I²C stands for Inter-Integrated circuit, and is a data transferation system that allows connections between computers and low-level peripherals.

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Troubleshoot MCP23017 and LEDs

Anyone have any tips to help troubleshoot turning a simple LED on connected through the MCP23017? I've installed i2c-tools, and smbus. Nothing in my blacklist.conf Added i2c-dev to /etc/modules. ...
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33 views

Connecting Adafruit NFC breakout and serial console at the same time

I am electronics newbie but have some programming background. My current hobby project is to make a "thing" which does things based on which NFC badge is waved at it. The tutorial [1] I am following ...
2
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1answer
35 views

I2C device inside case + GPIO ribbon outside case

I have a model B in a nice prefab case with a slot through it to connect a 26-wire ribbon to the GPIO header. However, I'd like to leave a small I2C based device inside the case as well. I've ...
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1answer
18 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
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1answer
33 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 ...
0
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1answer
42 views

Pins I2C cannot be used as input

When using pin 3 and 5 as inputs, I get only 3.3v and I'm not able to use them as inputs. I use the same code and circuit on all the GPIO pins the circuit worked on every single pin except on this 2 ...
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0answers
14 views

How to do a repeated start with the Raspberry Pi to get the MMA8452Q accelerometer working?

I am trying to use an MMA8452Q accelerometer with the Raspberry pi B+. I have it hooked up to 5 GPIO pins on the Pi, J8 pins 1/3/5/7/9. After installing some i2c libraries, the Pi recognizes the ...
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61 views

I2C problem reading data - only sometimes

I'm using this device, that acts as an I2C slave device on the address 0x23, for communicating with an arduino from a RPi model B. This is an nrf24l01 attached to an AT48 that provides an I2C ...
0
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1answer
45 views

Filtering noise w/ pi as FM transmitter and sound source

I have an I2C FM transmitter for the pi; it has a 3.5mm stereo jack for input. Everything works great -- I attached a short dipole antennae and get clear reception for at least 25'. However, if I ...
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0answers
44 views

Daisy Chaining MCP23017 & Addressing

I'm looking to daisy chain multiple MCP23017 chips (upward of 10) to essentially give me more IO to play with from my Pi. I've started to work on the circuit diagram, but I'm really lost with all ...
0
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46 views

TSL2563 Raspberry Pi Kernel Module for I2C Light Sensor Device

On Raspberry Pi, I've built the tsl2563 module with the help of rpi-source ( https://github.com/notro/rpi-source/wiki ). I did a sudo modules_install and sudo depmod and then successfully modprobe the ...
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2answers
46 views

I2C receive handler, as seen on I2C for Arduino

When managing smbus/I2C devices using python with the RPi, is there a way to register a handler function so it is called when a byte is available for read, like in Arduino Wire.onReceive()? Otherwise, ...
0
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1answer
34 views

Check whether an I2C slave device is ready or not

I'm using an I2C device connected to an RPi. The device only handles receiving one byte (which is then transferred via radio to a similar device on the other end, that acknowledges the reception of ...
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0answers
16 views

i2c connection to mopi not working on one image

I'm trying to setup a mopi on my model B running raspbian. At the moment I can't talk to the mopi unit using the mopi and mopicli utilities and i2cdetect shows the following... $ i2cdetect -y 1 ...
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39 views

PWM to control brightness on i2c LED backpack?

I have something similar to this, it works, but it's too bright! I am aware that LED brightness can be controlled by pulse width modulation, but I don't know if I can safely do that with an LED ...
1
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1answer
78 views

Basic hand (touchless) gesture detection, solution needed

I need a good solution for basic gesture recognition (touchless), like swipe left, up, down, right, "tap" hardware/software for Raspberry Pi. I've seen http://www.hoverlabs.co/#hover which looks very ...
0
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2answers
84 views

Use interrupts in i2C between Ardiono and Raspberry Pi

I'm really new to Raspberry Pi and Arduino programming (+ I2C). Recently I start working on a project where I have to connect an Arduino and a Raspberry Pi to send and receive data from each other. ...
0
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1answer
56 views

I2C and ST 24C64 (5V Problem)

