For questions dealing with devices that measure the physical world around us and translate it into signals for the Raspberry Pi.

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3
votes
1answer
41 views

How to read Analog 5V sensor ouput with Digital 3.3V GPIO?

I bought the "Sunfounder Sensor Kit" for Raspberry Pi 2, but the whole content is made for Arduino (5V). I have bought ADC, Level Shifters but I am stuck because I think I certainly miss a simple ...
-3
votes
0answers
17 views

IR projector and IR-receiver for Raspberry Pi [on hold]

I would like to know if there are any IR-Projector and IR-Receiver for the raspberry. I'm thinking something similar to kinect sensors. And which VGA Cameras are there for the raspberry?
0
votes
1answer
33 views

How to use E18-D50NK on a Raspberry Pi?

I have one question . I want to try out a sensor called E18-D50NK, which is a infrared proximity sensor, for obstacle avoidance. More details and information about this sensor can be found here : ...
0
votes
1answer
48 views

BMP180 wrong reading

I connected my BMP180 on Raspberry Pi, temerature reading is correct, but pressure reading is incorect. It says Pressure=100448.00Pa, Sealevel Pressure=10450.00Pa while my local weather station says ...
0
votes
2answers
45 views

Is this possible to read internal CPU temp sensor directly from cpp code?

I am working on the kind of RPi platform to collect some external sensors data or control relays (using the remote tools like web or sms). Next problem I am tring to solve now is to get the direct ...
1
vote
1answer
132 views

LM35 temperature sensor not listed

I followed this guide: http://www.cl.cam.ac.uk/freshers/raspberrypi/tutorials/temperature/ to setup a LM35 temperature sensor on my Raspberry Pi. Changed the raspi.list file as well to deb ...
5
votes
3answers
673 views

Can I use the 3.3v pin instead of the 5v pin?

I am using a HC-SR04 ultrasonic sensors, and I don't have enough 5V pins on a Raspberry Pi, and I don't want to buy an expander. So is it possible to use the 3.3V pins on some of the sensors? What ...
0
votes
2answers
78 views

Is the Raspberry Pi suited for sensor and voice recognition project?

I am going to do a project in which the user moves his head in order to control the cursor across the computer screen using accelerometer sensor and gyroscope sensor (not combined). And for the mouse ...
1
vote
1answer
46 views

Measure the frequency of a 555 timer

I try to design a moisture sensor for the raspberry pi. To get a more stable measurement my idea was to use the 555 to generate a frequency depending on the capacitance. The circuit looks as follows: ...
0
votes
1answer
26 views

IOError exception not handled within signal handler

I am usig a RPi as a datalogger for an accelerometer, the ADXL345 breakout from Sparkfun. Since I need the accelerometer to sample at an exact frequency of 200Hz, I am using a signal to trigger the ...
0
votes
1answer
45 views

Vibration sensor / accelorometer capable of measuring vibrations caused by trains passing by

We live pretty close to the rail tracks, and for a long time I wanted to create a system that is capable of measuring the vibrations of the trains passing by. I tried to do it using the Sudden Motion ...
1
vote
1answer
24 views

Raspberry Pi Rapid Development Shield-Atlas Scientific-Reading Two(2) Sensors at the Same Time

Has anyone tried to use Atlas Scientific Raspberry Pi Rapid Development Shield: Can this shield run two(2) sensors at the same time(i.e., Thermometer probe and pH probe) and read both inputs? here ...
0
votes
0answers
9 views

GY-521_MPU6050 i am interfacing with LPC1768 the device is not recognized [duplicate]

I am not getting the raw values from gy-521_mpu6050 values .i connected scl,sda,ad0(gnd), vcc(5v),gnd. but i didn't connect the INT pin.i check the no_pull_up and operating frequency .if i want ...
0
votes
1answer
30 views

Powering via a motion sensor using a battery pack

I'm new to Raspberry Pi and I had a few questions. I want to connect a raspberry pi to a e-ink display, it will retrieve content over wifi. It will only display when a motion sensor picks up on light ...
1
vote
1answer
61 views

Raspi Type B with MQ sensors (updated)

Is there any other way to integrate raspberry pi with mq sensors?? I've been successful with one mcp3002 and one mq-2 sensor but is it possible to add another mq sensor (mq4,mq6) and should i provide ...
2
votes
5answers
112 views

How do I retrieve data from another Pi on the same network?

