Go to advanced search

by pfletch101
Mon Dec 17, 2018 2:26 am
Forum: Advanced users
Topic: Does SD Copy make a valid copy of changing data files on a working system
Replies: 0
Views: 22

Does SD Copy make a valid copy of changing data files on a working system

I have a Pi 3B on which I am running weewx to monitor a Davis Weather Station and some homebrew software to monitor temperatures at various locations in my house and to record the price of electricity as it varies through the 24 hour period (my utility publishes an API for this). Other software runn...
by pfletch101
Sun Dec 16, 2018 10:24 pm
Forum: Raspbian
Topic: How can I prevent root to expand at first boot?
Replies: 32
Views: 8477

Re: How can I prevent root to expand at first boot?

I suggest looking in cmdline.txt to see if there is anything relating to raspi-config and if you see anything, comment it out. Doing so may stop the filesystem from expanding on first boot. But why would you want to? The OP wanted to be able to partition a (larger) SD manually after first boot to r...
by pfletch101
Sat Dec 15, 2018 10:42 pm
Forum: Networking and servers
Topic: Chrome: Your connection is not private (ERR_CERT_AUTHORITY_INVALID )
Replies: 3
Views: 78

Re: Chrome: Your connection is not private (ERR_CERT_AUTHORITY_INVALID )

Another possibility, costing some time and effort but no cash, would be to obtain and install a Certificate from LetsEncrypt (https://letsencrypt.org).
by pfletch101
Mon Dec 10, 2018 4:21 pm
Forum: Troubleshooting
Topic: Connect to VNC server using hostname?
Replies: 2
Views: 73

Re: Connect to VNC server using hostname?

This has been an issue since about April The theory at the time is that it was due to bug introduced into the MS win10 spring update. After trying a load of things, I gave up and just went back to using ip addresses It can be a bit intermittent and sometimes works (but then fails again) Yes, at lea...
by pfletch101
Tue Dec 04, 2018 3:17 pm
Forum: Beginners
Topic: Just a little humble direction!
Replies: 12
Views: 323

Re: Just a little humble direction!

FWIW, Visual Studio has a reasonably good Python implementation, though it obviously doesn't support Pi hardware-dependent libraries. If you are used to Visual tools, it may help you get started with Python.
by pfletch101
Sat Dec 01, 2018 10:20 pm
Forum: Troubleshooting
Topic: In LXDE, saving Weather Preferences?
Replies: 19
Views: 479

Re: In LXDE, saving Weather Preferences?

I've read lots of cautions about running as root, but I've been doing it about 20 years and no serious problems yet. It's not for everyone. I run as an administrator under Windows too and I've gotten pretty good at going into regedit and deleting the line that's causing a virus to start up on boot....
by pfletch101
Fri Nov 30, 2018 1:52 pm
Forum: Python
Topic: Stopping a python script from php
Replies: 6
Views: 156

Re: Stopping a python script from php

Ir worked. But just from the terminal. Since OS.mknod("file") requires root permissions. Is there a way to make it work from a PHP pagar without giving apache permissions todo execute sudo? You need to give the apache user (or the relevant group) write privileges to the directory that you are creat...
by pfletch101
Thu Nov 29, 2018 2:38 pm
Forum: General discussion
Topic: Is it possible to respond to a thread without bumping it?
Replies: 18
Views: 685

Re: Is it possible to respond to a thread without bumping it?

That's why such old threads should be locked, and preferably have "[obsolete]" added to their subject. Subjecting new naive users to obsolete info, as if the info is still completely valid, is about the worst thing you can do. I'm pleading for the automatic locking of all threads older than say 18 ...
by pfletch101
Wed Nov 28, 2018 8:53 pm
Forum: General discussion
Topic: WE ARE CURRENTLY EXPERIENCING HIGH TRAFFIC. WE'LL BE BACK SHORTLY.
Replies: 19
Views: 1472

Re: WE ARE CURRENTLY EXPERIENCING HIGH TRAFFIC. WE'LL BE BACK SHORTLY.

As pcmanbob says, things are getting rapidly and progressively worse. If the Board is not under attack again, throwing more resources at it (assuming this will predictably help) should be fast-tracked. FWIW, it took me six attempts to post this message!
by pfletch101
Wed Nov 28, 2018 8:26 pm
Forum: Python
Topic: variable not defined
Replies: 14
Views: 443

Re: variable not defined

Python is more simple-minded in this regard - it reads the script from the top down and will only recognize as a function something that has already been defined. It's not a case of being simple-minded, functions are objects like any other. Their names are just that, names which can have their valu...
by pfletch101
Wed Nov 28, 2018 4:37 pm
Forum: Networking and servers
Topic: Raspberry Pi Email Server complete solution
Replies: 3
Views: 8696

Re: Raspberry Pi Email Server complete solution

Keep this in mind If you are setting up an Email server using your residential Internet connection: WARNING : It might just happen that the Email server you've just configured, doesn't work! There is, probably, nothing wrong with your setup. Just, Be aware that MOST of the ISP (Internet Service Pro...
by pfletch101
Wed Nov 28, 2018 4:21 pm
Forum: Python
Topic: variable not defined
Replies: 14
Views: 443

Re: variable not defined

Following your advice has caused all my def functions and global statements to be at the top of my program. Thanks That's where they should be! Other languages can (appear to) cope with functions or subroutines being defined 'after' they are used - actually, of course, they do more than one 'pass' ...
by pfletch101
Wed Nov 28, 2018 4:11 pm
Forum: Python
Topic: Stopping a python script from php
Replies: 6
Views: 156

