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by secretagent
Tue Aug 14, 2012 10:04 am
Forum: Troubleshooting
Topic: Kernel paging error during heavy network and disk load
Replies: 22
Views: 6484

Re: Kernel paging error during heavy network and disk load

I can post instructions on how to run Kdump on the Pi, which would let users experiencing kernel crashes, such as this, to send complete memory dumps of the crashed kernel for developers to look at. However there is one caveat: this requires a bit of RAM to be reserved for the crashkernel, so that R...
by secretagent
Tue Aug 14, 2012 9:39 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: FTDI USB Serial Hangs
Replies: 137
Views: 133072

Re: FTDI USB Serial Hangs

Ubuntu doesn't run on the Pi as far as I'm aware (at least no recent version). Do you mean Ubuntu on the PC ? or Are you running 9.04 ? If the former, indeed, there is no problem on the PC platform, and in fact I understand there is no issue on other ARM platforms, the issue is Pi (or USB Controlle...
by secretagent
Tue Aug 14, 2012 9:31 am
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 215288

Re: USB - the Elephant in our Room

... Can you supply information on the particular PS2 adapter you are using, might make it easier to see what the problem is. Also, do USB keyboards/mice work ok? Which should prove whether it's the adapter or not. It is one of these . I don't have any USB keyboards or mice, which is why I bought th...
by secretagent
Sat Aug 11, 2012 12:25 am
Forum: Troubleshooting
Topic: USB packet loss.
Replies: 253
Views: 54648

Re: USB packet loss.

Maybe a USB addendum for CRC on data, and a packet order. Packet loss is an endemic radio crackle problem. Anything which can not deal with this natural crackle possibility is not living in the analog world, but assuming digital perfection. After all burst packet data would not get as far on a USB ...
by secretagent
Fri Aug 10, 2012 2:57 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: FTDI USB Serial Hangs
Replies: 137
Views: 133072

Re: FTDI USB Serial Hangs [Solved]

The problem is definitely with the DWC_otg driver (the driver for the Pi's USB hardware). It looks like sometimes the channel gets halted without the reason being known, so the driver doesn't know what to do with it and as a result doesn't do anything, which apparently causes the hanging. I tried fo...
by secretagent
Thu Aug 09, 2012 10:12 pm
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 215288

Re: USB - the Elephant in our Room

What interesting is that this driver was supplied by Synopsis, and not by the Foundation or Broadcom. The Synopsis Verilog is used quite a lot in the field, as is this driver. And yet, the problem is only really coming to light now. And yet, looks who's getting all the grief.... I could be wrong bu...
by secretagent
Thu Aug 09, 2012 10:50 am
Forum: C/C++
Topic: GPU Processing API
Replies: 124
Views: 35058

Re: GPU Processing API

I doubt that a third party attempting to disassemble the GPU code (ie not the Foundation who have access anyway) would affect the Foundation/Broadcom relationship at all. However, if done in the USA anyone doing so would have to be very careful about the DMCA implications. Although that is my opini...
by secretagent
Wed Aug 08, 2012 10:35 pm
Forum: C/C++
Topic: GPU Processing API
Replies: 124
Views: 35058

Re: GPU Processing API

And who said anything about suing people? This is probably the thread in question: http://www.raspberrypi.org/phpBB3//viewtopic.php?f=72&t=13457 And I think the point is not so much about litigation (although anything is possible these days) but about possibly causing deterioration in the relations...
by secretagent
Thu Aug 02, 2012 4:29 pm
Forum: General discussion
Topic: Getting past TSA in the USA
Replies: 21
Views: 9924

Re: Getting past TSA in the USA

I've gone through TSA (coming from outside of the USA) with dozens of custom made boards in my carry-on without a problem. Sometimes they ask what are they going to be used for but that's it. It is good to have as much documentation as possible. If you have the descriptions sheets that came with the...
by secretagent
Thu Aug 02, 2012 4:18 pm
Forum: Troubleshooting
Topic: USB redirector
Replies: 71
Views: 60319

Re: USB redirector

Sorry, missed the notification somehow. Yes, there are many things that will fail without a swap, so I've always had it enabled and forgot to mention it in the instructions. I can't help with the windows client but if you want to make sure that the setup on the Pi is correct you could run a ubuntu l...
by secretagent
Sun Jul 15, 2012 3:26 pm
Forum: C/C++
Topic: GPIO Programming and Interrupts
Replies: 64
Views: 27876

Re: GPIO Programming and Interrupts

There is an example that works on the pi here: https://www.ridgerun.com/developer/wiki ... int-test.c
by secretagent
Thu Jul 12, 2012 12:08 pm
Forum: Troubleshooting
Topic: USB redirector
Replies: 71
Views: 60319

Re: USB redirector

There is a windows client on their website: http://usbip.sourceforge.net/ although I have never used it.
by secretagent
Thu Jul 12, 2012 11:40 am
Forum: Troubleshooting
Topic: USB redirector
Replies: 71
Views: 60319

Re: USB redirector

Here is how to get USBIP working on raspberry pi: Note: I have only done this on the debian wheezy beta. May or may not work on anything else. Compiling the drivers (if the official kernel enables the modules this step will not be necessary): First, make sure you have updated to the latest kernel, m...
by secretagent
Thu Jul 12, 2012 11:28 am
Forum: Troubleshooting
Topic: Unload smsc95xx
Replies: 6
Views: 4340

