Following is the simple IC code which can be used to test the sensor which is connected into the analog port 1 of the RCX brick:
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void main()
{
int sensor_reading; //variable for storing the current sensor reading
while(1) //infinite loop to obtain continious sensor readings
{
sensor_reading = light(1); //reading the sensor at analog port 1
printf("Port 1 = %d", sensor_reading); //display sensor value on the LCD
msleep(100L); //wait for 100 milliseconds for observing the value on LCD
} //end of infinite loop
} //end of main function
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