Requirement of Pull-up resistors on SCL and SDA lines when unsed

Question: Is it required to connect pull-up and pull-down resistor on SCL and SDA lines when a device is not connected?

 

Answer:

Pull-up resistors are required on the SCL/SDA pins even if no device is connected. The resistors are required to allow EZ-USB logic to detect the "No EEPROM / Invalid EEPROM" condition.