Go to advanced search

by Aydan
Mon Aug 13, 2018 3:25 pm
Forum: Troubleshooting
Topic: [SOLVED] RPi 3 ttyS0 holds TXD high
Replies: 11
Views: 164

Re: RPi 3 ttyS0 holds TXD high

You can try switching the TX Pin to GPIO input mode.
by Aydan
Mon Aug 13, 2018 3:10 pm
Forum: Troubleshooting
Topic: [SOLVED] RPi 3 ttyS0 holds TXD high
Replies: 11
Views: 164

Re: RPi 3 ttyS0 holds TXD high

If you want to power off your slave unit, then you'll have to isolate the transmission lines.
Either via a dual supply buffer, an open collector buffer with pullup from the slave unit supply, an opto isolator, ...
There's many ways to do this.

Regards
Aydan
by Aydan
Thu Aug 09, 2018 2:51 pm
Forum: Troubleshooting
Topic: /dev/root full although all data is on /media/usb0
Replies: 3
Views: 87

Re: /dev/root full although all data is on /media/usb0

Here is what df -h says: /dev/root 30G 28G 971M 97% / devtmpfs 484M 0 484M 0% /dev tmpfs 489M 0 489M 0% /dev/shm tmpfs 489M 13M 476M 3% /run tmpfs 5,0M 4,0K 5,0M 1% /run/lock tmpfs 489M 0 489M 0% /sys/fs/cgroup /dev/mmcblk0p1 41M 22M 19M 54% /boot tmpfs 98M 0 98M 0% /run/user/1000 This would indica...
by Aydan
Wed Jul 04, 2018 1:30 pm
Forum: Camera board
Topic: Using framebuffer as overlay for the camera preview
Replies: 6
Views: 425

Re: Using framebuffer as overlay for the camera preview

@6by9, thanks for the tips. Now the problem will be to convince X11 to write the alpha value of an application widget to the framebuffer, and not showing me the desktop/app behind the window. :lol: This would not be a problem with colour keying. I may just have to run my ap in direct framebuffer mod...
by Aydan
Wed Jul 04, 2018 11:21 am
Forum: Camera board
Topic: Using framebuffer as overlay for the camera preview
Replies: 6
Views: 425

Re: Using framebuffer as overlay for the camera preview

The goal would be to use picamera in combination with a canvas widget inside a tkinter application to show the camera preview. I can kind of do this right now, with the drawback that the preview port will always be ontop of the framebuffer and I'd have to make it transparent or disable it completely...
by Aydan
Mon Jun 25, 2018 4:53 pm
Forum: Advanced users
Topic: Stop command in service not executed on shutdown and reboot
Replies: 1
Views: 112

Re: Stop command in service not executed on shutdown and reboot

You could try with Type=simple, systemd may ignore ExecStop for oneshot services.
On the other hand, why don't you start uptimerobot_status via the same unit file?

Regards
Aydan
by Aydan
Fri Jun 22, 2018 11:06 am
Forum: Camera board
Topic: Using framebuffer as overlay for the camera preview
Replies: 6
Views: 425

Using framebuffer as overlay for the camera preview

Hello Everybody, is there any way to put the camera preview layer behind the framebuffer and make the framebuffer partially transparent (e.g. by color keying)? What I want to do is to show the camera preview and have UI components (Buttons/Labels) ontop of it. I do not want or need to have those UI ...
by Aydan
Fri Jun 08, 2018 1:26 pm
Forum: General discussion
Topic: Antivirus for Raspberry Pi on a corporate network
Replies: 18
Views: 1027

Re: Antivirus for Raspberry Pi on a corporate network

A potential problem will be that you will probably need to get the source code, so you can compile it for the ARM CPU in the PI. There is an armhf package for clamAV in the debian repos: https://packages.debian.org/search?suite=stretch&arch=armhf&keywords=clamav So it should be in Raspbian as well....
by Aydan
Fri Apr 20, 2018 9:25 am
Forum: General discussion
Topic: Custom Operating System
Replies: 2
Views: 175

Re: Custom Operating System

Yes you can, have a look here
by Aydan
Tue Feb 13, 2018 8:04 am
Forum: Troubleshooting
Topic: ssd woes
Replies: 3
Views: 243

Re: ssd woes

Did you try booting with only the bootcode.bin on the sd card?
It could also be that the RPi ROM bootloader does not like your USB enclosure, do you have another one you could try?

Regards
Aydan
by Aydan
Fri Feb 02, 2018 9:56 am
Forum: Troubleshooting
Topic: Failed to load kernel modules
Replies: 1
Views: 160

Re: Failed to load kernel modules

Boot your Pi from another card and attach the "broken" card via an SD-card reader. Mount the root partition somewhere, e.g. /mnt/broken and mount the boot partition into /mnt/broken/boot now chroot into /mnt/broken and try "apt-get -f install" to repair the broken package, or "apt-get install --rein...
by Aydan
Mon Jan 29, 2018 10:54 am
Forum: Troubleshooting
Topic: After updating today, tons of kernel panics and errors
Replies: 11
Views: 706

Re: After updating today, tons of kernel panics and errors

did you change anything in /etc/apt/sources.list? For me it looks like the update installed incompatible packages for a different architecture. As for fixing, burn a fresh copy of Raspbian onto another SD-card and rescue any data from the old card with a USB card reader. I don't think you'll be able...
by Aydan
Mon Jan 29, 2018 10:48 am
Forum: General discussion
Topic: how to tell apart two identical USB microphones?
Replies: 4
Views: 482

Re: how to tell apart two identical USB microphones?

