Microstrain Inertia Link setup with Duemilanove

hey guys i could really use your help for a senior project. i got it to move servos but my problem is that i have Microstrain Inertia Link but cannot get it to talk to the duemilanove which our team just bought. i tried the serial.read and other codes i found online and i cannot get anything from it. From an individual online, i found the following to start the proper format to which i could add too but i still get nothing. from the source code available from Microstrain, a coding involving 0xC2 for acceleration and angular rates will be necessary but i want to know first how to get anything from it. ANY HELP WOULD BE GREATLY APPRECIATED. Thanks

#include <NewSoftSerial.h>

NewSoftSerial imu(7, 5);

void setup()
{
imu.begin(9600);

Serial.begin(9600);
}

void loop()
{

if (imu.available())
{
Serial.print("IMU: ");
Serial.print(imu.read(), BYTE);
}

}

So how are you connecting this to the Arduino?

It has an RS232 output so you can't just connect it up to the Arduino lines, you need a level converter like the MAX232 chip.

Your code shows you are not sending it anything, do you expect it just to send serial data without giving it a nudge?

well i was hoping to initiate the communication to see if something happens. is this a chip necessary? so there is no way around this? we are trying to build a rocket and all programming is essentially complete but the communication with the Inertia Link is holding me up.

Thank you

I asked :-

So how are you connecting this to the Arduino?

You did not answer so it is a bit difficult to answer the following questions. Assuming that you are using the RS232 output of this device.

is this a chip necessary?

Yes or some other way of converting +12 to -12V signals into 0 to 5V signals and inverting them so that -12 gives +5V and +12V gives 0V. It can be done without this chip but you still need a fist full of transistors and diodes to do it.

so there is no way around this?

No.

Also if you have connected an RS232 signal directly into your Arduino you might have blown up an input pin.