nov 10 03:45:21 If something is wrong w/ the Cape, I will quit bothering us about the Cape issue. Nov 10 03:46:24 Or any other issue for that matter. But, if the Cape is functional and works and the BBB is the issue, I may need to individually change the pins. Nov 10 03:48:23 ... Nov 10 03:57:37 zmatt: What pins should I check on my two BBB boards to see if the connection is bad for Capes? Nov 10 03:58:14 P9_20 and P9_19? Nov 10 04:00:07 Luckily, I have two boards and two Motor Bridge Capes. This will ensure my knowledge of the working Cape versus a non-working Cape. Nov 10 04:19:44 ... Nov 10 04:20:06 I am testing the configuration for the MBC I know works w/ the BBG so far. Nov 10 04:20:17 ...I am going to test it after it reboots Nov 10 04:21:04 Now...off to test the MBC that works w/ the BBG w/ the BBB. Nov 10 04:24:01 No go...it is not the Cape. Nov 10 04:24:10 I have an issue w/ the BBB. Nov 10 04:24:14 <<<< clueless Nov 10 05:00:41 Otay! Nov 10 06:14:14 Does the data transfer rate for microUSB differ from 'normal' USB2? Nov 10 06:14:20 I assume not, but I'm not sure. Nov 10 06:27:57 the size of the connector doesn't affect the maximum transfer speed. The protocol does Nov 10 06:28:36 Also the actual speed will depend on if the CPU can shovel data fast enough into the USB controller Nov 10 06:37:59 tbr: I ask because I'm curious about the PocketBeagle with a microUSB breakout, like here: https://github.com/beagleboard/pocketbeagle/wiki/FAQ#How_do_I_get_additional_USB_connections Nov 10 06:39:30 zmatt: thanks Nov 10 06:48:18 Also, is there some kind of guide or set of guides to understanding how to use expansion headers? I have no idea what any of that stuff means... Nov 10 07:21:46 docs on the pocketbeagle specifically are probably still a bit limited I think, since it's fairly new Nov 10 07:22:00 (I could be wrong, I haven't looked really since I don't have a pocketbeagle) Nov 10 07:22:42 your question is also a bit vague Nov 10 07:32:34 koz_: you can hook up any physical shape USB port to those pins. It will act as a USB2 host port. Nov 10 07:42:11 has anyone done eye diagram measurements of the USB break out on the pocketbeagle? Nov 10 07:42:39 wonder how decent is the noise margin with that sort of routing Nov 10 07:47:00 tbr: actually, to make it a host port you need an external power switch, not just a connector Nov 10 07:47:12 ds2: yup Nov 10 07:47:28 (as in, yup that would be interesting, not yup I did measurements :P ) Nov 10 07:47:55 oh.... :( I was so looking to asking if you took screen shots! Nov 10 07:48:24 zmatt: would you happen to know a quick and dirty way of doing with a scope? Nov 10 07:50:19 it would probably be fiddly to find a good trigger Nov 10 07:50:57 just find someone with usb verification gear Nov 10 07:51:10 zmatt: yeah, I'd probably only feed d+/d- into a powered hub anyway. Nov 10 07:51:12 that's of course always the best option if it's available Nov 10 07:51:20 tbr: that wouldn't help Nov 10 07:51:44 tbr: the usb controller expects to be able to switch the 5v power and see the results measured back on its vbus input Nov 10 07:51:56 ah Nov 10 07:52:07 on omap3 you could get away with such shenanigans Nov 10 07:52:26 I think it may be possible to override it, but I don't know if the linux driver supports it Nov 10 07:52:33 iirc such an override is considered a test mode Nov 10 08:02:34 tbr: Which pins exactly? I'm planning to use a https://www.adafruit.com/product/1833. Nov 10 08:03:56 the ones that the FAQ mentions obviously Nov 10 08:04:35 as zmatt says, you might need to figure out the VBus switching. Looking at the BBB schematics might help in that respect Nov 10 08:05:31 tbr: I'm really out of my depth here - is there any sort of reading I can do to better understand ... well, whatever this is called? Nov 10 08:05:52 electrical engineering? ;-) Nov 10 08:06:21 tbr: Well, yes, but that's rather broad. Nov 10 08:06:46 read the AM335x TRM Nov 10 08:06:55 ds2: TRM? Nov 10 08:07:10 oh the FAQ is suggesting to use a breakout with vbus hardwired to 5v ? I'm pretty sure someone tried that and it resulted in problems Nov 10 08:07:14 technical reference manual Nov 10 08:07:15 if you want things to work reliably on USB2.0 HS, read the specs on electrical requirements or you maybe surprised in a bad way Nov 10 08:07:36 koz_: yeah...the tech ref manual from TI.. it is THE bible for the processor Nov 10 08:07:59 zmatt: One of the reasons I'm asking - I saw that the pin was labelled 5V, but the 'power' pins on the PocketBeagle are 3.3. Nov 10 08:08:02 koz_: the short story: adding the extra usb port is really not a simple matter Nov 10 08:08:19 koz_: no they did connect it to a 5v supply pin Nov 10 08:08:19 zmatt: well... simple is a matter of prospective Nov 10 08:08:23 zmatt: That is the impression I'm getting, yes. Nov 10 08:10:03 zmatt: I'm looking at the diagram, and it shows two red lines going into the 5V on the breakout. What do those correspond to? Are they pins 5 and 7 on the P1? Nov 10 08:10:30 yes Nov 10 08:10:57 zmatt: They're labelled VBUS and VIN - am I missing something? Nov 10 08:11:28 iirc VIN is referring to the 5v input from the usb connector on the pocketbeagle Nov 10 08:11:59 So it stands for 'voltage in' or something? Nov 10 08:12:49 