Raspberry Pi Forums

R61zt

I still prefer to use "dd" on any nearby Linux pc with plenty of hdd space. You take out the micro-sd from your raspberry pi, move it to a card reader on a Linux PC, do some stuff from a terminal (see "man dd") and wait for a long time without indication while it laboriously replicates an 'image' fi...

R61zt

Two unknowns which fit my screwups yesterday, do not fix your problem, but might give you some ideas to try: Changes in my config of apache2 (after restarting the daemon and apache2) were used by Firefox but not known to the default web browser yesterday. There might be some hardcoding (unknown) in ...

R61zt

I don't know the particular lap timer counter unit which you have, but I suggest that making a new one from scratch using IR beams, or magnets, or any other contraption which you can devise, would be a suitable hobby project and once you have got GPIO pins working, the program to do timer counting a...

R61zt

I get nearly the same as ghp.
cpu on a 256 MB original 700MHz single core pi goes to 0.3% "python" for about a second while the i2c measurement readout is in progress and then stays on zero for the time.sleep(4.99) or comparable delay. memory use according to top shows steady 11.2MB "python".

R61zt

To save costs, the raspberry pi does not have a clock running (like the one on a PC motherboard near to the 3V coin battery). Buying a separate clock is an optional extra. IF you have an ethernet connection when you boot, it checks by Network Time Protocol ('NTP') what is your local time on the rest...

R61zt

Bwangster12
My opinion is based on old tests a few years ago.
With my 256MB old rPi, 4.9 to 5.1 Volts did work, and 5.3 did not.
It did my board no harm to try.

R61zt

Yes, if you place the sensors far enough apart, for example near two ends of a corridor.
You can sketch a plan of your work area and on it sketch the wide fans of sensitivity of each sensor.

R61zt

I've not tried the method of klricks. The following worked for me : remove the sd card and put it into the other raspberry pi which has keyboard, mouse, hdmi, (ethernet) boot that other raspberry pi after login as "pi" passwd to set a password raspi-config from that text menu, that lets you "enable"...

R61zt

One PIR sensor will tell you only "present" or "not". Never mind that they might have more than one sense segment :- the built-in electronics is too small to poke or change in any way and your best bet is to buy more than one PIR sensor. The other way to do it, if you want millions of pixels, is wit...

R61zt

Updates creep seems to be removing known-good video codec formats and requiring newer ones which won't work without more than 20x as much memory as before and are not always available to download. For example, look up "youtube John West Salmon Bear" and see if you can find the bears fishing and kung...

R61zt

Try searching for "how do I make my raspberry pi into a high volume spam server" and see what you get ...
Alternatively, some internet searching for "warez" might do.

R61zt

Having posted the performance of my abnormal 256MB pi B, I think that I should post what a 'nice' newer one did. On an ordinary quad-core B2 with 1024 MB memory, running its desktop, opening a terminal /opt/vc/bin/vcgencmd measure_temp temp=35.8'C I've not tested this years' B3 but those have a high...

R61zt

Thanks. That measured T is 'normal' for electonics. My duff one is getting 68C now that I've slowed down the clock a little and got it working. Having eliminated 'same problem as me', I don't know what goes wrong with yours after a minute.

R61zt

If it is just "beeps" and "dings" which you'll want, then try reading up on GPIO outputs. As a typical tiny loadspeaker in pound shop headphones is 30 ish Ohms, which is much too low to directly drive from a GPIO pin, one resistor and one npn transistor is sufficient to go from a GPIO output pin to ...

R61zt

I'd skip the Win10 IoT thing entirely, buy a pinboard on 0.1 inch pitch and comparable bits and pieces to get from a few pins of the 40-way GPIO connector, a few resistors, a ten-pack of LED because those are nice for testing, a handful of bog standard npn transistors sufficient to switch the model ...

R61zt

If you think that this forum is getting bad late homework panics, there is another hobby computer forum where kiddies ask "how do I build a robot?" and "how do I make a death ray?". Recommendation is that such people write (compile if it is in 'C') and chmod 700 a program to repeat a very large numb...

R61zt

Passwords are placed somewhere so safe that you won't find it, and even if you did, would take thousands of days to decrypt. Your best bet on a low value home computer is to remove the sd card and manually copy any user files of value. On another linux computer those should show up from /media/<NAME...

R61zt

Taking care to not wear static-making fleece, and to touch the nearest grounded metal object such as a hot water pipe before doing this, how hot is the main dark square (the main chip) on top of your pi? My usual ones get warm and I had a faulty one which got too hot to touch and dropped ssh connect...

R61zt

I'm unsure about the default. Plugging the sd card into a raspberry pi which does have keyboard, mouse and hdmi attached, I typed sudo raspi-config and from the text menu selected enable ssh. While I was there, I gave it a more specific networkname than "raspberrypi". Powering off and moving the sd ...

R61zt

I'd suggest that PoE would be a nuisance to debug in a hobby setup so contrary to the rPi aims. In one morning I could solder on all 50 boards a red wire and a black wire for your 4.9 to 5.0 Volts supply. It is not hard and you can have any wishlist 2b you like. Mine won't boot from the 5.1V of an A...

R61zt

Much has been said about how far away 4 light years is. Rather than doing extra work to get a probe there within our lifetimes and get a signal back a few years later, how about an entirely different approach. How about getting all of the engineering knowledge of mankind onto a sort of "generation c...

R61zt

This is unverified speculation: Do you have enough memory to do virtual machines ? I'm ok writing this from an old 512 MB pi, but I've been noticing that video and other tasks which used to work fine with 256MB now don't. Rather than virtualising (and using up precious memory) why not get a new sepa...

R61zt

This is from old testing on an rPi B in 2013, so please could someone with newer hardware do this test with an adjustable benchtop dc supply to either confirm or deny these old findings : My rPi B 256 MB and B 512 MB were both able to boot only if supplied with between 4.9 and 5.0 Volts. That is, yo...

R61zt

I'd recommend python for what you are doing.

R61zt

How about linking two rPi with camera units, using GND and one digital pin on the GPIO to carry trigger information from either an external trigger or from one to the other.

Search found 65 matches

Re: Creating backup image of microSD card

Re: problem with Apache2

Re: Scalextric Lap Timer & Race Control

Re: time.sleep and 75% CPU

Re: loose the yyyy-mm-dd and hh:mm:ss

Re: Power Supply Test RPi

Re: PIR Sensor and Direction

Re: How to set it up headlessly the first time???

Re: PIR Sensor and Direction

Re: Raspberry Pi laggy video

Re: how can I send emails from my raspberry pi without gmail

Re: SSH - Putty Error

Re: SSH - Putty Error

Re: multiple source audio question...

Re: info about lego trains controlled by Raspberry

Re: Try something simpler first ?

Re: Lost password

Re: SSH - Putty Error

Re: headless ssh connection refused

Re: Wishlist

Re: Breakthrough Starshot - Mission: Alpha Centauri in 20 ye

Re: suddenly can't access my rpi except for ssh

Re: Rpi B+ under voltage

Re: Easiest programming language for controlling gpio pins

Re: Camera trap