I`m planning to use the 24C64 EEPROM with my Rasberry Pi. According to the datasheet the EEPROM "Single Supply Voltage" is 4.5 to 5.5 V. (Datasheet: ...
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1answer
75 views

Sending i2c commands from arduino to pi

The RPi and arduino are connected by I2C and the arduino sends coordinates to the RPi through the wire library. However, the RPi only receives and prints out 0 when it should print out the coordinate. ...
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1answer
192 views

Model B+ i2c issues with 7 segment display

I purchased a 4 digit 7 segment display from adafruit and got it working on my old model A running adafruit occidentalis operating system. I recently bought a model B+ and installed the latest version ...
0
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0answers
18 views

Which power measuring device can transfer the absolute value to a Raspberry PI?

Which power measuring device can transfer the absolute value to a Raspberry PI? Most power measuring device provide an LED which flashes 1000 times per kWh, but do not send the complete value. Are ...
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0answers
51 views

Is it possible to use GPIO's simultaneously?

I'm interested in using raspberry to control a number of brushless motors. PWM should be executed parallely to work in needed rate. As far as I've heard, RPi provides only consequent requests to ...
0
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0answers
77 views

Why is my RTC DS1307 not being recognized?

I'm trying to wire up a DS1307 RTC to my Model B Pi. I'm following the diagram as shown in this crude image and I've also tried it like this but it isn't recognized by the Pi. When I run i2cdetect ...
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2answers
430 views

Connecting two cameras into a PI

Is it possible? One connects to the CSI port and the other one to the GPIO ports and use the i2c interface to extract the data.
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1answer
86 views

Quadrocopter Motor Movement

A friend and I are trying to build a raspberry pi-powered quadrocopter. We've ordered four ESCs, four motors, and the Pi, but we're having trouble getting a motor to actually move. The motor makes a ...
0
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2answers
274 views

raspbian wheezy: Package 'i2c-tools' has no installation candidate

I just tried sudo apt-get install i2c-tools and got the following output: Reading package lists... Done Building dependency tree Reading state information... Done Package i2c-tools is not ...
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87 views

Should I remove fake-hwclock because my i2c RTC isn't always plugged in?

I have a i2c RTC (rtc-pcf8563) that runs great, but I don't always have it plugged in; is there a way to test to see if the RTC is plugged in and, if not, start fake-hwclock or will I have to dpkg ...
0
votes
1answer
131 views

Choosing an OLED / LCD Dispaly

I'm building a simple device where my Raspberry Pi talks to Google Calendar, and displays information about where I'm at on my office door. My code is all in Python It was simple until I started ...
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0answers
34 views

Checking if i2C connection has dropped

Have a RPi connected to an arduino via i2C. Every once in a while I lose my i2c bus connection.Does anyone know of a way to automatically checked for a dropped bus via software? I might configure ...
0
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1answer
76 views

Kernel module doesn't call probe function

I'm writing a kernel modul which should work on i2c. The problem is: the probe function doesn't load automatically. AFAIK, it should be called with a correct device driver name. Please correct me if ...
0
votes
1answer
149 views

i2cdetect-ed address shifting with each detect

I'm trying to use use an Adafruits 0.56" 7-Segment Backpack (with Holtek HT16K33 chip). My RasPi Rev2 is running Raspbmc. What's causing me problems is that the address of the chip (single one on the ...
0
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1answer
145 views

display LED Blink Count on I2C 16x2 LCD

I want to blink a LED and display its count on I2C 16x2 LCD. But LED is not glowing at all. I used https://www.adafruit.com/product/1115 which uses i2c . I connected LED with 270ohm resister between ...
0
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1answer
113 views

I2C LCD w/ buttons - C

I'm have a 16x2 LCD button shield for RPI similar to Adafruits. It works using the provided Python library so the setup is ok. The problem is I can't find any working C code or library to work with ...
0
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1answer
288 views

ImportError: No module named Adafruit_I2C

This looks like a common problem but it makes no sense to me I made a test program with "import Adafruit_I2C" as the only line and I get the Import error. I have run sudo apt-get update sudo ...
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1answer
121 views

Whats the most ideal way of communication between an Arduino and a Raspberry Pi?

