Go to advanced search

by Douglas6
Sun Dec 15, 2013 5:55 pm
Forum: Troubleshooting
Topic: Bluetooth Dongle not detected by hcitool
Replies: 20
Views: 56686

Re: Bluetooth Dongle not detected by hcitool

Douglas8 I got promoted :) I'm shooting in the dark here (obviously), but you might try moving that entire directory away and rebooting. Maybe some cache is not happy with the new distro. DId Bluez get upgraded? dpkg --status bluez | grep '^Version:' Version: 4.99-2 I have to run out and do family ...
by Douglas6
Sun Dec 15, 2013 5:26 pm
Forum: Troubleshooting
Topic: Bluetooth Dongle not detected by hcitool
Replies: 20
Views: 56686

Re: Bluetooth Dongle not detected by hcitool

It does sound like a problem with the class. It might be interesting to see what's in your /var/lib/bluetooth/<xx:xx:xx:xx:xx:xx>/config file. Mine (working, also a CSR dongle) looks like this: cat /var/lib/bluetooth/00\:15\:83\:0C\:BF\:EB/config name raspberrypi-0 pairable yes class 0x420100 onmode...
by Douglas6
Sun Dec 15, 2013 5:04 pm
Forum: Troubleshooting
Topic: Bluetooth Dongle not detected by hcitool
Replies: 20
Views: 56686

Re: Bluetooth Dongle not detected by hcitool

Well, that would explain why it wasn't brought up automatically. I'll see if if I can reproduce the issue tonight. Are you running Raspian, and this occurred after an apt-get upgrade?
by Douglas6
Sun Dec 15, 2013 4:21 pm
Forum: Troubleshooting
Topic: Bluetooth Dongle not detected by hcitool
Replies: 20
Views: 56686

Re: Bluetooth Dongle not detected by hcitool

Normally the adapter is brought up at boot, but yours is down as shown by the hciconfig results. Do this:

Code: Select all

sudo hciconfig hci0 up
hcitool dev
and see if that persists a reboot. To make it discoverable:

Code: Select all

hciconfig hci0 piscan 
Or 'noscan' to make it undiscoverable.
by Douglas6
Fri Dec 13, 2013 7:25 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Too many switches, too low voltage?
Replies: 3
Views: 1153

Re: Too many switches, too low voltage?

"The maximum permitted current draw from the 3.3 V pins is 50 mA."
http://elinux.org/RPi_Low-level_peripherals#Power_pins
by Douglas6
Fri Dec 13, 2013 3:13 pm
Forum: Java
Topic: Real time GPIO monitoring with Pi4J [SOLVED: use pigpio]
Replies: 8
Views: 10764

Re: Best way to achieve time precision on GPIO interrupts

Java, with its garbage collection, is probably particularly bad at this sort of thing.
by Douglas6
Fri Dec 13, 2013 2:58 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Level-shifters for the pi
Replies: 8
Views: 2662

Re: Level-shifters for the pi

The third method is to use a transistor buffer, such as the one shown on the right hand side of this image: https://tylerjones.me/wp-content/uploads//2012/11/npn-arduino-rpi-buffer.jpg And if I want to pull a pin low, do I just move (and replace Vcc) the RX pin to the collector? Keep both resistors?
by Douglas6
Fri Dec 13, 2013 5:16 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: GPIO Pin Tester?
Replies: 10
Views: 24816

Re: GPIO Pin Tester?

Perfect. Easy-peasy, thanks!
by Douglas6
Thu Dec 12, 2013 9:10 pm
Forum: Networking and servers
Topic: Bluetooth Access Point
Replies: 56
Views: 43556

Re: Bluetooth Access Point

I'm sure that tutorial wasn't too complicated once you have the python-dbus working correctly. It's not really. Using wlan0 instead of eth0 is a bit different, and also when using Raspian, you'll need to 'sudo apt-get install bridge-utils' yourself. And here's another tip that would have saved me 3...
by Douglas6
Thu Dec 12, 2013 6:52 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: GPIO Pin Tester?
Replies: 10
Views: 24816

Re: GPIO Pin Tester?

Thanks everybody! @Dougie, thanks for the pointer to the wiringPi pintest script; that looks like the easiest way to test GPIO inputs. For outputs, it looks like I need to take some measurements. Just to be clear, if the multimeter reads 3.3V-ish, I can be confident that the output driver is un-comp...
by Douglas6
Thu Dec 12, 2013 4:53 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: GPIO Pin Tester?
Replies: 10
Views: 24816

GPIO Pin Tester?

My IR transmitter circuit (home-built, self-designed) has stopped working reliably, and I'm afraid I've singed a pin. My only surprise is that I've not managed to fry an entire Pi with my electronic stumbling about. My question involves the best way to test the GPIO pins to try and find any damaged ...
by Douglas6
Wed Dec 11, 2013 9:58 pm
Forum: Beginners
Topic: IP Address
Replies: 2
Views: 565

Re: IP Address

XBMC will show the IP address on the System | System info | Summary tab.
by Douglas6
Wed Dec 11, 2013 2:46 am
Forum: Python
Topic: run a function every x min
Replies: 21
Views: 7753

Re: run a function every x min

Check your indentation on the two lines after # restart the timer. Python is very picky about indentation. You're starting the timer twice, and never restarting it.

