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by davidmam
Sun Nov 25, 2012 7:38 pm
Forum: Scratch
Topic: Scratch controlling the real world with a RaspberryPi
Replies: 19
Views: 6776

Re: Scratch controlling the real world with a RaspberryPi

Thanks for your hard work on this. My son (10) tried Scratch with GPIO for the first time and loved it. He did most of the work once he had worked out what the various bits did.

Short video here:

http://www.flickr.com/photos/davidmam/8 ... hotostream
by davidmam
Sat Nov 24, 2012 12:52 am
Forum: Troubleshooting
Topic: USB redux
Replies: 514
Views: 203803

Re: USB redux

If I strip the code down to the bare minimum for talking to the USB device then the problem appears to disappear. Likewise if I call the usbreset code (which does a USBDEVFS_RESET call on the device) before initialising. That is an acceptable workround for now (I just have to wrap the lsusb/usbreset...
by davidmam
Fri Nov 23, 2012 4:12 pm
Forum: Troubleshooting
Topic: USB redux
Replies: 514
Views: 203803

Re: USB redux

Here is a link to the previous post. If you need more details then please let me know and I'll do what I can to help.

http://www.raspberrypi.org/phpBB3/viewt ... 20#p213220

This is with a fully updated raspbian.
by davidmam
Thu Nov 22, 2012 11:18 pm
Forum: Troubleshooting
Topic: USB redux
Replies: 514
Views: 203803

Re: USB redux

There is a reported and reproducible issue with USB where repeated device acquisition can hang the USB system. This is exemplified by libgphoto2 among others where one command executes perfectly but a subsequent one causes the system to hang. I can reproduce this at will with libusb-1.0 calls to a d...
by davidmam
Tue Nov 20, 2012 10:58 pm
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 271728

Re: USB - the Elephant in our Room

Is there any update on the issue with libusb where repeated acquisitions of a device fail? Ie you can send one request to a camera with gphoto2 but the second will hang the whole USB system, and the same I see with my data logger. Acquire once, fine, acquire twice (consecutively, not simultaneously)...
by davidmam
Fri Nov 16, 2012 3:46 pm
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 271728

Re: USB - the Elephant in our Room

OK, I reduced the timeout for the pyUSB calls from 1000 to 100ms and so far the Pi has stayed up for about 40 hours and is still going strong. My suspicions are that there is an issue in how libusb acquires devices with the dwc_otg module. I'll see if I can narrow this down with a minimal test scrip...
by davidmam
Thu Nov 15, 2012 10:00 am
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 271728

Re: USB - the Elephant in our Room

There is definitely an issue somewhere between libusb and the device. This is readily expemlified by gphoto2 where repeated calls to the device without resetting USB fail and hang the USB stack. I also experience this with libusb (via pyusb) talking to a device - first acquisition of the device is f...
by davidmam
Wed Nov 14, 2012 9:25 pm
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 271728

Re: USB - the Elephant in our Room

I noticed that the timeout on my python USB code was set to 1000ms which seems rather long. I've tried reducing that to 100ms and will see if that improves stability.

..d
by davidmam
Tue Nov 13, 2012 4:08 pm
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 271728

Re: USB - the Elephant in our Room

I tried removing the powered hub and plugging the TL-500 in directly. Locked up in about 2 hours. So today I just left it doing nothing, just booted up and on the network on wireless with nothing else plugged in. Not much use like that but see whether it falls over. If it does I'll try a different U...
by davidmam
Sun Nov 11, 2012 11:21 pm
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 271728

Re: USB - the Elephant in our Room

I still seem to be able to hang the Pi at will just by reading/writing to USB. See the 'capturing useful info thread'
by davidmam
Sun Nov 11, 2012 2:08 pm
Forum: Troubleshooting
Topic: USB issues - capturing useful information
Replies: 9
Views: 4071

Re: USB issues - capturing useful information

The latest fixes do not seem to have any effect on my issue. I am running a Pi connected to a wireless network and to an Arexx TL-500 datalogger via a powered hub. uname -a: Linux raspberrypi 3.2.27+ #260 PREEMPT Thu Nov 8 00:34:12 GMT 2012 armv6l Running Raspbian with all updates/upgrades. Include ...
by davidmam
Sat Nov 10, 2012 10:34 pm
Forum: Troubleshooting
Topic: USB issues - capturing useful information
Replies: 9
Views: 4071

Re: USB issues - capturing useful information

when were those latest updates? Unless they were within the last few days, they don't. Edit: OK, a newer version is available so I have updated. Time will tell.

