HP LaserJet 9040/9050 Service Manual - Page 93

DC controller operations z The CPU (IC201) on the DC controller PCA controls the following printer operations: • Sequence of the printer • Communications with the formatter • High-voltage power supply circuit • Rotation of the pickup motor, lifter motor, pickup roller motor, and fan motor 6 • Communication with the duplexer and tray 1, if installed • Fuser heater control circuit and fuser heater safety circuit z The ASIC (IC202) on the DC controller PCA controls the following printer operations, according to instructions from the CPU: • laser/scanner • rotation of fuser/delivery motor and drum motor • sensors and switches • clutches and solenoids • rotation of fan motors 1 through 5 z The reset IC (IC203) monitors +3.3 V and resets the CPU and ASIC at power on. z The EEPROM (IC204) stores backup data. z The pickup motor driver IC (IC205) drives the pickup motor. z The pickup roller up-and-down motor driver IC (IC206) drives the pickup roller up-and-down motor. z The lifter motor driver IC (IC207) drives the lifter motor. z The fan motor control circuit turns fans on and off. Engine control system 77