Re: Unload smsc95xx

itimpi wrote:Isn't that the module that drives the SD card? If so removing it is likely to cause severe problems.
No, it's the network driver.
by secretagent
Thu Jul 12, 2012 12:13 am
Forum: Troubleshooting
Topic: Unload smsc95xx
Replies: 6
Views: 4340

Re: Unload smsc95xx

You can try this to disable it:

Code: Select all

echo 1-1.1:1.0 > /sys/bus/usb/drivers/smsc95xx/unbind
and to enable it back:

Code: Select all

echo 1-1.1:1.0 > /sys/bus/usb/drivers/smsc95xx/bind
by secretagent
Wed Jul 11, 2012 9:37 am
Forum: Automation, sensing and robotics
Topic: Panalyzer - a RaspberryPi based Logic Analyzer
Replies: 69
Views: 44870

Re: Panalyzer - a RaspberryPi based Logic Analyzer

Thanks very much Richard for your detailed analysis! This answers the questions I had about the RPi hardware capabilities. The 250 MHz counter rate got me excited, but it seems that timing resolution cannot be put to use in any simple way to time-stamp an incoming edge with anything better than abo...
by secretagent
Sun Jul 08, 2012 11:32 pm
Forum: Automation, sensing and robotics
Topic: Panalyzer - a RaspberryPi based Logic Analyzer
Replies: 69
Views: 44870

Re: Panalyzer - a RaspberryPi based Logic Analyzer

I've had the kernel stopped at a breakpoint with interrupts disabled for at least 5-10 minutes at a time with no apparent problems. I agree with rgh that if something fails permanently just because you disabled interrupts for a few minutes then that would be a sign of a bug. And for any decent sampl...
by secretagent
Sun Jul 08, 2012 10:39 pm
Forum: Troubleshooting
Topic: operation in extreme environments
Replies: 15
Views: 2171

Re: operation in extreme environments

Note that there are some ambiguous regulations meant to prevent commercial GPS units from being used for missile guidance and so many units will not work properly at high altitudes. You may want to take a look at http://showcase.netins.net/web/wallio/GPSrcvrsvs60kft.htm for receivers that have been ...
by secretagent
Sat Jul 07, 2012 6:37 am
Forum: Automation, sensing and robotics
Topic: Panalyzer - a RaspberryPi based Logic Analyzer
Replies: 69
Views: 44870

Re: Panalyzer - a RaspberryPi based Logic Analyzer

The best performance would be achievable by running on the bare metal. Of course this would be much more complicated when it comes to saving the data (USB driver/stack or SD driver + file system). I guess the simplest and fastest way to do this would be a simple asm program (the bare metal kernel) ...
by secretagent
Sat Jun 30, 2012 4:32 am
Forum: Troubleshooting
Topic: 8000 interrupts per second when idle!
Replies: 141
Views: 44122

Re: 8000 interrupts per second when idle!

Can the Eth/USB system be turned back on after "bussuspend" without doing a full reboot, and if so how? The obvious 'echo 0 > /sys/devices/platform/bcm2708_usb/bussuspend' has no apparent effect- power draw remains 182 mA and no USB device can be mounted. One easy way is to compile dwc_otg as a mod...
by secretagent
Sat Jun 23, 2012 8:01 am
Forum: Troubleshooting
Topic: Kernel panic - not syncing: Fatal exception in interrupt
Replies: 44
Views: 17405

Re: Kernel panic - not syncing: Fatal exception in interrupt

Thanks dwilkin. It looks like more information will be required. If I give you a modified kernel that logs some debugging information from the USB driver to a file on the SD card will you be willing to run it and then send me the log file?
by secretagent
Thu Jun 21, 2012 6:32 am
Forum: General programming discussion
Topic: Trying to read the system timer
Replies: 8
Views: 2453

Re: Trying to read the system timer

The problem is that this defaults to type int*: volatile unsigned *syst; and when you do pointer arithmetic the address shifts by the specified amount times the size of the type. So, when you have SYST_CLO = 0x4 and syst + SYST_CLO, then the address is syst + 16 instead of syst + 4 and you end up wi...
by secretagent
Thu Jun 21, 2012 4:18 am
Forum: Automation, sensing and robotics
Topic: Panalyzer - a RaspberryPi based Logic Analyzer
Replies: 69
Views: 44870

Re: Panalyzer - a RaspberryPi based Logic Analyzer

There is another timer which can be made to run at up to 250 MHz and as far as I know is not used for anything else. It is described in chapter 14 of the datasheet. Here is some code I used for testing it: #include <linux/module.h> #include <linux/kernel.h> #include <mach/platform.h> #include <linux...
by secretagent
Fri Jun 15, 2012 4:54 am
Forum: Troubleshooting
Topic: Kernel panic - not syncing: Fatal exception in interrupt
Replies: 44
Views: 17405

Re: Kernel panic - not syncing: Fatal exception in interrupt

Yes, if anybody has access to the serial console (with a 3.3v to usb serial cable or a rs232 level shifter and a rs232 serial port) it would be the easiest way to get the stack trace in text form. If not, then a (good quality) picture may help too. kdump is technically ideal since it would capture t...
by secretagent
Wed Jun 13, 2012 6:09 pm
Forum: Troubleshooting
Topic: Kernel panic - not syncing: Fatal exception in interrupt
Replies: 44
Views: 17405

Re: Kernel panic - not syncing: Fatal exception in interrupt

Can somebody who has the problem with keyboards crashing the kernel post a stack trace and/or a usbmon dump?

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