Questions tagged [i2c]
I²C stands for Inter-Integrated circuit, and is a data transferation system that allows connections between computers or microcontrollers and low-level peripherals (e.g. sensors or EEPROMS). It is a multi-master, multi-slave, single-ended, serial computer bus.
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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 ...
user3190780
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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 ...
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MPU-6050 is not being detected by Raspberry Pi
I am trying to interface MPU-6050 with the Raspberry Pi,
Since it require I2C connections so I have connected using the following pins:
3.3V connect to VCC
SDA connect to SDA
SCL connect to SCL
...
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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.
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I2C devices not detected
I'm running raspbian on my pi and followed this tutorial to get the i2c going. i2cdetect -y 1 used to detect my i2c devices but doesn't anymore. The sensor is connected like this:
Could this be a ...
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i2c data understanding [closed]
let me first say that I'm somewhat of a noob when it comes to i2c and serial communication. I've been trying for 2 days now to grasp it, reading datasheets, youtube videos etc. And I'm having a hard ...
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How can I automatically update the hwclock with NTP when I have internet connection
I'm using an RPi with Raspbian which runs the NTP-daemon by default. I have connected an rtc-ds1307 external i2c hardware clock. I was following the instructions given here to set it up:
http://learn....
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Analog input to the PI
I have a bit of a specialized question for you. Recently I got my Pi up and running, and am amazed at what it can pull off. But I want more.
I want to be able to record the output from an ...
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Raspberry Pi/"Arduino" communication
I'm looking to use a raspberry pi to speak to multiple "arduino" ATMEGA328p ICs (through a logic-level converter). I figure I can do this reasonably well over the GPIO RX/TX and use qualifiers to let ...
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How to install smbus to virtualenv?
How to setup python-smbus in the virtual env? Pip does not find any appropriate package. Is there a way to make main python installation's libraries visible to virtual env?
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Raspberry Pi and BMP085 (I²C)
I tried to get the temperature and pressure with the BMP085 sensor and my Raspberry Pi (256MB) via I2C. I used this Adafruit tutorial: Using the BMP085 with Raspberry Pi, but this isn't working for me....
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HD44780 Character LCD C++ Library
I'm looking for a way to connect my Raspberry Pi Model B to my HD44780 LCD, I've tried the Rpi-hw C++ Library but to no avail. You can find the issue about it here. I've been looking ever since for a ...
user9038
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Meaning of cmd param in write_i2c_block_data
I am testing i2c communication between Pi and Arduino.
The doc says:
write_i2c_block_data(addr,cmd,vals) Block Write transaction. int addr,char cmd,long[] None
I have this test:
On Pi:
...
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I2C (via BCM2835 library) and a mysterious error
The main function I'm having a problem with is where I'm writing a value to external EEPROM. I clear the EEPROM, then write my value to it, waiting 100ms afterwards.
#define BAUD_RATE (int)100e3 // ...
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Connecting to an LCD via I2C
I'm trying to use a SainSmart 20x4 LCD connected via I2C.
I can manually drive pins 0 & 1 to high and low so I know they work.
I've commented the blacklist I2C-bcm2708 and blacklist SPI-bcm2708 ...
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What does UU mean for RasClock
I acquired a RasClock made by After Thought Software (http://afterthoughtsoftware.com/products/rasclock) . This is a real time clock using i2c. I wanted to play with its other features via i2c but ...
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i2cdetect doesn't catch ANY address. How can I tell if I2C working correctly?
I'm having difficulties interfacing the Raspberry Pi to basically any I2C sensor. I've gone through a lot of tutorials on how to get the I2C driver to work and my connections are correct. Still, ...
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Controlling 400 LEDs from a raspberry pi
I have a client who has several large bronze signboards, each with 100-150 little light bulbs on it, totaling approximately 400 bulbs. The bulbs are turned on and off on a schedule, currently by hand ...
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I2C cable length and type
I have made some tests with a temperature sensor tmp102 connected with 1m long cables and it works great. Now I am wondering if I can use a 10m long cable and if yes, what type of cable shall I use? I'...
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How to get pin addresses on a MCP23017
Recently I purchased a few MCP23017. I've been reading up on them and I've gotten a few lights to turn on and such. I am having a problem trying to understand how to figure out the register address ...
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MMA8452 I2C module
I am working on Raspberry Pi Model B.
I am trying to interface this device over the I2C Bus on the Rpi.
My hardware Connections are:
RPi Accelerometer
Vcc P1_1 ------------------...
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Detect version 1 or version 2 Pi
I'm writing a small application that could run on version one Pi ( mine ) or a version two ( co-workers ) that uses the I2C bus.
Since the I2C bus is different depending on the version, I was ...
