Canon BJC 6000 - Color Inkjet Printer Service Manual

Buffer controllerWrites the received data into the DRAM's receive buffer automatically, controls theremaining receive buffer capacity, reads the print buffer automatically, and clearsthe data that has been read. The print buffer manages two separate areas for the 2heads.DRAM controllerPerforms control of the 16Mbit-DRAM's 16-bit data bus and 10-bit address bus,READ/WRITE control, RAS/CAS control, and REFRESH control, using the busdedicated to DRAM which is separate from the MPU bus inside the printercontroller.Stepping motor controllerTransfers to the driver IC the steady current drive waveforms needed to drivemotors. As the motor is sinuously driven, the data to be transferred to the IC is16-bit/step drive waveform serial data that consists of motor drive current, motortorque setting, phase information, etc.Interrupt controllerThe printer controller has 4 interrupt pins on it. The interrupt controller generatesparallel I/F, motor drive, and head drive interrupt requests to MPU(IC201). Also, itaccepts an interrupt signal from the reset IC.I/O portSends indicator lighting and the power supply voltage output control signals asoutput signals, receives sensor signals from the home position sensor, pumpsensor, and paper end sensor as input signals, controls the EEPROM data I/O,and sends the motor driver reset signal as output.b) MPU (IC201)Incorporates a 32-bit CPU, 6Kbit work RAM, 21-bit address bus port, 16-bit databus port, interrupt controller, A/D converter, and I/O port. The MPU selects thecontrol ROM, printer controller, or DRAM according to the chip select signal.Built-in CPU32-bit CPU operates in sync with the 20MHz external clock input.Address bus/Data busThe 21-bit address bus and 16-bit data bus operate in sync with the 20MHzexternal clock input.Interrupt controllerAllows the MPU to receive the power on/off interrupt signal, as well as interruptsignals from the printer controller.4-39BJC-6000Part 4: Technical Reference