I would like to combine two tutorials (here and here) that I have found on sensing temperature with Raspberry Pis. I am already able to retrieve the temperature from the DS18B20 on multiple pis. ...
0
votes
0answers
53 views

Pi getting data from XinoRF

I'm trying to get the data from a DHT11 sensor connected to the XinoRF board. But it seems I get nothing from the wireless port ttyAMA0, but when I use the USB port ttyACM0, the python program seems ...
0
votes
1answer
135 views

Understanding the library from MCP3002 ADC chip

can somebody explain to me about this mcp3002 library used in analog to digital conversion?? It has some connection to my first question here. # botbook_mcp3002.py - read analog values from mcp3002 # ...
1
vote
1answer
409 views

Problems Regarding Raspberry Pi Project with MQ-2 Gas Sensor

Recently I have been learning Python implementations on Raspberry Pi's GPIO system. I'm interested in wireless sensor network examples and decided to make a fire alarm system using MQ-2 sensor as the ...
0
votes
2answers
76 views

Soil hygrometer without adc

I want to measure soil moisture using THIS sensor. I do not want to use ADC. In the sensor there is a digital output port and an analogue output port. I can use the digital output of the sensor ...
0
votes
1answer
44 views

dt11 is not detected on raspberry pi 2

I am trying to setup dt11 sensor using T-cobbler but its not getting detected. For reference attaching the screen shots. Any help really appreciated :) Thanks, sushanth
0
votes
2answers
179 views

Python taking pictures with raspberry pi camera

I have written this code to take a picture when it detects motion however when I run the code it prints 'picture taken' but does not save the picture. I know my camera works as I tested it in LX ...
1
vote
1answer
69 views

Wirelessly transmit sensors status

I am currently working on a home automation system and one of the challenges is big distances between my sensors and the the Raspberry Pi. For instance, I would like to monitor two rooms with PIR ...
0
votes
1answer
37 views

Detect stall current from motor and send gpio signal

I have a project which has a 12 V DC motor controlled by a raspberry pi through a l293d. The motor draws about 600-800mA from the power source while it is running, and > 1A (much greater) when it ...
0
votes
0answers
27 views

How to hook multiple SR04 Ultrasonics without soldering or using resistors / parts

What hat would be appropriate for attaching 3-5 Ultrasonic sensors like the SR04? For this question, assume I have to use a prebuilt 4-pin F-F dupont style connector.
2
votes
2answers
112 views

Resetting I2C? Or did I break my chip?

I'm connecting a TS45315 light sensor on an Adafruit breakoutboard to the I2C bus of my Raspberry. I access the data through the following simple Python script: ...
2
votes
1answer
206 views

Do I need a current limiting resistor in series with a magnetic door sensor?

I'm building an alarm system and I'm using a magnetic door sensor, conected to ground and a pin of the gpio set up with an internal pull-up resistor. As far as I know, this means that the pin will be ...
1
vote
1answer
87 views

433 Mhz transmitter on RPI always sending 00000000

I've bought a Realtek RTL2832 DBV for my RPI to read 433 mhz data and a transmitter HM-T433. I can successfully receive messages from two 433mhz remotes with the rtl_433 utility, but when I try to ...
2
votes
1answer
120 views

DS18b20 temperature sensor not found [duplicate]

Trying to install DS18b20 temperature sensor but it looks like the RPi cannot find it. From console: sudo modprobe w1-gpio sudo modprobe w1-therm cd /sys/bus/w1/devices/ ls But there is nothing ...
0
votes
0answers
34 views

Ultrasonic Sensor isn't consistent

I setup ultrasonic sensor on B+, following instructions given in this video. But each time I test I get a different distance for the same object which hasn't moved, seems like it decreases every time ...
2
votes
1answer
135 views

Accessing ADXL345

I'm trying to access an ADXL345 Accelerometer mounted on a Sparkfun breakoutboard via Python and I2C from a Raspberry B+. I'm following this tutorial However when trying to check for the sensor with ...
4
votes
2answers
208 views

Building a Raspberry Pi network monitor. My code is not working

Long story short. I moved, put my home server is a closet and started worrying about temp and humidity, saw a guide online to make a network temperature and humidity monitor from a rasberry pi and an ...
3
votes
1answer
92 views

Emulation of the Raspberry Pi with sensors

I am trying to emulate NOOBS or some other Raspberry Pi distro. I have tried QEMU but unfortunately this does not simulate peripheral devices (eg. Sensors) I was wondering if it was possible that a ...
1
vote
2answers
1k views

How to hook up an AM2302 temperature & humidity sensor several feet away from the Raspberry pi?