I am kinda new to a raspberry Pi (just brought mine before writing this post) but i am looking to see what is the most ideal way for two way communication between an Arduino and a Raspberry Pi (USB, ...
0
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1answer
229 views

Pi4J i2c error: Error writing to /dev/i2c-1 at address 0x21. Got -20001

I'm trying to use the Pi4J java library to write data to an IO Expander via i2C. When I create a new instance of the MCP23017GpioProvider class using the following code: mcp = new ...
0
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1answer
118 views

i2c device doesn't work on different arch linux install

I have two Raspberry Pi's both model B revision 2, both running the most recent version of Arch Linux from NOOBS. I have tried my best to replicate the install procedure to get i2c working on both ...
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142 views

Making Raspberry pi talk to MyRio

I have a project where I need to use a NI MyRIO from NationalInstruments and a Raspberry Pi. I need to be able to send some data from some sensors on the RPi to MyRio and from MyRio to the RPi. The ...
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2answers
427 views

Raspberry pi GPIO extension

I recently started using rasperry pi. I am trying to do some home automation and controlling toy car motors. I am able to control the motors and 2 plug points. I wanted to control more servo motors. ...
0
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1answer
433 views

Tried the standard fixes - still getting FATAL: Module i2c-bcm2708 not found

I've removed the offending lines in (namely all lines)- /etc/modprobe.d/raspi-blacklist.conf I've adjusted /etc/modules to read: snd-bcm2835 i2c-dev i2c-bcm2708 When I try: modprobe i2c-dev I ...
0
votes
1answer
94 views

I2C stops working if a DiBcom DVB USB adapter is plugged

I can't help to get my I2C device (an Adafruit Pi Plate I just bought and built) to work in my Raspbian machine. Although the command sudo modprobe i2c-bcm2708 showed no errors, something strange ...
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0answers
89 views

is there a library for raspberry pi to use with MMA8452 I2C Three Axis Accelerometer Module?

I bought this accelerometer : http://www.fasttech.com/products/0/10000007/1012002-mma8452-i2c-three-axis-accelerometer-module I would like to use it with raspberry pi, I know that it is possible ...
2
votes
2answers
137 views

I2C with zener protection isn't working

I wanted to put some protection on my PI's pins and chose the zener voltage protection one, as described here. I used TZX3V3A zener diodes and 330 ohms resistors. Like this : Then i tried to ...
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3answers
903 views

How to use 2 x MCP23017?

I need to control 32 L.E.D's individually, now looking through the forum, the common solution is to use MCP23017 chips, as they can control 16 l.e.d's. With that in mind, I would require two chips. ...
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3answers
260 views

How to connect more than 1 am2315 temp rh sensor to respberrypi

Hi I have to read temp and rh from 2 locations. so I bought 2 am2315 sensors which is i2c logiced temp rh sensor. I connected it as shown in the below diagram, and its working fine. I can read data ...
0
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2answers
297 views

Disable i2c in Raspberry Pi

I want to disable the i2c in raspberry pi, so that I can use it as GPIOs. I commented the lines in the /etc/modprobe.d/raspi-blacklist.conf, but not working.
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1answer
2k views

Controlling Multiple analog RGB 12V led strips

I need to control several (5 to 10) analog RGB strips which have a separate power supply at 12V or 24V. Just like this one for example. I need to control the intensity of each colour channel for each ...
3
votes
1answer
107 views

Connecting Raspberry Pis With I2C

I would like to connect 6 slave RPis to 1 master RPi via I2C. Has this been done before and is it even possible. I know the I2C interface on the RPi has 1.8K pullup resistors so having all of those ...
3
votes
3answers
15k views

Safest way to connect Raspberry Pi to Arduino Uno R3

I am working on a robot using an Arduino Uno R3 and I wanted to have the ability of controlling the Arduino wirelessly, like stopping the Arduino without having to pull the power-plug every time. I ...
0
votes
1answer
365 views

Control a SainSmart 20x4 LCD?

I've got some SainSmart 20x4 LCD left over from my Arduino projects and I wanted to check if and how it's possible to get them running with an Raspberry Pi. I've come across this question. ...