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by dgordon42
Sat Jun 17, 2017 11:28 am
Forum: Troubleshooting
Topic: Pi 3B UART limited to 9 chars?
Replies: 17
Views: 3464

Re: Pi 3B UART limited to 9 chars?

I'll wait until I hear the kernel has been updated with the fix - will that notice come here or at the github site? There would normally be a posting on Github about any progress, and then someone will most likely update this thread. I guess you were just unlucky, the 4.9 kernel must just have been...
by dgordon42
Fri Jun 16, 2017 6:39 pm
Forum: Raspbian
Topic: wheezy & jessie give different result for "who -b" boot date
Replies: 5
Views: 866

Re: wheezy & jessie give different result for "who -b" boot

MrCobol wrote:Is it a bug ? or my error?
It's a bug in Jessie/SystemD.
The 'last' command also incorrectly reports the boot up time as 01 Jan 1970, the Linux epoch.
Use Dougie's suggested commands instead.

Dave.
by dgordon42
Fri Jun 16, 2017 6:04 pm
Forum: Troubleshooting
Topic: Pi 3B UART limited to 9 chars?
Replies: 17
Views: 3464

Re: Pi 3B UART limited to 9 chars?

See @jdb's post above. You are running the 4.9 kernel, and it's got a bug in it! I upgraded from the 4.4 to the 4.9 today, and now I can reproduce your problem. The RPi guys are looking at it. They are usually pretty good at fixing these things, just have to wait for a bit. The rest of your setting ...
by dgordon42
Fri Jun 16, 2017 12:42 pm
Forum: Troubleshooting
Topic: Pi 3B UART limited to 9 chars?
Replies: 17
Views: 3464

Re: Pi 3B UART limited to 9 chars?

jdb wrote:An issue has been opened on Github: https://github.com/raspberrypi/linux/issues/1855 . PhilE is looking at it.
Thanks for the reply, I've just upgraded to the 4.9.24 kernel and am now seeing the same problem on the ttyS0 UART.
The ttyAMA0 UART is working normally.

Dave.
by dgordon42
Fri Jun 16, 2017 11:44 am
Forum: Troubleshooting
Topic: Pi 3B UART limited to 9 chars?
Replies: 17
Views: 3464

Re: Pi 3B UART limited to 9 chars?

You are right - it is really strange.

Just so I can see how your Pi is set up, can you post the output of the following commands:

Code: Select all

uname -a
cat /boot/cmdline.txt
grep -v -e \# /boot/config.txt
Thanks,
Dave.
by dgordon42
Wed Jun 14, 2017 4:30 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: set constant I2C frequency on Raspberry Pi3
Replies: 3
Views: 1157

Re: set constant I2C frequency on Raspberry Pi3

I would have expected

Code: Select all

core_freq=250
dtparam=i2c_arm_baudrate=100000
in '/boot/config.txt' to set up a stable 100kHz i2c clock, but I have no way of checking or measuring it here.

Any changes to '/boot/config.txt' require a reboot to take effect.

Dave.
by dgordon42
Fri Jun 09, 2017 7:49 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: set constant I2C frequency on Raspberry Pi3
Replies: 3
Views: 1157

Re: set constant I2C frequency on Raspberry Pi3

Adding:

Code: Select all

core_freq=250
to the '/boot/config.txt' file locks the core frequency of the Pi's VideoCore at 250MHz, the off-load value for the Pi Zero and Three models, and the default for all other models.

