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by mahjongg
Fri Feb 23, 2018 11:32 am
Forum: Beginners
Topic: ,,
Replies: 5
Views: 187

Re: ,,

Banned OP for deleting his own posts (seemingly to delete evidence of doing something bad).
The thread is now meaningless, but I will NOT delete it.
by mahjongg
Fri Feb 23, 2018 12:53 am
Forum: General discussion
Topic: My Pi Is ANGRY!
Replies: 23
Views: 847

Re: My Pi Is ANGRY!

could we get back to the OP's original question, or is everybody simply so inclined to believe the OP blew up his PI that they don't care? :roll: p.s. i would be angry too, if I was blown up.... by the way, the common case is that somehow you have caused a "latchup" condition in your PI's main chip,...
by mahjongg
Fri Feb 23, 2018 12:45 am
Forum: Troubleshooting
Topic: Coin acceptor: read GPIO
Replies: 7
Views: 1901

Re: Coin acceptor: read GPIO

@ame What do you mean by the following phrases? I'm working on the same coin acceptor and I don't understand what you mean when you said the following: All you need is a pull-up to 3.3V Then a pullup from the GPIO to 3.3V What do you mean by pull up to 3.3v? read https://en.wikipedia.org/wiki/Pull-...
by mahjongg
Thu Feb 22, 2018 6:50 pm
Forum: Beginners
Topic: Measure the voltage output of a PV module
Replies: 43
Views: 1162

Re: Measure the voltage output of a PV module

Yes, I fear that without a complete understanding of the working, and limitations of this hack it will be impossible to get this working. Reading things like "I always get results like 8.6V" makes me thinking how would you know the result (which is a time) represents 8.6Volt, unless you have compile...
by mahjongg
Thu Feb 22, 2018 6:18 pm
Forum: Beginners
Topic: Measure the voltage output of a PV module
Replies: 43
Views: 1162

Re: Measure the voltage output of a PV module

Yes, but that is a completely different solution, and if you are introducing extra IC's, (you need three already for a low/middle/high detector) you will be better off using a real ADC, on the I2C port.
by mahjongg
Thu Feb 22, 2018 10:07 am
Forum: Beginners
Topic: Temperature log
Replies: 11
Views: 229

Re: Temperature log

added code tags, and deleted duplicate post.
by mahjongg
Wed Feb 21, 2018 11:39 pm
Forum: Troubleshooting
Topic: Can't print PDF with RasPi Printer share
Replies: 9
Views: 4400

Re: Can't print PDF with RasPi Printer share

none of the above posters has posted in the last four years..... :roll:

you may have more luck googling for it....
by mahjongg
Wed Feb 21, 2018 10:19 am
Forum: Beginners
Topic: Measure the voltage output of a PV module
Replies: 43
Views: 1162

Re: Measure the voltage output of a PV module

In my opinion a circuit like this has to be calibrated and tested before it can be put to use. During the calibration you will learn if it works as expected. Calibration should be something like putting various voltages between low and high on the input, and writing down how the software reacts, onl...
by mahjongg
Tue Feb 20, 2018 10:28 pm
Forum: Beginners
Topic: question about pi zero w
Replies: 4
Views: 292

Re: question about pi zero w

hi can you use a any dongle in the zero version 1.3 thanx Yes, and with an USB hub you can use multiple USB devices. if by "any" you mean any one at all, then no, you can only use dongles for which a driver exists (an ARM Linux driver). dongles that work on other raspberry PI's should work on the z...
by mahjongg
Tue Feb 20, 2018 10:55 am
Forum: General discussion
Topic: Could I use duck billed tweezers to fix my bent micro USB pins?
Replies: 6
Views: 650

Re: Could I use duck billed tweezers to fix my bent micro USB pins?

First (Adrian Bao's) post deleted at users request (thread cannot be deleted as I need everybody's approval).
by mahjongg
Mon Feb 19, 2018 6:35 pm
Forum: General discussion
Topic: Is my Pi Zero W faulty?
Replies: 4
Views: 178

Re: Is my Pi Zero W faulty?

Yes, you must make it so that pressing the button presents a different voltage (high or low) to the GPIO than when not pressing the button, you can do this in two ways; use a pulldown resistor to pull the resistor to a logical low voltage (lower than 0.8 Volt), and then use a button to put a high (h...
by mahjongg
Mon Feb 19, 2018 3:56 pm
Forum: Beginners
Topic: how do I uninstall programs?
Replies: 15
Views: 388

Re: how do I uninstall programs?

First, you should know that as Linux is very much case sensitive JMRI and jmri are two different things. also apt-get alone doesn't do anything, as it expect to be told what to do, and JMRI isn't something it can do. type "man apt-get", and read the result (man is the built in manual system of linux...
by mahjongg
Mon Feb 19, 2018 3:54 pm
Forum: Python
Topic: Infinite loop malfunction
Replies: 15
Views: 336

Re: Infinite loop malfunction

Due to contact bounce a pushbutton might not produce one event when pressed/released, it is easily possible it produced a very rapid stream of 15 "open/close events", that is normal, and must be resolved with either hardware, or software to remove the contact bounce.
by mahjongg
Mon Feb 19, 2018 3:42 pm
Forum: General discussion
Topic: Is my Pi Zero W faulty?
Replies: 4
Views: 178

Re: Is my Pi Zero W faulty?

