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?

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.

Hi,

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?

Thanks!

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

main:

readadc 0,b0

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:

Hi,

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,

Denis 

The Code:

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...

 

thanks 

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

thanks 

 

 

 

Right now I am working on my master-slave-slave board that will suit my needs for a long time. It has a master 4620, that communicates to another 4620 for processor assistance.

 4620 MASTER: Spaces for 5 servos, rs232, I2C, sn754410 motor controller, 8 ADC channels, 2x5 header so it is expandable into another board.

4620 SLAVE: Setting switches, proximity IR sensors (8 for complete sensing), speaker, encoders (rear and front for a car drive bot, left and right for 2 wheel operation), 38khz IR led driver, bumper switches and spaces for 6 servos I2C.

I hereby submit another plea to the robot gods out there:

I've read a lot of very informative info on both i2c and serial communication as a way for one IC to control others. My question is: which will work better for my needs?

My plan is to make a robot that has a seperate IC for each aspect of its behavior (movement, communication, etc.). So which is faster? cheaper? fewer wires? easier to program? I'm sure both have pros and cons.

Okay, go.

Hello! i have almost finished my analog inputs on my last project.. i have only one left and i need to attach some potentiometers to do some calibration.. I could really use some nice multiplexing. What i'd like is a chip with some analog inputs and possibly an i2c interface so that you can choose which analog pin to read and get a digital reading. Do you know if anything like this exists ?

So, i just wasted an evening trying to make an LCD with i2c work with my picaxe.

I connected the SCL and SDA of the board to the other end on the LCD. (of course not crossing them :P)  BTW on the picaxe the pins are: Digital input 3 = SCL; Digital input 4 = SDA, am i right ?

If so, other question is: do i need the two pullup resistors ? i've read somewhere that they're already there on the board. But if so, the pin should be high most of the time, shouldn't it ? testing with my voltmeter reads 0V. 

PS i have the picaxe 28x1.