Docs

Hope this helps,
Dave.
by dgordon42
Wed Jun 07, 2017 7:16 pm
Forum: Automation, sensing and robotics
Topic: T6713 CO2 Sensor wiring help
Replies: 9
Views: 2822

Re: T6713 CO2 Sensor wiring help

If your T6713 shows up using the 'i2cdetect -y 1' command, then it's basically working, and the wiring and voltages level are probably OK. What address does 'i2cdetect' show your device to be at? Are you aware of the difference and usage of 7 or 8 bit addressing on the I2c Bus? I have never used a T...
by dgordon42
Wed Jun 07, 2017 1:37 pm
Forum: Automation, sensing and robotics
Topic: T6713 CO2 Sensor wiring help
Replies: 9
Views: 2822

Re: T6713 CO2 Sensor wiring help

Does the T6713 device show up if you run the

Code: Select all

i2cdetect -y 1
command?
vishnu92narayanan wrote:I am using 3.3v supply.
The T6713 is a 5V device, but read the posts above carefully before connecting a 5V device directly to the Pi's I2c Bus.

T6713 Datasheet
T67XX Users Manual

Hope this helps,
Dave.
by dgordon42
Tue Jun 06, 2017 12:45 pm
Forum: Beginners
Topic: Controlling the shutter speed of Pi cam
Replies: 3
Views: 773

Re: Controlling the shutter speed of Pi cam

Ginnychabada wrote:1.What is the units in which this function takes in input. (seconds or milliseconds)?
I have never used the Raspicam C++ library, but the 'raspistill' command sets the shutter speed in MicroSeconds.

Code: Select all

raspistill --help
Hope this helps,
Dave.
by dgordon42
Tue Jun 06, 2017 11:54 am
Forum: General discussion
Topic: What is my correct locale?
Replies: 9
Views: 2727

Re: What is my correct locale?

Excellent. So rather than use the NOOBS->Debian->Menu->Preferences->Raspberry Pi Configuration ->Localisation->Set Locale->Country route, which loses me after that, looking for Belize, which so far as I can see is not there, you say I should use from Menu->Accessories->Terminal 'sudo raspi-config' ...
by dgordon42
Sat May 27, 2017 5:15 pm
Forum: Troubleshooting
Topic: Pi 3B UART limited to 9 chars?
Replies: 17
Views: 3464

Re: Pi 3B UART limited to 9 chars?

I don't know why your Serial Port is only sending 9 bytes over that loopback test, it's not something I've seen before. You could try editing the line: serialPort = serial.Serial(port, 115200, timeout = 2) and reducing the baud rate to, say 9600. Sometimes, depending on the wiring used, the port won...
by dgordon42
Tue May 09, 2017 8:26 pm
Forum: Beginners
Topic: matplotlib and Python 3
Replies: 32
Views: 32568

Re: matplotlib and Python 3

And how did the text file test go?

Dave.
by dgordon42
Tue May 09, 2017 7:49 pm
Forum: Beginners
Topic: matplotlib and Python 3
Replies: 32
Views: 32568

Re: matplotlib and Python 3

Given that 'apt-cache' reports that both the Python2 and Python3 versions of 'matplotlib' are installed, yet 'find' cannot find any of it's files on your SD Card, I am starting to suspect your SD Card. Check your SD Card's free space with: df -h Check that you can write a new text file to your SD Ca...
by dgordon42
Tue May 09, 2017 7:30 pm
Forum: Beginners
Topic: matplotlib and Python 3
Replies: 32
Views: 32568

Re: matplotlib and Python 3

python-matplotlib: Installé : 1.4.2-3.1 Candidat : 1.4.2-3.1 Table de version : *** 1.4.2-3.1 0 500 http://mirrordirector.raspbian.org/raspbian/ jessie/main armhf Packages 100 /var/lib/dpkg/status python3-matplotlib: Installé : 1.4.2-3.1 Candidat : 1.4.2-3.1 Table de version : *** 1.4.2-3.1 0 500 h...
by dgordon42
Tue May 09, 2017 6:42 pm
Forum: Beginners
Topic: matplotlib and Python 3
Replies: 32
Views: 32568

Re: matplotlib and Python 3

Post the full output from

Code: Select all

apt-cache policy python-matplotlib
apt-cache policy python3-matplotlib
Dave.
by dgordon42
Tue May 09, 2017 2:52 pm
Forum: Beginners
Topic: matplotlib and Python 3
Replies: 32
Views: 32568

