Go to advanced search

by PiGraham
Thu Mar 13, 2014 6:41 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: [Announcement] New USB chip-solution
Replies: 12
Views: 2369

Re: [Announcement] New USB chip-solution

Presumably those are multi-function pins, since the chip only has 28 pins.
It looks like a neat little board. Is it controlled via a virtual serial port on USB?
by PiGraham
Thu Mar 13, 2014 6:19 pm
Forum: Other projects
Topic: Pi in high magnetic fields
Replies: 42
Views: 7231

Re: Pi in high magnetic fields

7 Tesla is a 'helluvalot'. I'm not surprised something fails. It not something the Raspi was designed to withstand! I'm with the poster above - probably the magnetics in the ethernet connector, although the electrons in the chip will be all over the place. Do you work at CERN on the LHC? That's the...
by PiGraham
Thu Mar 13, 2014 5:43 pm
Forum: Troubleshooting
Topic: HDMI to VGA
Replies: 3
Views: 418

Re: HDMI to VGA

I just bought one of these from CPC (under a tenner):

Image

Link

Works with my Pi and AOC monitor.
by PiGraham
Thu Mar 13, 2014 5:37 pm
Forum: Other projects
Topic: Pi in high magnetic fields
Replies: 42
Views: 7231

Re: Pi in high magnetic fields

This is a static 7T field, yes?
Ethernet uses magnetic isolators. Could they be saturating the the strong field?
Could you put the Pi in a magnetically screened enclosure?
Perhaps the magnetics can be replaced with opto-isolators.
by PiGraham
Thu Mar 13, 2014 4:38 pm
Forum: Automation, sensing and robotics
Topic: Raspberry Pi - How to control motors...
Replies: 48
Views: 27482

Re: Raspberry Pi - How to control motors...

Hey Guys, So I have been successfully controlling two DC motors through the L298N H-Bridge, until recently. Right from the start, I noticed that my Pi's SOC (to be honest, the whole board itself) was getting very hot. And when I say hot, I mean when you touch the board, you only can keep it there f...
by PiGraham
Thu Mar 13, 2014 4:31 pm
Forum: General discussion
Topic: RPi
Replies: 4
Views: 409

Re: RPi

Quick Start (Link at the top of the page!)
by PiGraham
Thu Mar 13, 2014 4:28 pm
Forum: Automation, sensing and robotics
Topic: Home automation developer
Replies: 6
Views: 1132

Re: Home automation developer

Home automation is a popular use for RasPi.
See?
by PiGraham
Wed Mar 12, 2014 9:06 pm
Forum: Beginners
Topic: Combining Microphone input and Raspberry Cam - FFMPEG
Replies: 5
Views: 1609

Re: Combining Microphone input and Raspberry Cam - FFMPEG

The Wolfson card isn't cheap compared to EBay USB sound cards, but it does have a pair of MEMS microphones on board that sound pretty good. It also has a stereo speaker amp on there that will directly drive speakers. Volume won't rock the house, but it is fine for casual listening in fairly quiet co...
by PiGraham
Wed Mar 12, 2014 6:16 pm
Forum: Beginners
Topic: Intern time keeping
Replies: 19
Views: 2165

Re: Intern time keeping

TBH I though Raspbian had fake-hwclock set-up out of the box The OP said that they are running RaspBMC. I don't know if that has fakehwclock installed. Opps, I missed that bit at the end. Maybe RaspBMC doesn't run fake-hwclock. Don't know. Even so, once set the system clock should keep running as l...
by PiGraham
Wed Mar 12, 2014 5:41 pm
Forum: Python
Topic: Edge Detection
Replies: 1
Views: 1350

Re: Edge Detection

Code: Select all

GPIO.add_event_detect(12, GPIO.BOTH, callback=forward, bouncetime=300)
Then test the input in the callback to see if was rising or falling.
by PiGraham
Wed Mar 12, 2014 5:14 pm
Forum: Beginners
Topic: Combining Microphone input and Raspberry Cam - FFMPEG
Replies: 5
Views: 1609

Re: Combining Microphone input and Raspberry Cam - FFMPEG

This might help.
https://github.com/iizukanao/picam
I'm in the process of compiling stuff to try it out with a Wolfson card (uses ALSA).
by PiGraham
Wed Mar 12, 2014 4:58 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Rpi cameras
Replies: 11
Views: 1754

Re: Rpi cameras

Note that you may not be able to stream video from two USB webcams at once.
by PiGraham
Wed Mar 12, 2014 4:55 pm
Forum: Beginners
Topic: Intern time keeping
Replies: 19
Views: 2165

Re: Intern time keeping

Hi all, i have an issue with the system clock. I know that the RaspPI has no RTC and therefor syncs it's time with ntp. This all runs fine. Having a correct time and then disconnecting the internet, the PI ends up with resetting it's time once to 01:00:00 and counting on from there. My question her...
by PiGraham
Wed Mar 12, 2014 8:44 am
Forum: Beginners
Topic: Raspbmc + GPIO
Replies: 5
Views: 939

Re: Raspbmc + GPIO

Try this: Go to Power icon >> Exit, Press ESC when Prompted to go to a shell Then you should be able to do most things from there. Raspbmc does not have X installed, so no x-windows GUI (no Scratch, no IDLE), but you can control GPIO, compile c code, run Python scripts etc. XBMC supports add-ons for...
by PiGraham
Tue Mar 11, 2014 12:41 pm
Forum: Troubleshooting
Topic: Sync GPIO pulse to internal time: why so difficult?
Replies: 7
Views: 1752

Re: Sync GPIO pulse to internal time: why so difficult?