No, it is not broke, and this is normal! why do you expect a wire that isn't connected to anything to carry "zero voltage"? in the unavoidable neighborhood of magnetic fields in your house this wont be true, as any wire acts like an antenna, and picks up electromagnetic radiation. Without an interna...
by mahjongg
Mon Feb 19, 2018 12:37 pm
Forum: General discussion
Topic: Replacing the Pi3 ethernet port?
Replies: 21
Views: 1449

Re: Replacing the Pi3 ethernet port?

The LAN9514 documentation https://www.google.nl/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwjV79GK_rHZAhXLfFAKHd7nAqEQFggzMAE&url=http%3A%2F%2Fww1.microchip.com%2Fdownloads%2Fen%2FDeviceDoc%2F00002306A.pdf&usg=AOvVaw1SZhhaIJKJ32-7ZoJWQ-N1 should provide you with more details about the magnet...
by mahjongg
Mon Feb 19, 2018 10:09 am
Forum: Troubleshooting
Topic: I fried my Raspberry Pi 3 B
Replies: 8
Views: 270

Re: I fried my Raspberry Pi 3 B

Yes, the setup of this circuit is such that the polyfuse should protect the over-voltage diode, but when it burns out it will most often simply short the power supply, unless the power supply is something like a car battery, the short-circuit D5 provides is enough to protect the rest of the PI. I wo...
by mahjongg
Mon Feb 19, 2018 10:02 am
Forum: Automation, sensing and robotics
Topic: Doorbell detection
Replies: 6
Views: 233

Re: Doorbell detection

@pcmanbob, yes that is exactly it, with the extra bonus of the 1K resistor, which adds extra security against programming errors.
Thanks for your help.
by mahjongg
Sun Feb 18, 2018 10:17 pm
Forum: Raspberry Pi Desktop for PC and Mac
Topic: cannot pair bluetooth mouse (debian x86)
Replies: 11
Views: 442

Re: cannot pair bluetooth mouse (debian x86)

All postings about x86 Debian will be moved here, no matter where they are found. simply to avoid confusion between Raspbian and x86 Debian. debian running on a PC with the raspberry PI desktop is NOT the same thing as Raspbian. And if the title is confusing, I will not hesitate to remove the confus...
by mahjongg
Sun Feb 18, 2018 10:09 pm
Forum: Automation, sensing and robotics
Topic: Doorbell detection
Replies: 6
Views: 233

Re: Doorbell detection

OOPS! no that circuit is even worse than your original. connect pin 4 (of the PC817) directly to GND connect pin 3 to GPIO 18 place the R2 4K7 resistor with one end connected to 3V3, and the other end to pin 3 (and thus also to GPIO 18) add a new 1N4148 diode, and connect it cathode to pin 1 (of the...
by mahjongg
Sun Feb 18, 2018 10:01 pm
Forum: Networking and servers
Topic: GPS module with serial interface to Raspberry Pi with an USB-Serial Port
Replies: 5
Views: 145

Re: GPS module with serial interface to Raspberry Pi with an USB-Serial Port

yes, that USB-serial adapter has a DB9 connector, and obviously uses RS232 levels, so it should work fine with an RS232 compatible GPS module.

note that some USB-serial adapter use a fake Chinese serial interface IC, that may nor work with all Linux built in drivers, but you can safely try it.
by mahjongg
Sun Feb 18, 2018 9:42 pm
Forum: Troubleshooting
Topic: I fried my Raspberry Pi 3 B
Replies: 8
Views: 270

Re: I fried my Raspberry Pi 3 B

if its any PI BUT a PI zero, it has an overprotection device that will attempts to protect the PI by shorting the 5V supply when you put more than 6V on it. This will normally burn out the PI's polyfuse, and if you are lucky the device survives this and the fuse will self-repair if you leave it alon...
by mahjongg
Sun Feb 18, 2018 2:18 pm
Forum: Raspbian
Topic: Raspbian::Stretch
Replies: 2
Views: 160

Re: Raspbian::Stretch

split off from older topic.
by mahjongg
Sun Feb 18, 2018 2:09 pm
Forum: Nederlands
Topic: een image schrijven op SD card voor raspberrypi 3b
Replies: 1
Views: 85

Re: een image schrijven op SD card voor raspberrypi 3b

7zip is een data compressie utility, en schrijft geen images weg, en win32diskimager is sterk verouderd. gebruik een moderne image writer zoals Etcher die pakt een gecomprimeerde .img file ook zelfstandig uit, geen 7zip nodig. een image zit ook niet in NOOBS, maar download je zelfstandig, (je bent h...
by mahjongg
Sun Feb 18, 2018 2:03 pm
Forum: Networking and servers
Topic: GPS module with serial interface to Raspberry Pi with an USB-Serial Port
Replies: 5
Views: 145

Re: Raspberry Pi to a Serial Port

does the USB-serial adapter you are using use RS232 levels, and/or does the GPS module use RS232 levels (that is + and - 10Volt levels), (It should as its using ad DB09 port) if not you should use serial levels that match, as RS232 levels and "TTL" levels do not mix and match. connecting RS232 level...
by mahjongg
Sun Feb 18, 2018 1:43 pm
Forum: General discussion
Topic: My Raspberry won’t boot
Replies: 2
Views: 123

Re: My Raspberry won’t boot

read the boot problem sticky: viewtopic.php?f=28&t=58151
Is my Raspberry 3 is dead ?
unlikely unless you have blown it up, and it gets very hot.

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