store the data in the appropriate location 306 fig7 illustrates an exemplary circuit diagram 700 for a digital information id unit the digital information identification id chip 320 should have the following characteristics 1 ability to transmit information serially from a sensor or valve to the dau via a single wire 2 ability to supply power and transmit data on the same wire 3 since id chips on the market require a pull up resistor 704 on the id pin 702 for identification additional logic should be included to determine if a sensor is connected or not 4 each sensor input should have a standard scheme of identification 5 sensor information should be stored locally in flash memory or eeprom 6 each sensor should have ample local storage space for identification configuration and calibration information 7 each sensor should have an identification code for the module model number revision level and serial number 8 interface should be read write capable 9 id pin 702 should be protected against reverse voltage over voltage and conducted rf noise 10 bandwidth for the digital interface should be kept low to assure solid communications over long cable lengths and reduced electromagnetic interference emi and 11 digital information id unit circuitry 700 should support at least three sensors using the same id.