Arduino + iRobot Create

Hello all,

This is my first post but I am an avid follower of this forum and the Arduino phenomenon in general!

What I am currently trying to do is use the Arduino (Diecimila) to drive my irobot create using the serial based Open Interface commands. I am using the hardware serial port (pins 0 & 1) on the arduino to communicate with the robot, and at this point am fully capable of sending commands to the robot.

The problem I am having is on the receive side of things - I am not actually able to receive anything from the robot. I have done some reading on this subject and it seems that the problem may be with the 1K resistor between the ftdi FT232 chip and pin 0. I have also read that it has something to do with the fact that the FT232 and the irobot can only source/sink 2mA (respectively); this leads to a voltage drop of 2 volts through the resistor and effectively no change in the state of the pin.

Is this problem fixable with external hardware or code, or do I actually need to switch the resistor between the FT232 and pin 0 to be something higher (~2.5K)?

Thanks for the help!



Any suggestions or help on this would be greatly appreciated :).