I²C stands for Inter-Integrated circuit, and is a data transferation system that allows connections between computers and low-level peripherals.
3
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2answers
102 views
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 ...
1
vote
1answer
46 views
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? ...
0
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0answers
111 views
Using the wiringPi I2C Library
I am trying to figure out how this library works (https://projects.drogon.net/raspberry-pi/wiringpi/i2c-library/) . Firstly, what is int fd that all the functions require. It is never stated. I can't ...
0
votes
1answer
106 views
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 ...
2
votes
1answer
195 views
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 ...
0
votes
1answer
67 views
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 ...
0
votes
1answer
83 views
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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0answers
41 views
How can I read and write data to a Character Device File in Linux with PHP?
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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1answer
142 views
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 ...
1
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0answers
113 views
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 ...
0
votes
0answers
65 views
Parallax L3G4200D reading from Pi
I am looking for information on how to setup the Parallax 3 axis Gyroscope with temperature module. I cant seem to find good documentation anywhere on how to get it working. The only thing I can find ...
1
vote
1answer
180 views
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 ...
0
votes
1answer
149 views
Proven I2C sensors or expansion boards for RPI
Can someone point me to a good list of i2c sensors that will work with RPI - I am interested in pretty much any kind of them. Or perhaps there is an GPIO-mountable expansion board that I could use to ...
0
votes
1answer
74 views
I²C frequency changeable?
Is the I²C frequency meanwhile changeable? I read a few articles a while ago, that the frequency is not changeable.
2
votes
1answer
160 views
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: -- -- -- -- -- ...
3
votes
0answers
206 views
Xenomai RTDM Skins for I2C, SPI
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 ...
2
votes
1answer
262 views
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.
...
1
vote
2answers
311 views
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 ...
0
votes
0answers
178 views
Problems using ADS1115 with RPi
I am trying to figure out how to use the ADS1115 ADC with my RPi - using some example bash code for i2cset and i2cget I found in this forum, I'm getting inconsistent readings. There seems to be a ...
-1
votes
1answer
311 views
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 ...
1
vote
2answers
711 views
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.
0
votes
1answer
283 views
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 ...
1
vote
2answers
1k views
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 ...
1
vote
1answer
348 views
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 ...
7
votes
3answers
244 views
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 ...
8
votes
2answers
10k views
How to use a DS18B20 temperature sensor in my Pi?
I have a few DS18B20 temperature sensors. These are normally used in Arduino but I don't see why not to use them in a Pi. There is a software called DigiTemp that seems to drive the device and I have ...
6
votes
2answers
3k views
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?
7
votes
1answer
975 views
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.
15
votes
3answers
9k views
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?
7
votes
1answer
1k views
Is it possible to communicate with i2c devices via the GPIO?
Is it possible to communicate with i2c devices via the GPIO?
Also, are there any existing drivers or libraries that make this possible from Python?

