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by linderman
Sat Dec 12, 2015 11:22 pm
Forum: Troubleshooting
Topic: Problem with GPIO 4 after Adafruit DHT install
Replies: 4
Views: 893

Re: Problem with GPIO 4 after Adafruit DHT install

#dtparam=i2c_arm=on
#dtparam=i2s=on
#dtparam=spi=on
dtparam=audio=on
this is the exact output.
by linderman
Sat Dec 12, 2015 9:27 pm
Forum: Troubleshooting
Topic: Problem with GPIO 4 after Adafruit DHT install
Replies: 4
Views: 893

Re: Problem with GPIO 4 after Adafruit DHT install

Pin 4 is 5V. You probably mean GPIO 4 on pin 7. If so then something is using GPIO 4. The most likely candidate is the Adafruit DHT code. How did you run the Adafruit code? The next most likely is 1-wire code. Yes, i am using GPIO4 at pin 7. Usually i am running the Adafruit code: sudo ./AdafruitDH...
by linderman
Sat Dec 12, 2015 8:55 pm
Forum: Troubleshooting
Topic: Problem with GPIO 4 after Adafruit DHT install
Replies: 4
Views: 893

Problem with GPIO 4 after Adafruit DHT install

Hello guys/gals I did successfully installed Adafruit_Python_DHT from here: https://github.com/adafruit/Adafruit_Python_DHT sudo python setup.py install. The DH11 sensor works great - no problems with it. But then i disconnected it and connected a LED on same pin 4. Plugged in the RPi and it just st...
by linderman
Sat Dec 12, 2015 5:39 pm
Forum: Beginners
Topic: LEDs in parallel
Replies: 6
Views: 1270

Re: LEDs in parallel

Thank you for the good explanation!
by linderman
Fri Dec 11, 2015 8:05 pm
Forum: Beginners
Topic: LEDs in parallel
Replies: 6
Views: 1270

Re: LEDs in parallel

Ok , i tried parallel circuit with 2 leds using 1 resistor for both (330ohm) - nor LEDs or Pi got damage. Both LEDs produced visible light. But then i tried another thing , the result of which i dont understand: 2 Leds connected in serial circuit 3.3 pin -> resistor 330 ohm -> LED -> LED -> Ground I...
by linderman
Fri Dec 11, 2015 2:40 pm
Forum: Beginners
Topic: LEDs in parallel
Replies: 6
Views: 1270

Re: LEDs in parallel

Yes , but since the (330ohm) resistor is limiting the overall current to 4mA and single led can draw as much as 20mA , then both LEDs seems to be safe (even if one of the leds is using 100% of the amps left after the resistor). So isn`t this schema protecting both Pi and LEDS :?:
by linderman
Fri Dec 11, 2015 1:58 pm
Forum: Beginners
Topic: LEDs in parallel
Replies: 6
Views: 1270

LEDs in parallel

Hello, I want to connect 2 leds in parallel. Each of them have forward v. of 2V and current draw at 20mA. I want to use single resistor. https://www.raspberrypi.org/forums/download/file.php?mode=view&id=12487&sid=02ddeaf405beda3da9e686e672613acb So the calculation is: (3.3V - 2V)/0.04A = ~32ohms res...
by linderman
Thu Dec 10, 2015 4:43 pm
Forum: Beginners
Topic: Power state of RPi and connecting the GPIOs
Replies: 6
Views: 672

Re: Power state of RPi and connecting the GPIOs

Thank you for your help. "AB" device from above "is a must" for me
by linderman
Thu Dec 10, 2015 4:20 pm
Forum: Beginners
Topic: Power state of RPi and connecting the GPIOs
Replies: 6
Views: 672

Re: Power state of RPi and connecting the GPIOs

According to your replies i will always connect/disconnect pins when the RPi is down.

"Down" means also that the power adapter cable is unplugged right?
by linderman
Thu Dec 10, 2015 3:18 pm
Forum: Beginners
Topic: Power state of RPi and connecting the GPIOs
Replies: 6
Views: 672

Power state of RPi and connecting the GPIOs

Hello all, when it is safe to connect GPIOs? Only when RPi is totally disconnected from power source? RPi can show only red indicator? Or the ambitious one - GPIOs can be connected when RPi is fully running? I want to connect some LEDS and play, but i think it will be too show if after every change ...
by linderman
Wed Dec 09, 2015 8:18 pm
Forum: Beginners
Topic: Difference between GPIO and 3.3V pin
Replies: 4
Views: 2314

Re: Difference between GPIO and 3.3V pin

Thank you rpdom! Can i use pin 1 and any other i/o pins in the same time? Ex: I get 45 mA from pin 1. And lets say i want to get 8mA from 3 general i/o pins. This means that SUM output = 69mA? (Since i read somewhere, that max overall current from all GPIO pins must not exceed 50mA.) Thank you again
by linderman
Wed Dec 09, 2015 7:52 pm
Forum: Beginners
Topic: Difference between GPIO and 3.3V pin
Replies: 4
Views: 2314

Difference between GPIO and 3.3V pin

Hello all, sorry for the stupid question first of all. I know that GPIO pins can supply 3.3V and i must try to draw max of 16mA from a single pin. My question is about pin 1, 2, 4 (3.3V, 5V, 5V) - what i need them for? For example i can light a LED from any GPIO pin, why i need #1 - 3.3V pin since i...
by linderman
Fri Dec 04, 2015 11:43 am
Forum: General discussion
Topic: STICKY: Introduce yourself!
Replies: 3562
Views: 127404

Re: Introduce yourself!

Hey all,

My name is: Galin
Location: Bulgaria
Owner of: Raspberry PI1 B rev1
Work: Web developer/Programmer
by linderman
Fri Dec 04, 2015 11:41 am
Forum: Off topic discussion
Topic: What is your current PC/OS
Replies: 69
Views: 16540

Re: What is your current PC/OS

Lenovo B5400 - Windows 7 + Ubuntu 14.04

DesktopPC - Windows 7 + Centos 7

Raspberry Pi1 B rev1 - Raspbian

+

VPS1 - Centos 6.5
VPS2 - Centos 6.5

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