The 1.3.4.3 part of the device path between the semicolons should be fixed to the USB-hub-ports used for the device, so they should be deterministic for the specific hardware setup. You can also cross-check this with lsusb -t which will show all the hubs and their ports involved for the device. Rega...
by Aydan
Wed Jan 17, 2018 7:57 pm
Forum: General discussion
Topic: RIP SD card, you have had a long and fulfilled life
Replies: 0
Views: 212

RIP SD card, you have had a long and fulfilled life

Today I sadly have to announce the death of an SD card. After almost four years of daily service and 539GB worth of writes, it had a stoke and died. Jokes aside, I am surprised the card lived that long. It started acting up just before new years with system hangs, and today the system hung after onl...
by Aydan
Fri Nov 24, 2017 9:18 pm
Forum: General discussion
Topic: type text to 2 screens
Replies: 9
Views: 744

Re: type text to 2 screens

Sure, a GUI written with python's tkinter would lend itself for that. It's more or less "place text from textbox in html template and save to disk".

Regards
Aydan
by Aydan
Fri Nov 24, 2017 7:36 pm
Forum: General discussion
Topic: type text to 2 screens
Replies: 9
Views: 744

Re: type text to 2 screens

It's not as bad as it sounds. The really basic implementation would be to set up nginx webserver on your "server" computer, and have it serve a static website (a somple "index.html" file) containing the text you want to show directly. Then put <meta http-equiv='Refresh' content='60'> inside the <hea...
by Aydan
Fri Nov 24, 2017 8:13 am
Forum: Troubleshooting
Topic: External hard drive unmounts then remounts.
Replies: 9
Views: 601

Re: External hard drive unmounts then remounts.

SInce it's a 3.5" drive, it needs 12V and 5V to operate. Maybe the 5V regulator in the enclosure is marginal, and when transferring large amounts of data it drops the voltage. Another possibility would be that the enclosure doesn't have it's own 5V regulator and uses the 5V from the USB, which of co...
by Aydan
Tue Nov 21, 2017 2:41 pm
Forum: General discussion
Topic: type text to 2 screens
Replies: 9
Views: 744

Re: type text to 2 screens

I'd use a self-refreshing website on the "listeners" which is dynamically generated on the "server" (e.g. via PHP) and reads a text file (on the server) or from a database (mariaDB) where you save the content of the message.

Regards
Aydan
by Aydan
Fri Nov 10, 2017 2:16 pm
Forum: Troubleshooting
Topic: Udev rules don't run after reboot
Replies: 19
Views: 1668

Re: Udev rules don't run after reboot

I just got to thinking that if udevd is started while root is still in read only mode, then this would account for the rule not working on boot, but working on service restart. Normally udev rules should not need to write to files on "/" Would be interesting to know the startup sequence of Stretch. ...
by Aydan
Fri Nov 10, 2017 11:17 am
Forum: Troubleshooting
Topic: How to control a DC motor direction using single GPIO from raspberry pi.
Replies: 4
Views: 647

Re: How to control a DC motor direction using single GPIO from raspberry pi.

GPIO - HIGH - Motor forward direction GPIO-LOW-Motor Reverse Direction. This way the motor will always turn in one direction or another. I'm not sure this is what you want. What you could do with one pin is to use PWM: 0% full reverse 50% stop 100% full forward But then your motor controller hardwa...
by Aydan
Thu Nov 09, 2017 7:35 pm
Forum: Troubleshooting
Topic: Udev rules don't run after reboot
Replies: 19
Views: 1668

Re: Udev rules don't run after reboot

All were owned by the "grant" user. I have changed one as a test to "root" but still with no luck. What permissions would you suggest? Permissions should be 0644 and owner root:root meaning only writable by user root and user and group are both root. Is your udev rulesfile also only writable by roo...
by Aydan
Thu Nov 09, 2017 3:15 pm
Forum: Troubleshooting
Topic: Udev rules don't run after reboot
Replies: 19
Views: 1668

Re: Udev rules don't run after reboot

Who is the owner of "/home/grant/scripts/usbcheck.sh" and what are the permissions?
I suspect you cannot run scripts that do not belong to root and/or are user writable.

Regards
Aydan
by Aydan
Mon Sep 18, 2017 12:43 pm
Forum: General discussion
Topic: I don't understand this error message
Replies: 4
Views: 423

Re: I don't understand this error message

Check if you have mixed spaces with tabs in the indentation.
Python3 will complain about mixed indentation.
Python2 will see a tab character like a space character.

Regards
Aydan
by Aydan
Tue Aug 29, 2017 3:35 pm
Forum: Troubleshooting
Topic: raspi-config viewing issue "solved"
Replies: 6
Views: 507

Re: raspi-config viewing issue

Instead to get the screen in blue/grey of raspi-config with selector (red) i have a black and white screen without any selector. This might be due to your ssh session not supporting colours or the ssh server detecting wrong terminal capabilities. Check what terminal emulation (e.g. VT100) is set in...
by Aydan
Thu Aug 24, 2017 7:25 am
Forum: Beginners
Topic: 5.442001] random: nonblocking pool is initialized
Replies: 6
Views: 1290

Re: 5.442001] random: nonblocking pool is initialized

Hello Aydan Thanks for replying. So, from what you are saying I've put the monitor driver (The one on the CD that came with the display) in the wrong place. Is there any way to take the driver back out of the sd card so it boots to my tv screen (I'm using that as a monitor when not watching tv). Ju...

Go to advanced search