Use Joan's pigpio solution.
by PiGraham
Tue Mar 11, 2014 10:40 am
Forum: Troubleshooting
Topic: Sync GPIO pulse to internal time: why so difficult?
Replies: 7
Views: 1752

Re: Sync GPIO pulse to internal time: why so difficult?

Do you want a pulse each second of real time, synchronised to the soft clock? Depending on what you are trying to do you probably need an RTC or other hardware time reference. GPS receivers have an accurate clock. Some will output a pulse once per second. What accuracy / synchronisation do you need?...
by PiGraham
Tue Mar 11, 2014 7:39 am
Forum: Graphics, sound and multimedia
Topic: Q about video process
Replies: 1
Views: 447

Re: Q about video process

Video streaming is no problem, but real-time video analysis depends on your application, and your definition of real-time.
CPU-intensive operations are limited by the relatively slow CPU.
by PiGraham
Tue Mar 11, 2014 7:08 am
Forum: Beginners
Topic: is raspberry pi capable of doing this?
Replies: 4
Views: 876

Re: is raspberry pi capable of doing this?

one xbmc is a good choice for you. It runs dlna server and a web remote server for remote access to content and remote control.

I run xbmc on an android tv stick and smartphone and pc control is good.
by PiGraham
Mon Mar 10, 2014 9:27 pm
Forum: Automation, sensing and robotics
Topic: Help with a timing circuit
Replies: 6
Views: 786

Re: Help with a timing circuit

how do the objects travel from one machine to the other? you may want to consider writing a shift register delay clocked by an encoder. this works well with conveyor belts.
by PiGraham
Mon Mar 10, 2014 6:26 pm
Forum: General discussion
Topic: cctv interfacing to raspberri pi.
Replies: 27
Views: 4652

Re: cctv interfacing to raspberri pi.

Dear PiGraham... i am having UVC of easycap DC60 bt it requires drivers for linux..n m not having it... can me provide me drivers for EASYCAP DC 60 UVC?? Easycap devices are not UVC. According to the info I posted UVC devices do not require specific drivers. Does Raspbian have UVC support built in?...
by PiGraham
Mon Mar 10, 2014 8:56 am
Forum: General discussion
Topic: cctv interfacing to raspberri pi.
Replies: 27
Views: 4652

Re: cctv interfacing to raspberri pi.

I purchased a UVC compatible video capture device that works great with the Raspberry Pi. I'm able to plug in my composite video source (camera) into it, then plug it into the USB port, and capture and stream the video using mjpg_streamer. Works great! $70 USD for FEBON 100 UVC video grabber from A...
by PiGraham
Fri Mar 07, 2014 8:32 pm
Forum: Camera board
Topic: picamera and usb mic.. How?!
Replies: 2
Views: 2129

Re: picamera and usb mic.. How?!

You can record audio with arecord, part of alsa-utils.
However, I assume you would probably like to record audio and video synchronised in one video file. I don't know of solution for that.
by PiGraham
Fri Mar 07, 2014 3:04 pm
Forum: General discussion
Topic: Small screen options for beginner
Replies: 2
Views: 1661

Re: Small screen options for beginner

You could try asking over at sparkfun.com, adafruit.com and similar companies that make LCD 'shields' for micro controllers. They may have an interface from SPI to LCD. I don't know if they have anything for a blackberry screen. Forum user Texy has designed an interface for a 2.8" TFT and it works v...
by PiGraham
Fri Mar 07, 2014 9:33 am
Forum: Python
Topic: Execute 2 tasks in parallel (one task depends on the other)
Replies: 3
Views: 992

Re: Execute 2 tasks in parallel (one task depends on the oth

Hi, let's suppose I have two functions: def getTemperature(): # prints a temperature every minute def turnOnLED(): # turns on a LED for 10min then turns it off ... getTemperature() stops printing its values till the LED is turned off.]/quote] The trick is to not use 'busy waits' (e.g. Sleep() or wh...
by PiGraham
Thu Mar 06, 2014 2:07 pm
Forum: General discussion
Topic: Year 13 School Project
Replies: 1
Views: 307

Re: Year 13 School Project

I suggest you take a look at PiHAT - http://www.raspberrypi.org/phpBB3/viewtopic.php?f=37&t=26485&p=495352&hilit=home+automation+433mhz#p495352 https://github.com/s7mx1/pihat Get some Status remote control power plugs and control one by radio signal from the Pi. This means you don't have to touch da...

Go to advanced search