in general it's common to give supply nets a name that starts with a v Nov 10 08:13:11 Ah. Nov 10 08:13:11 so vin should be read as "input supply" or something like that Nov 10 08:13:34 OK, I'll remember that for the future. Nov 10 08:14:05 So looking at this diagram: https://raw.githubusercontent.com/wiki/beagleboard/pocketbeagle/images/PocketBeagle_pinout.png , I assume this means that there's only pins for 1 more USB, right? Nov 10 08:14:17 yes, the am335x has 2 usb ports total Nov 10 08:14:33 OK, that makes a lot more sense now - thank you! Nov 10 08:14:47 Also, what does AIN refer to? Nov 10 08:14:56 analog inputs Nov 10 08:14:56 analog input Nov 10 08:15:08 Ah, so for like radio signals and stuff? Nov 10 08:15:26 it can't sample that fast Nov 10 08:15:37 So what could they be used for? Nov 10 08:16:34 ain as in ADC? be very careful with those. They are very sensitive to over-voltage. Nov 10 08:17:01 lots of things, for example there are temperature sensors with an analog output signal Nov 10 08:17:17 touch screens Nov 10 08:17:22 that too indeed Nov 10 08:17:29 (resistive touchscreens) Nov 10 08:17:32 IR distance sensors Nov 10 08:17:39 battery levels Nov 10 08:17:51 (with careful processing/scaling of course!) Nov 10 08:17:58 OK, that makes sense. I guess I should have expected that touchscreens are analog. Nov 10 08:18:39 What does PWM refer to? Nov 10 08:18:51 (sorry if these questions sound daft - I'm a complete newbie) Nov 10 08:18:52 but as tbr said, they do need to be handled with care. the analog inputs of the am335x run on a 1.8v supply and do not tolerate being exposed to voltages outside 0-1.8v Nov 10 08:18:57 consider googling before asking Nov 10 08:20:09 most of these abbreviations (pwm, uart, spi, i2c, gpio) should yield plenty of info Nov 10 08:20:27 PRU doesn't, but yes, the others do. Nov 10 08:20:34 pru being a notable exception yes Nov 10 08:20:36 and qep Nov 10 08:20:45 What are those, then? Nov 10 08:21:33 qep inputs are for quadrature signals from a rotary encoding (you can google that) Nov 10 08:21:45 also usable for pulse-counting or frequency measurement Nov 10 08:22:58 pru stands for programmable real-time unit. it's a special subsystem of the am335x Nov 10 08:23:22 it contains two small cpus capable of reacting to stuff very quickly and consistently Nov 10 08:23:34 And those pins can feed them signals? Nov 10 08:23:43 they have dedicated i/o signals yeah Nov 10 08:24:15 It seems you can do lots of cool things with a PocketBeagle. Nov 10 08:25:00 for comparison, having a linux processor trigger on a gpio took about 40-80 microseconds last time I measured it Nov 10 08:25:03 *process Nov 10 08:25:13 And how fast would the PRUs be? Nov 10 08:26:31 iirc I measured it around 30 ns roundtrip time input -> output, and probably a significant part of that is propagation delay on the inputs/outputs themselves Nov 10 08:26:46 I see what you mean about 'quickly'... Nov 10 08:26:59 How are the units programmed? Do I have to feed them the program over a serial line or something? Nov 10 08:27:51 nono, they're an integral part of the am335x, so you can actually mmap() the memories and control registers of the pru subsystem into a linux process Nov 10 08:29:55 Neat, that's much easier then. Nov 10 08:29:56 that tight integration is also how things like BeagleLogic are possible (a software project that uses PRU to turn a beaglebone into a 14-channel 100Msps logic analyzer) Nov 10 08:30:40 be warned that the BBB only can handle 3.3V as a logic analyzer without additional hardware Nov 10 08:31:33 zmatt: I bet you can have a "software" project do faster then 100Msps using a Zynq processor too ;) Nov 10 08:33:00 yeah, in general never expose i/o pins to voltages significantly greater than the corresponding supply. that means 3.3v (or 1.8v for analog inputs) when the beagle is powered, and 0v when it's unpowered Nov 10 08:35:45 Alrighty, I shall keep reading. Thank you for all the explanations! Nov 10 08:37:22 the pocketbeagle (unlike beaglebones) also has some 3.3v analog inputs (they simply have a voltage divider to scale the voltage down to 1.8v ) Nov 10 08:39:05 Like pin 14 on P1? Nov 10 08:39:37 that's not an analog input, it's a supply pin Nov 10 08:39:55 Oh, whoops. Nov 10 08:39:59 analog inputs are marked in yellow Nov 10 08:40:39 P1.2 and P2.35 are the ones that are 3.3v Nov 10 08:41:03 Ah, I see. Nov 10 08:41:07 ds2: not sure about that, when I played with zynq (or FPGAs in general) about 100MHz was the maximum clock. Nov 10 08:41:19 Is there some kind of standard to those diagrams in terms of colour-coding I'm not aware of? Nov 10 08:41:32 actually, I should say the yellow-marked pins are adc-related. P1.17 and P1.18 aren't inputs Nov 10 08:41:41 no Nov 10 08:42:09 ds2: I think there's a Siglent DSO that does 1Gs/s or thereabouts on a Zynq7000 platform Nov 10 08:42:40 ds2: basic two channel scope with I think 100MHz analog bandwidth Nov 10 16:00:49 do you know how to use putty? Nov 10 23:57:10 Hello Nov 10 23:57:32 I am trying to change the SSID of my Beaglebone Green Wireless Nov 10 23:57:59 Can anybody please help me with that Nov 11 00:16:09 Neha__: this might get you started https://elinux.org/BBBWiFiConfigs **** ENDING LOGGING AT Sat Nov 11 03:00:02 2017