..d
by davidmam
Fri Nov 09, 2012 8:31 pm
Forum: Troubleshooting
Topic: USB issues - capturing useful information
Replies: 9
Views: 4071

Re: USB issues - capturing useful information

So I have a headless Pi, it will lose network USB randomly about 12 -15 hours after I last logged in. What I am really looking for is something that I can do to capture that info when a crash occurs. Without USB and not being physically near the machine I can't use a keyboard or the network. HDMI do...
by davidmam
Fri Nov 09, 2012 7:13 pm
Forum: Troubleshooting
Topic: USB issues - capturing useful information
Replies: 9
Views: 4071

USB issues - capturing useful information

I, like others, am experiencing issues with USB on the Pi, leading to some frustration. Rather than posting yet another "It's not working" message, is there somewhere some guidelines to how to capture information that would actually be useful to those with the abilities to delve into the USB code? A...
by davidmam
Wed Nov 07, 2012 8:17 pm
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 271728

Re: USB - the Elephant in our Room

I tried the fix at github (issue 151) where you put 0x31 into the register when it says 0x30 This didn't stop things dying after about 18 hours. Syslog reads: Nov 7 16:13:38 raspberrypi kernel: [73638.092377] ieee80211 phy0: wlan0: No probe r sponse from AP 74:44:01:69:6c:05 after 500ms, disconnecti...
by davidmam
Mon Nov 05, 2012 6:35 pm
Forum: Troubleshooting
Topic: USB - the Elephant in our Room
Replies: 802
Views: 271728

Re: USB - the Elephant in our Room

I have ben suffering the same sort of USB issues. I'm attempting to capture data from an Arexx tl-500 data logger and, via some custom code goodness, combine the data with some one-wire net data and upload to COSM. After a while the USB decides to drop off the system rendering it inaccessibe via net...
by davidmam
Fri Nov 02, 2012 2:30 pm
Forum: Troubleshooting
Topic: USB/network failure
Replies: 7
Views: 950

Re: USB/network failure

It all seems happy - cheap cable with obviously too high a resistance.
I get the Pi to a state I like then take an image of the SD card to save having to go through all the setup again.

..d
by davidmam
Thu Nov 01, 2012 10:42 pm
Forum: Troubleshooting
Topic: USB/network failure
Replies: 7
Views: 950

Re: USB/network failure

OK, My bad. I had inadvertently used a different microUSB lead (a very cheap one) and that was the issue.

The power supply issue really is something that needs addressing to be more consistent rather than abusing an existing standard.
by davidmam
Thu Nov 01, 2012 10:17 pm
Forum: Troubleshooting
Topic: USB/network failure
Replies: 7
Views: 950

Re: USB/network failure

I get no response from the keyboard so logging in and running commands is a non-starter.
Likewise no response from the network.
by davidmam
Thu Nov 01, 2012 7:33 pm
Forum: Troubleshooting
Topic: USB/network failure
Replies: 7
Views: 950

USB/network failure

I have the Raspbian image (the latest prior to the 512Mb update). I've been running the Pi fine for a while but never more than for a few hours. I have been trying to get a particular project running (temperature logging via an Arex tl-500) but run into a problem. The Pi would randomly freeze - just...
by davidmam
Sun Sep 30, 2012 2:34 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: kernel patch for Dallas 1-wire interface
Replies: 227
Views: 156333

Re: kernel patch for Dallas 1-wire interface

Are the wee PCBs with the dual RJ45 sockets on your own design or are they available somewhere? They look kind of just what I need for a project.. I'm not sure what the rules on advertising are here so mods please let me know if I'm being naughty here... They are my design, I run a small home busin...
by davidmam
Fri Sep 28, 2012 5:05 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: kernel patch for Dallas 1-wire interface
Replies: 227
Views: 156333

Re: kernel patch for Dallas 1-wire interface

Are the wee PCBs with the dual RJ45 sockets on your own design or are they available somewhere?
They look kind of just what I need for a project..
by davidmam
Mon Aug 20, 2012 8:40 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: kernel patch for Dallas 1-wire interface
Replies: 227
Views: 156333

Re: kernel patch for Dallas 1-wire interface

The wiringPi library privides a nice command line interface to the GPIO port - well worth looking at.
by davidmam
Sun Aug 19, 2012 10:23 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Need help to get a Rotary Encoder working
Replies: 16
Views: 9663

Re: Need help to get a Rotary Encoder working

I've doen something similar on arduino where I use a simple binary counter to sample the pulses (in my case it is a magnet on a drum passing a hall effect sensor). The counter is then read via a PISO. This requires that you poll at least once every full cycle of the counter and that you don't need t...
by davidmam
Sun Aug 19, 2012 3:39 pm
Forum: Other projects
Topic: Photography Projects
Replies: 150
Views: 66640

Re: Photography Projects

you should be able to set the filename as --filename 'test-%y%m%d-%H%M%S.jpg'

which will give you a timestamp.

Don't know how to skip the initialising - it is a bit of a pain having that lag.

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