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Building a wild thumper GPS enabled Raspberry pi Robot Serial vs I2C

Good morning,

I am trying to build a GPS guided wild thumper. I have invested in some hardware and have been mucking about with it for a while now. But to be clear, I am a beginner.

This is what I have:

-Raspberry Pi 2 with a NoIR camera

-T'rex Motor controller (Dagu)

-The 4WD Wild Thumper Chassis

-nRF24L01+ radio controller x2

-Arduino nano


-A Couple of SR04 Ultrasonic distance units

-A Battery 7.4 LiPo

Serial vs I2C communication

Hi, please, can you tell me difference between I2C and Serial communication and which is the best for communication Raspberry Pi 2 with Arduino (T'Rex Controller). Thanks

Banana Pi not detecting I2C

My hardware being used is a Banana Pi and Picaxe 28X2.

Controlling a Raspberry Pi / Arduino Bot from the Internet Part 2 of 3

This is part two of a three part Series to explain how I control my BotTwo semi-Autonomous Robot from a webpage on the Internet. 

Has anyone ported Bill Porters Easy Transfer for Raspberry PI?

I *REALLY* like Bill Porter's Easy Transfer library for Arduino.  Yes, I've Goo-oo-oo-gled this, but have not found any hits on Easy Transfer (Bill Porter's Easy Transfer, as opposed to that MickeySoft product)  for Raspberry PI.  


I would Love to be able to move a struct { }  from Arduino to Pi, just as easy...

HMC6352 Compass Module in Continuous Read Mode

I have a need (desire?) to use compass heading as part of my PID loop to keep my rover heading true.  Using my well established trial and error coding technique, I was unable to get a sufficient sample rate from the HMC6352 Compass module using code I pilfered.. er... borrowed (I plan to give it back!) from the Interwebs.

Looking for ideas on a I2C Pan/tilt stand-alone sonar

This quest to build a stand-alone I2C pan/tilt range finder controller started with an article here by Ladvien.  In    https://www.robotshop.com/letsmakerobots/node/39130, Ladvien explores using an ATtiny85 (84) as an I2C motor controller...

And in https://www.robotshop.com/letsmakerobots/node/39222,   Chris the Carpenter   gives us an awesome pan and tilt code example... so...

Identifying an eeprom chip

So a long while ago I was buying some parts and i saw a cheep 8 pin eeprom chip. I thought that i might use it eventually but didnt really understand them completely at the time. Now, the time has come where i think i might want to use this but i dont remember which specific ic i bought and thus i dont know the i2c adress that i would use to communicate with this.

It says on it:




Using PiFace but still using I2C

I got a PiFace Display in the mail not too long ago, and just cracked it open.
I got it as a tester to write a review, because I wanted the LED display and the infrared on it.

Short description This is cr3cX, a robot I am building for my son to play with, and with the hope to teach him some programming. Current version is cr3c4. Read more

Servo Controller: A thought experiment

First up, this is at best a work in progress, at worst only ramblings.

I have seen members asking about driving more than a handful of servos and getting the response that they can either use an arduino and its assorted libraries to drive 12+ servos, correction, up to 20 servos or get a dedicated controller board that seems to cost in the area of 50USD. I spent an hour or so knocking up an idea. I want to lay out my thoughts and see where it could or should go.


Video Encoding with CS4954


I have some new and interesting stuff to share. The attached photos demonstrate my progress with generating baseband video signals (CVBS or composite video) for wireless transmission (see my other blog posts). As I finally realised that video stream editing at 27MHz data rate (towards stereoscopic vision) is hardly possible with the Parallax Propeller, I turned over to hardware editing. In the first step I thought I should start with discrete logic IC's but a colleague of mine "persuaded" me to use an FPGA. Well, he was definitely right.

12 servos controller with Arduino
Building a robot with wheels or with legs needs a design completly different. One of the biggest difference is the type and number of motors. While for a robot … Read more
Yet another walking robot but starting from scratch.
Using a
Update August 16, 2011 The PCB boards arrived a day earlier than expected (ordered on a Friday, arrived the following Friday). Eleven brain boards and 66 leg … Read more

How to Connect 3 Arduinos using I2C?

I've tried hooking up 2 arduinos using I2C and I need to expand it to 3 now cause of the Razor IMU sensor, which is also an Arduino.


As the I2C uses analog pins 4 & 5, how do the master Arduino knows which slave it is talking to?

Intellibrain problems

Hello everybody. I'm trying to get my intellibrain bot to comunicate with arduino via I2C, but I get some errors which I don't know how to debug. Google doesn't help at all. Here is what I get on my display when I turn on the program:
"Code: 20&97b6 
8d57 8d24 839d"
and after it shows that very shortly it turns the program off. It happens both when arduino is on and when it's off.

Two I2C-slaves ==> i2cslave-command repeated?


In the near future I'll have to control 2 MD03 motor controllers via I2C. Now, I don't get much about the i2c-commands integrated in PicAxe µC's so I'd like to ask how I should talk to them. Should I issue the i2cslave-command everytime I want to speak to one, or should I issue it twice (euch with another address) in the beginning of the program, or is there another way that I don't now about?


Problems with I2C -- DISCARDED

I'm trying to control two motors  by means of a joystick. This means I've coupled the potentiometers inside the joystick to my Picaxe 28X1 and my Picaxe 28X1 to two MD03 motor controllers. 

While testing I'm using only one potentiometer and one MD03. The problem is that I cannot get the system to work.

The program I'm using right now is:

i2cslave %10110000, i2cfast,i2cbyte


readadc 0,b0

Make servo/whatever controller out of Picaxe 28x1 and control it from Arduino over I2C
While working on my first Arduino project I found out that servo library is not compatible with software serial library which is very bad for my project. So, I … Read more

Problem with I2C mode of 16f877a

I am having problem with I2C mode of 16f877a. I wrote a code for I2C ranging mode of the SRF02 sensors. At first I thought the problem was with the code, but then I debugged the circuit a little; the code is as below:

SRF02 and 16f877a in I2C mode ranging


I am trying to test SRF02 ultrasonic rangers I just bought and to do that I connected them as required, and wrote a program in MIKROC for I2C transmission. My problem is that everytime I power up the curcuit my PIC burns. I connected pull up resistors to each of SDA and SCL lines; could it be that these resistors impose too much current into SCL and SDA pins of the PIC? Maybe I have to use a buffer between bus and 5V? The code is below. I am new to embedded programming so any of your comments would be of much use to me.

Thank you,


The Code:

connecting an i2c device with an AXE020 project board.

I've been thinking about playing around with 

What should be the resistance between clock, and data on an I²C bus?

trying some i2c devices, though they aren't working, so i thought maybe they where shorting, my cheap multimiter reads 3kohm, is it suposed to be like this?

the device is a cheap ebay nunchuck, made myself a wiichuck adapter with vero board, though i'm measuring the resistance directly from the original socket, so it's not my homemade adaptor thats causing the probems...



i2c = PS/2?

Hi, can i connect i2c interface devices to my computer, by using the PS/2 jack?





Explore an environment, create maps, take pictures, never get stuck.
Using a
Tesla will be a multifunctional robot that will have priority tasks. Unlike other robots that will just "do" things, this robot will have tasks only if certain … Read more