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Converting two's complement hex values to binary using PHP
I'm reading x-axis accelerometer data from an IC via the I2C bus using I2C-Tools' ( specifically i2cget ) in Linux. Here is the code that is reading these values:
$OUT_X_L_A = shell_exec( 'i2cget -y ...
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How can I read and write data to a Character Device File in Linux with PHP? [closed]
I'm trying to read and write to modules on the I2C bus on a Raspberry Pi using PHP. I'm using fopen() and fskeek().
Below is the code I've been trying to use to read data coming in from the physical ...
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I2C: Raspberri pi as a Slave
I am trying to make two raspberry pi communicate through I2C protocol. I got little information that how I can code as a master in C using i2c-dev.h. So my question is how to make one of my raspberry ...
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Raspberry Pi on AVC-LAN / IEBus
I'm planning on using my Raspberry Pi in my car as an XBMC server. I'll be able to select songs/videos using the Android remote control app, but it occurred to me that it would be really neat if I ...
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Connecting the HMC6352 compass module to a Raspi using I2C
I am trying to connect a HMC6352 compass module to my Raspberry Pi.
According to the datasheet I need to send an "A" for a read command. However, I am somewhat new to I2C and do not know how to ...
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Variaty of sensors sitting on a single board for RPI
Is there a board that has a few different sensors sitting on top of it and able to talk to RPI via I2C/1-Wire?
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I²C frequency changeable?
Is the I²C frequency meanwhile changeable? I read a few articles a while ago, that the frequency is not changeable.
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Couldnt get any value from accelerometer
I am using accelerometer MMA766 to read values. Used the following commands
root@raspberrypi:/home/pi# i2cdetect -y 1
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- --...
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Xenomai RTDM Skins for I2C, SPI [closed]
In another post I read that Xenomai could be used for real-time tasks like control loops.
I'd need to implement a real-time task which also talks to I2C and SPI. In this mailing list message I read ...
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PREEMPT_RT and RPi Drivers
I'm planning to do some realtime control loop tasks with the RPi. In this post PREEMPT_RT and Xenomai were proposed. I'm thinking about trying PREEMPT_RT, as I'd like to keep it as simple as possible.
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i2c Group on Arch
I'm trying to get I2C to run on Arch Linux with Kernel 3.6.11+ #352 PREEMPT with Raspberry Firmware from Jan 9, 2013 updated via rpi-update.
So far I have got good results by just loading the i2c-dev ...
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Configuring to read RTC at boot time
I have added an RTC to the I2C bus of the Raspberry Pi. If I follow the steps mentioned here (I am using the DS1307 RTC IC), I can run hwclock and read the time.
root@raspberrypi:~# modprobe rtc-...
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I2C library for Mono/C#
Is there a library to use I2C bus on RPi for Mono/.NET?
I was trying to find anything, but there are only libraries to work with GPIO but not with I2C.
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What is the difference between i2c-dev and i2c-bcm2708
I have been trying to figure out how to use i2c on RaspberryPi, and the What is the difference between i2c-dev and i2c-bcm2708 mentioned here? I would assume the i2c-bcm2708 module is specific to the ...
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Is there an I2C Library
Is there a simple library to talk to I2C for C++? I have found some stuff for python and Java, but I wanted C++. I was hoping someone has ported the Arduino Wire library so I could use code I have ...
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sample speed i2c
If running standard release of debian on my Rpi. How fast can I sample the sensor readings through i2c and save values?
Why Im asking, I tried to read a DS18B20 and save it,s values (wrote the ...
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Current state of I2C in Kernel and Kernel version in general
I need to use kernel drivers for some I2C peripherals, so I need kernel I2C support. As already discussed in a previous question, the current 3.1.9 kernel doesn't provide support for the SoC's I2C ...
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How to use a DS18B20 temperature sensor in my Pi?
I have a few DS18B20 temperature sensors. These are normally used in Arduino projects, but I don't see why not to use them with a Pi. There is a software called DigiTemp that seems to drive the device ...
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How to make raspbian load the i2c-dev module on boot up
I have installed 2012-07-15-wheezy-raspbian, and the i2c-dev module and i2c_bcm2708
are there and work with i2c-tools.
How do I get the i2c-dev module etc. to load at bootup?
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How do I bit bang I²C master?
I've installed RPi.GPIO. It doesn't support I²C yet, but can I use it to bit bang I²C?
I would just need the Raspberry Pi to be the master.
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How can I use I2C to talk to sensors?
How can I talk to digital sensors over the I²C interface?
Hardware:
Which pins on the Raspberry Pi's GPIO can I use?
Software:
What I²C libraries are available?
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Is it possible to communicate with I²C devices via the GPIO? [duplicate]
Is it possible to communicate with I²C devices via the GPIOs?
Also, are there any existing drivers or libraries that make this possible from Python?
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