Then the program enters your infinite loop where it does nothing.
by Douglas6
Tue Dec 10, 2013 2:42 am
Forum: Networking and servers
Topic: Bluetooth Access Point
Replies: 56
Views: 43556

Re: Bluetooth Access Point

After catching a second wind and attacking this again, I think I licked it. In fact I'm typing this on my phone, connected via Bluetooth to a Raspberry Pi access point connected via WiFi to my router and out over the internet. It's a bit of an awkward process but it works.Gonna see if I can automate...
by Douglas6
Mon Dec 09, 2013 9:36 pm
Forum: Off topic discussion
Topic: 8-bit pranks
Replies: 5
Views: 3867

Re: 8-bit pranks

In High School (late '70s), I managed to hack into the HP 2000/Access time sharing system we used, and wrote a system-level program that required a password for log on. I still remember the password I hard-coded in: "ennui". Unfortunately, my program converted user input to uppercase before comparin...
by Douglas6
Mon Dec 09, 2013 1:05 pm
Forum: Off topic discussion
Topic: Good music to write code?
Replies: 14
Views: 5249

Re: Good music to write code?

I read somewhere that listening to music occupies a creative part of the brain that could otherwise be spent on solving coding problems.

The study did not include the effects of spouses.
by Douglas6
Mon Dec 09, 2013 12:47 pm
Forum: Other programming languages
Topic: Bash script - LCD Screen - Without Python
Replies: 10
Views: 5794

Re: Bash script - LCD Screen - Without Python

If you don't like Python, I've got a Java class for that device :)
by Douglas6
Sun Dec 08, 2013 6:08 pm
Forum: Automation, sensing and robotics
Topic: DHT22 humidity sensor stops working
Replies: 11
Views: 10547

Re: DHT22 humidity sensor stops working

RogueBarbarian wrote:Got mine from Adafruit and no way to provide feedback there.
http://forums.adafruit.com
by Douglas6
Sun Dec 08, 2013 4:50 pm
Forum: Python
Topic: Recalling a thread when thread complete
Replies: 14
Views: 2442

Re: Recalling a thread when thread complete

Joan's suggestion might be easier in this case; if your thread has a sleep in the loop, it gives the main code time (cycles) to do the display refresh. However, I'm thinking you may see the same results. Threading on a single processor system is really just a convenience for the programmer; the CPU ...
by Douglas6
Sat Dec 07, 2013 9:24 pm
Forum: Networking and servers
Topic: Bluetooth Access Point
Replies: 56
Views: 43556

Re: Bluetooth Access Point

I decided to give this a try, as I thought it would be a good learning experience. It is, but I clearly have a lot more to learn, as I could not get the reverse tethering over bluetooth to work. But I WAS able to get the test-nap.py program to run, using Python 2.7 as included with the latest Raspia...
by Douglas6
Thu Dec 05, 2013 10:49 pm
Forum: Networking and servers
Topic: Bluetooth Access Point
Replies: 56
Views: 43556

Re: Bluetooth Access Point

I used the debugger in the same Idle 3 to test run the 'test-nap' script and it fell over at the same line attempting the import dbus. Probably a daft question but I assume there is no need to include a "path" statement anywhere to tell the script where to find dbus? http://www.raspberrypi.org/phpB...
by Douglas6
Thu Dec 05, 2013 6:19 pm
Forum: Beginners
Topic: Incoming connections GPIO
Replies: 8
Views: 1010

Re: Incoming connections GPIO

Adafruit has a tutorial and Python module that makes it really easy to wire up and talk to an MCP23017:

http://learn.adafruit.com/mcp230xx-gpio ... spberry-pi
by Douglas6
Thu Dec 05, 2013 4:36 pm
Forum: Python
Topic: run a function every x min
Replies: 21
Views: 7753

Re: run a function every x min

Simpler is better. If you need just one timer, use just one timer.
by Douglas6
Thu Dec 05, 2013 12:10 am
Forum: Python
Topic: run a function every x min
Replies: 21
Views: 7753

Re: run a function every x min

It depends on what you want to happen. If you want to call another function that also runs every five minutes, immediately after the first one, then yes, just call it in the same timer thread call-back function (stopAndDoThis). If you need to run it on a different schedule, say, every 12 minutes, TH...
by Douglas6
Wed Dec 04, 2013 3:04 am
Forum: Python
Topic: run a function every x min
Replies: 21
Views: 7753

Re: run a function every x min

No. The Timer makes use of a very useful feature of an OS like Linux called 'multi-threading". This means your code can continue running while another process, your timer, runs (roughly) in parallel. Your timer counts down until it is ready to run, does its thing, and then can start over, all by its...

Go to advanced search