Go to advanced search

by richardp
Sun Apr 28, 2013 10:27 am
Forum: Off topic discussion
Topic: "Big brother to switch off your fridge"
Replies: 64
Views: 7230

Re: "Big brother to switch off your fridge"

@Rene_is_I As you noted, alot of the boilers have been rewired; and it will be the same scenario with the 'Smart' chips.. one snipped track, a low-pass filter to clean out frequencies that are not 50Hz (in the case of PowerLine Comms) are all options.. where there is a big brother, there is a little...
by richardp
Sun Apr 28, 2013 9:21 am
Forum: Off topic discussion
Topic: "Big brother to switch off your fridge"
Replies: 64
Views: 7230

Re: "Big brother to switch off your fridge"

This has been going on for years already ... Geysers/Boilers in many countries are on ripple switches. and are switched off at peak hours. Bantering the word 'Smart' just gives it some sales pitch... I remember when the term 'Fuzzy Logic' was used to sell stuff.
by richardp
Sun Apr 28, 2013 8:17 am
Forum: Raspbian
Topic: Audio intercom/repeater - PulseAudio
Replies: 0
Views: 986

Audio intercom/repeater - PulseAudio

Hi All, Some background - I am using a Pi as a audio repeater/Intercom system. The application is for a motorbike intercom that can be interfaced to a mobile phone and an ipod. Operation : What comes in one microphone source, gets repeated to ALL earpieces. For this I am using the pulseaudio system ...
by richardp
Wed Apr 17, 2013 10:03 am
Forum: General discussion
Topic: Please add hardware/GPU encryption
Replies: 23
Views: 10877

Re: Please add hardware/GPU encryption

So there is a hardware P-RNG (I dont believe its a true RNG), and a SHA256 piece of silicon, but there is no AES/DES/RSA silicon?... I really find that exceptionally hard to believe, as the RNG is the start of all the Crypto and SHA is pretty much a non starter if not used in the context of a crypto...
by richardp
Sat Mar 23, 2013 12:44 pm
Forum: Automation, sensing and robotics
Topic: Open Collector the same as GPIO?
Replies: 3
Views: 1207

Re: Open Collector the same as GPIO?

Why not solder header pins on the Sparkfun board to extend the Raspi headers? should be quite easy to do.

Richard
by richardp
Sat Mar 23, 2013 12:18 pm
Forum: Automation, sensing and robotics
Topic: Open Collector the same as GPIO?
Replies: 3
Views: 1207

Re: Open Collector the same as GPIO?

Open collector is a output configuration.. not really an GPIO, more like a GPO (not input). OpenCollector are typically used to drive higher current load outputs/isolate from the sensitive Raspberry GPIO lines, so if you find the corresponding input pin for the output on the Sparkfun board, it will ...
by richardp
Fri Mar 08, 2013 8:00 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: GPIO Interrupt / Max interrupt freq
Replies: 0
Views: 425

GPIO Interrupt / Max interrupt freq

Hi All, Does anyone know the maximum speed the interrupts can run at on the RPi ? All I want to do is snapshot the GPIO line states when a Sync line goes low, and there is a clock pulse (Sample on Clock) The speeds I am looking at are about 25Mhz .. anyone think the Pi can do this ? (a Cheap-mans lo...
by richardp
Wed Mar 06, 2013 9:08 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Will the raspi understand the output of this ADC?
Replies: 7
Views: 1395

Re: Wil the raspi understand the output of this ADC?

@richardp: Originally, I wanted to do precise time domain measurements, as I thought of using the Pi as a sound level meter. After some investigation, I found I2S would be the ideal protocol, as it was audio oriented, and allowed for [email protected] sampling. But reading I2S data has yet to be impleme...
by richardp
Wed Mar 06, 2013 8:22 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Will the raspi understand the output of this ADC?
Replies: 7
Views: 1395

Re: Wil the raspi understand the output of this ADC?

Depends on your application...

I would rate them much the same for connectivity... for speed I would use SPI, for a slower multi-drop bus then I2C.

How many samples/second do you want to do?
by richardp
Wed Mar 06, 2013 7:37 am
Forum: Troubleshooting
Topic: USB redux
Replies: 514
Views: 199066

Re: USB redux

Any updates? 3 weeks since last post, is the USB still a thorny issue?
by richardp
Tue Mar 05, 2013 7:16 pm
Forum: Automation, sensing and robotics
Topic: Detecting mains voltage
Replies: 29
Views: 11103

Re: Detecting mains voltage

As one other Pi-romaiac done.. Dismantled an AC detection pen and interfaced it to a Pi

http://www.ebay.co.uk/itm/AC-Electric-V ... 5d3b3fbc8f
by richardp
Sun Feb 24, 2013 9:08 am
Forum: Automation, sensing and robotics
Topic: Detecting mains on/off
Replies: 8
Views: 1492

Re: Detecting mains on/off

Why make things difficult when a Pilot relay will do... :lol:
by richardp
Thu Feb 14, 2013 5:03 pm
Forum: Python
Topic: General inter-process communication in python
Replies: 7
Views: 6934

Re: General inter-process communication in python

D-BUS .. thats the flavour of the day for my IPC processes.

Its already there. There is no right/wrong way to achieve your task, its what you feel comfortable doing.