Re: Stopping a python script from php

Hello. I have a led changing color in an infinite loop and i need to stop it from a php page. Is threre any way to do this? Probably the most straightforward way to do this would be to have the php code either write a short file to a known location or delete a similar pre-existing file, and have th...
by pfletch101
Wed Nov 28, 2018 3:37 pm
Forum: General discussion
Topic: Make diy UPS for PI3
Replies: 14
Views: 13974

Re: Make diy UPS for PI3

I made one from 2 Poundland Powerbanks and published it at https://www.instructables.com/id/3-UPS-for-Raspberry-Pi Been running it for a few weeks and it's been working fine with a Model B Mk 3 Peter Cute! Do you have any power using devices (anything other than mouse, keyboard, or monitor) plugged...
by pfletch101
Fri Nov 23, 2018 4:40 pm
Forum: Automation, sensing and robotics
Topic: Remote site monitoring
Replies: 1
Views: 540

Re: Remote site monitoring

There are lots of Temperature sensors which can easily be interfaced to a Pi. Your choice will mainly depend on whether you want the temperature in the PI's immediate location or at a (presumably short) distance from it. For the battery voltage, you will need an A-D converter chip with a full scale ...
by pfletch101
Fri Nov 23, 2018 3:27 pm
Forum: Beginners
Topic: Making a smart thermostat
Replies: 2
Views: 219

Re: Making a smart thermostat

I would start by identifying the thermostat system and Googling around to see if anyone has already identified and decoded its wireless communications. There is another thread on this board about a (at least) similar system which complicates the project you propose because its thermostat sends out a...
by pfletch101
Fri Nov 23, 2018 3:01 pm
Forum: General discussion
Topic: user-pass-combination on Raspberry - how to solve the issue
Replies: 1
Views: 145

Re: user-pass-combination on Raspberry - how to solve the issue

By far your easiest options are: 1) (If you don't need to preserve your friend's system data) Download the latest version of Raspbian, use Etcher to burn it to the old Pi's SD Card, and start with a new, clean, system. or 2) (If you do want to preserve the old setup) Buy a new SD card and proceed ot...
by pfletch101
Fri Nov 16, 2018 11:03 pm
Forum: Beginners
Topic: 100% offline school computer. Wireless permanently disabled.
Replies: 28
Views: 890

Re: 100% offline school computer. Wireless permanently disabled.

fruitoftheloom wrote:
Fri Nov 16, 2018 8:24 pm
Take note the OP is working in a Educational Establishment which means a duty of care towards Students so any implementation has to be fool proof.
Worse - it needs to be smart kid proof! :)
by pfletch101
Fri Nov 16, 2018 3:36 pm
Forum: Troubleshooting
Topic: RPi3 b+ crashes each morning at 0530
Replies: 27
Views: 1209

Re: RPi3 b+ crashes each morning at 0530

All I can suggest is to remove attached HW until the problem goes away, to try and reduce the number of combinations that might be causing the issue. USB attached devices would be the first port of call. My only attachment to the Pi is power and the LED strand at two GPIO pins (one is data for the ...
by pfletch101
Thu Nov 15, 2018 7:28 pm
Forum: Other projects
Topic: Heater and cooler - peripherals to use?
Replies: 1
Views: 479

Re: Heater and cooler - peripherals to use?

Hi all! I'm trying to create a system to heat and cool a small 3D printed chamber. But...how? I've ordered a couple of mini fans and a peltier module, but the peltier module is not really controllable to my knowledge and far too hot for my needs. I was going to use the fan to blow air against the p...
by pfletch101
Wed Nov 14, 2018 11:32 pm
Forum: General discussion
Topic: Password of "pi" account is changed upon reset
Replies: 3
Views: 190

Re: Password of "pi" account is changed upon reset

LTolledo wrote:
Wed Nov 14, 2018 10:02 pm
It is always a good practice to immediately change the password during the initial setup .

10 to 16 character passwords are my preferred format.... others may prefer something else.
....and don't use the same password for different sites/purposes, even (perhaps especially) for other Pis
by pfletch101
Wed Nov 14, 2018 9:06 pm
Forum: General programming discussion
Topic: What OS and language to use for database project??
Replies: 15
Views: 1109

Re: What OS and language to use for database project??

The question of language, you will need to learn one at least. In the modern world everything takes on the structure of C, so that may be a good option. Though it is difficult to point to a true beginners tutorial on using C. The best one I know is the first 8 chapters of The C Programming Language...
by pfletch101
Tue Nov 13, 2018 10:04 pm
Forum: Beginners
Topic: Automatic Real Time File transfer to PC for Astronomy Project?
Replies: 5
Views: 194

Re: Automatic Real Time File transfer to PC for Astronomy Project?

I can think of a few reasons for a direct ethernet connection between the two systems in your observatory causing complications when you try to communicate with one of them from your indoors machine across a (different) WiFi connection. Probably the simplest way of making sure that everyone is on th...
by pfletch101
Tue Nov 13, 2018 3:53 pm
Forum: Beginners
Topic: Automatic Real Time File transfer to PC for Astronomy Project?
Replies: 5
Views: 194

Re: Automatic Real Time File transfer to PC for Astronomy Project?

I am not sure why you want to use something other than regular networking to transfer files between the two systems in your observatory. The fact that you are using networked apps to control them from your indoors computer shouldn't interfere with their talking to each other, unless they are on (eff...
by pfletch101
Tue Nov 13, 2018 3:35 pm
Forum: General programming discussion
Topic: What OS and language to use for database project??
Replies: 15
Views: 1109

Re: What to use??

If you are 'not a programmer' but want to use this project as a way into programming, I would use Python. Despite its quirks, it has a more gentle learning curve than most other common languages. If you don't plan to become at least something of a programmer, I am not sure how you plan to accomplish...

Go to advanced search