Re: matplotlib and Python 3

For Python3, I think you still have a file called "matplotlib" that Python3 is finding in it's path before it finds the real thing. Report the output of: sudo find / -name matplotlib* For Python2, what happens if you start an interactive Python terminal and enter: import matplotlib.pyplot as plt Dave.
by dgordon42
Tue May 09, 2017 10:07 am
Forum: Beginners
Topic: matplotlib and Python 3
Replies: 32
Views: 32568

Re: matplotlib and Python 3

First, make sure that you do not have a file called "matplotlib" in your working directory when you run your Python program. If you do, rename it. If you still have the same problem, post the results of these three commands: uname -a apt-cache policy python-matplotlib apt-cache policy python3-matplo...
by dgordon42
Thu May 04, 2017 5:58 pm
Forum: Troubleshooting
Topic: USB not working anymore - RPi 3
Replies: 4
Views: 986

Re: USB not working anymore - RPi 3

Have a read of this thread.

Hope this helps,
Dave.
by dgordon42
Mon May 01, 2017 12:59 pm
Forum: Troubleshooting
Topic: RPi 3 USB Ports stopped working
Replies: 2
Views: 1036

Re: RPi 3 USB Ports stopped working

Check that 5V is available on the USB ports on your Pi.
If it's not there, have a read of this post.

Good Luck,
Dave.
by dgordon42
Wed Apr 26, 2017 1:23 pm
Forum: Python
Topic: Is this ShutDown Code Safe
Replies: 9
Views: 1116

Re: Is this ShutDown Code Safe

Looks like 'poweroff' and 'shutdown' all run the same SystemD code. [email protected] ~ $ which shutdown /sbin/shutdown [email protected] ~ $ ls -lh /sbin/shutdown lrwxrwxrwx 1 root root 14 Jan 15 03:29 /sbin/shutdown -> /bin/systemctl [email protected] ~ $ which poweroff /sbin/poweroff fla...
by dgordon42
Sun Apr 23, 2017 7:10 pm
Forum: Advanced users
Topic: Advanced GUI for Python scripts
Replies: 5
Views: 1794

Re: Advanced GUI for Python scripts

If there is an easy way to get the Tkinter library working over PuTTY I would love to hear that too! Tkinter requires a GUI to display it's stuff, and PuTTY only allows a remote CLI connection. Real VNC is bundled with Raspbian Jessie theses days, and that will allow a remote GUI connection to & fr...
by dgordon42
Sat Apr 22, 2017 10:58 am
Forum: Python
Topic: python hangs on serial write()
Replies: 9
Views: 9310

Re: python hangs on serial write()

Try changing all instances of "/dev/ttyAMA0" to "/dev/serial0" in your code. That's 'serialZero', not 'serialOh'. By default on a Pi Zero W, '/dev/ttyAMA0' is reserved by the system to talk to the Bluetooth Controller. The 'serial0' alias is the new way to address the Serial Port, and should work on...
by dgordon42
Fri Apr 21, 2017 6:55 pm
Forum: Beginners
Topic: No device tree options in raspi-config
Replies: 2
Views: 1009

Re: No device tree options in raspi-config

You can disable WiFi and Bluetooth on a Pi 3 by adding the following two lines to your '/boot/config.txt' file: dtoverlay=pi3-disable-wifi dtoverlay=pi3-disable-bt and running the once off command: sudo systemctl disable hciuart and rebooting the Pi. Details of these, and a lot more Device Tree Over...
by dgordon42
Fri Apr 21, 2017 8:41 am
Forum: Troubleshooting
Topic: GPSD - NEO-6M - Jessie
Replies: 25
Views: 5064

Re: GPSD - NEO-6M - Jessie

After reading this I'm a little confused around the pins, I'm using the card on the left of this image: The cards in the picture you posted should work to indicate which pin is which on the Pi. The bottom of the card should point to the USB connectors on the Pi. This site should also help to explai...

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