R
by richardp
Wed Feb 13, 2013 8:09 am
Forum: Troubleshooting
Topic: USB microphone not playing nice
Replies: 5
Views: 2485

Re: USB microphone not playing nice

Hi there, I get good audio using the USB 1.1 cmdline.txt on a Raspi v0 (256MB), Powered USB hub and some cheap USB sound adapters (*Caveat!) echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor - Using the latest Debian that Hexxeh has avaliable. Linux raspberrypi 3.6.11+ #371 PR...
by richardp
Tue Feb 12, 2013 9:18 pm
Forum: Graphics, sound and multimedia
Topic: RPi and real-time, low-latency audio
Replies: 189
Views: 75889

Re: RPi and real-time, low-latency audio

Nice writeup. I am attempting a similar thing using Gstreamer/ALSA (low latency, not synth) - It works, but not for any length of time. After about 5 minutes USB Audio output stops. My end goal is to make a motorbike intercom using commodity devices, and I want a Pi to be part of it :D gst-launch -v...
by richardp
Tue Feb 12, 2013 5:29 pm
Forum: Troubleshooting
Topic: USB redux
Replies: 514
Views: 199066

Re: USB redux

Any light at the end of the USB tunnel?.... the USB performance/data loss scuppers my projects completely.

R
by richardp
Thu Jan 10, 2013 1:43 pm
Forum: Off topic discussion
Topic: Cubieboard vs RaspberryPi B
Replies: 73
Views: 54179

Re: Cubieboard vs RaspberryPi B

Found this relatively interesting board in rpi price range. Official site: http://cubieboard.org/ They sold small numbers last month and are now trying to fund a 1k+ run via indiegogo: http://www.indiegogo.com/cubieboard Some difference highlights from specs: 1G ARMv7 cortex-A8 processor (2x as fas...
by richardp
Thu Jan 10, 2013 11:53 am
Forum: Off topic discussion
Topic: Cubieboard vs RaspberryPi B
Replies: 73
Views: 54179

Re: Cubieboard vs RaspberryPi B

Found this relatively interesting board in rpi price range. Official site: http://cubieboard.org/ They sold small numbers last month and are now trying to fund a 1k+ run via indiegogo: http://www.indiegogo.com/cubieboard Some difference highlights from specs: 1G ARMv7 cortex-A8 processor (2x as fas...
by richardp
Tue Jan 08, 2013 8:43 pm
Forum: Other projects
Topic: Race vehicle data logger.
Replies: 48
Views: 43989

Re: Race vehicle data logger.

I built a non-pi and non race datalogger using a cheap £0 ELM327 based bluetooth system http://www.ebay.co.uk/itm/ELM327-Bluetooth-ODBII-OBD2-OBD-2-OBDII-Scanner-Reader-Auto-Car-Diagnostic-Tool-/320939015574?pt=UK_Diagnostic_Tools_Equipment&hash=item4ab974bd96 Software was PyODB http://www.obdtester...
by richardp
Tue Jan 08, 2013 10:11 am
Forum: Graphics, sound and multimedia
Topic: QtMultimedia, OpenMAX and GStreamer - will it ever work?
Replies: 19
Views: 14799

Re: QtMultimedia, OpenMAX and GStreamer - will it ever work?

The December raspian, gstreamer and OpenMax dont work.. Since QT uses gstreamer, rather look there.

GSTOMX stops processing at a point. I am still trying to find out what changed and why.
by richardp
Sun Jan 06, 2013 4:37 pm
Forum: Troubleshooting
Topic: SD Card reader...Rookie error
Replies: 2
Views: 520

Re: SD Card reader...Rookie error

Just spent a few frusting hours trying to flash a pi operating image to my SDHC card. Kept getting i/o errors. Sit back, drink coffee and think about it. Then realised that my card reader is quite old and a quick check showed it was an SD, as opposed to a SDHC reader!! whoops! A quick visit to the ...
by richardp
Sun Jan 06, 2013 2:32 pm
Forum: Graphics, sound and multimedia
Topic: gst-omx issue or recent change to openmax issue?
Replies: 15
Views: 9309

Re: gst-omx issue or recent change to openmax issue?

Arrrrrrrgh... examples I made 6 months ago are now non-functional on the Pi Linux raspberrypi 3.2.27+ #1 PREEMPT Sat Dec 29 16:54:58 GMT 2012 armv6l GNU/Linux using the codebase (is this correct?) git clone git://anongit.freedesktop.org/gstreamer/gst-omx -b raspberry GST_DEBUG="omx:5" gst-launch-0.1...
by richardp
Sat Jan 05, 2013 7:24 pm
Forum: OpenMAX
Topic: omxtx - open source transcoding example
Replies: 239
Views: 127149

Re: omxtx - open source transcoding example

Nope... I download a new H264 stream (Simpsons trailer) - verified there are 2 streams. wget http://downloads.dvdloc8.com/trailers/divxdigest/simpsons_movie_trailer.zip No Audio but video in VLC .. mplayer plays too fast R Can you perhaps share the first 10Megs of your sample stream (should be a cou...
by richardp
Sat Jan 05, 2013 5:58 pm
Forum: OpenMAX
Topic: omxtx - open source transcoding example
Replies: 239
Views: 127149

Re: omxtx - open source transcoding example

There are 3 streams in the file.... so I think stream 1 is throwing the encoder off course. I will generate files that are 1Video+1Audio and perhaps subtitles. The Invalid timebase comes from stream 1 (st:1 in the error I assume) Richard Input: Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'out.mov': Meta...
by richardp
Sat Jan 05, 2013 5:13 pm
Forum: OpenMAX
Topic: omxtx - open source transcoding example
Replies: 239
Views: 127149

Re: omxtx - open source transcoding example

Oops. Uninitialised bsfc in dofiltertest() being returned unset. Fixed. Thanks... that solved the Segfault Just noticed... Invalid timebase when encoding the original.mov Output: Output #0, mov, to 'out.mov': Stream #0.0: Video: libx264, yuv420p, 854x480, q=-1--1, 2097 kb/s, 24 fps, 24 tbr, 2400 tb...

Go to advanced search