I have a raspberry pi running pipgio and am using the provided code under the python section to get the temperature and humidity reading from the AM2302 (http://www.adafruit.com/products/393). If I ...
0
votes
2answers
77 views

Ant and termite detection using PIR [closed]

I would like to detect ant and termite using either one of the following sensor. PIR or infrared object detection sensor. Is it possible to detect insects with them or it can detect only larger sized ...
2
votes
2answers
157 views

Soil moisture sensor compatibility

Can this sensor for ardunino can be used with raspberry pi b+ model? The specs of the sensor are Operating voltage: 3.3V~5V Dual output mode,analog output more accurate A fixed bolt ...
0
votes
1answer
73 views

external power supply to sensors

I will be using all of the following sensors at the same time on raspberry pi b+ model with 2Amp power supply. 1) DHT-11 Digital Temperature & Humidity Sensor for temperature and humidity ...
0
votes
0answers
209 views

Why my Raspberry Pi cannot find Si7021 (temperature and humidity sensor)?

I use this temperature and humidity sensor: Si7021, like below link http://www.dfrobot.com/wiki/index.php/SI7021_Temperature_and_humidity_sensor_SKU:TOY0054 I can get the sensor data by Arduino ...
3
votes
1answer
216 views

GPIO Temperature Sensor not Recognized

I recently tried to connect a temperature sensor (http://www.adafruit.com/product/381) to my RasPi via the GPIO, with a 4.7k (2Watt) resistor connecting the power and data (Source: ...
1
vote
0answers
110 views

BCM2835 Event Detection

I've got 2 motors, 2 encoders, a motor controller, and my B+ wired up. My B+ is running Arch with kernel: Linux drd 3.12.35-1-ARCH #1 PREEMPT Tue Dec 23 07:14:51 MST 2014 armv6l GNU/Linux. The 2 ...
1
vote
1answer
76 views

How to decide the amount of resistors for gpio

I will be using raspberry pi for connecting following sensors DHT-11 Digital Temperature & Humidity Sensor for temperature and humidity measurement HC-SR501 PYROELECTRIC INFRARED PIR MOTION ...
2
votes
1answer
714 views

Raspberry Pi as an captive portal with CoovaChilli

i'm looking to do something maybe not that common with my Rpi; I have a rowing machine and I want to connect it to my Pi to motivate me to do sport. To do this, I have an Arduino connected to a Pi ...
1
vote
0answers
119 views

pyvisa connection [closed]

I was hoping to use my RPi to read a sensor output, then (used as slave) to send the read values to a PC. I've been told that it could be done by using the pyVisa library in the master PC but I cannot ...
1
vote
1answer
78 views

Issues with multiple SDA sensors

I am facing some issues trying to connect two sensors which make use of the SDA GPIO. Ultra sound sensor HC-SR04 Gyroscope & Accelerometer MPU-6050 Separately, they work just fine, however ...
2
votes
1answer
72 views

Sensor minimum/maximum operating voltage

I've bought this sensor, and I'd like to connect it to Raspberry Pi (unless I manage i2c on dagu minidriver). The spec on the sensor say: Minimum operating voltage: 2.5 V Maximum operating ...
2
votes
1answer
447 views

How to connect a 12V fan sensor wire to the Pi

I have a 3-wire 12v DC fan (Sanyo Denki 9S1212M4011). It's actually getting 15V because my "12V" wall wart isn't accurate. When the fan is not running my multimeter tells me there is 14V on the ...
2
votes
3answers
125 views

Starting raspberry pi from button

I want to have a raspberry pi inside a hollowed out book with a contact switch that detects the book cover lifting, which will then send a signal to the pi to turn itself on/wake from a low power ...
0
votes
1answer
268 views

Maximum number of Sensors supported by raspberry pi [closed]

i would like to know how many sensors can be connected to raspberry pi at a time (i would like to connect sensors like temperature sensor,humidity sensor,pir motion sensor and 3 to 4 leds)
0
votes
1answer
30 views

Headers to connect xtrinsic sensor board

I have both (pi and board) as illustrated here. However, both boards have pins. Neither have the female ends for the connection. What kind of headers do i need? Are there female - female available? I ...
2
votes
2answers
2k views

Sensor to detect water/liquid level

I have a swamp cooler that does not turn off automatically when the water level evaporates below the safe level, and if I fail to turn it off even once I could damage it. The sensor simply needs to ...