You are unable to "read" unless there is a request sent.

Attempting to read i2c will pause forever (as you are experiencing) without knowing there is data. Do something like this...

1. Send a request for data

2. Read the known data size that has been requested

For more information, look at the i2c BlinkM example...

# Shift the bits over
# Set the LSB (first bit) to a 1
# When first bit is a 1 on i2c, that means
# it is a Read Address
$i2cAddress = 0x09

Print("BlinkM Address: " +  $i2cAddress)

# Tell BlinkM we want the RGB Values
i2cWrite(0, $i2cAddress, 0x67)

# Receive the RGB Values
$raw = i2cRead(0, AUTO, $i2cAddress , 3)

# Print the number of bytes
Print("Received: " + Length($Raw) + " Bytes")

# Print the hex value of each byte
PrintHex($Raw)

# Split the array of bytes and assign to each variable
$Red = GetByte($Raw[0])
$Green = GetByte($Raw[1])
$Blue = GetByte($Raw[2])

DJ,

Thanks for the quick reply.

Your script is setting the EZ-b as the master and the BlinkM as the slave. I need the EZ-b to be the slave.

The EZ-B is unable to be a slave - it's configured as a master by factory.

I am trying to use the EZ-b as a 'capability enhancer' for robots built with the Lego EV3. To do this the EV3 uses a Dexter Industries I2C sensor block. This block sets the EV3 as the I2C master.

I have connected the EV3 via an arduino and got it to work with the information in http://www.dexterindustries.com/howto/connecting-ev3-arduino/

Near the end is a section headed "EV3 as the Master".

BTW- https://synthiam.com/Community/Questions/6532 shows the robot that I wish to 'enhance' with all the super EZ-B capabilities. A video is at: https://www.youtube.com/watch?v=DiGyeV759JE

Again, thanks.

Hi @OldbotBuilder,

You could essentially run your robot with 2 masters. The ez-bv4 can communicate serially to the Arduino. You could write a program on the Arduino that could translate your serial data from the ez-b and create I2C commands to send to the EV3 controller, probably wouldn't be that efficient but it's an idea.

Otherwise, I would suggest to try interfacing the motors and sensors from the EV3 directly to the ez-b. I believe LEGO peripherals also communicate as I2C slaves, but I don't have enough info on these new LEGO kits to confirm that.

From what I read, it looks like the EV3 can only be a Master (no slave option) and the EZB as DJ said likewise is designed to only be a Master.

My thoughts are you would either need to use an Arduino in between the two. Or it might be possible to communicate with the LEGO EV3 over wifi using TCP/IP. This might work.

Jeremie and JustinRatliff,

Good ideas and I will look into both suggestions. Thanks to you both.

Now - how does the 'resolved by' credit get assigned?