Logic Components - Canon QY8-1360-000 Service Manual

BJC-7100

4.2.2 Logic components

1) MPU (IC1)
The MPU accommodates a 32-bit CPU, 25-bit address bus, 2KB work RAM, and nine
peripheral IO ports (interrupt controller, DMAC, timers, IO ports, AD converter,
DRAM controller, chip select controller, monitor timer, clock & power manager).
Internal CPU
The 32-bit CPU has 16 32-bit general-purpose registers and operates in sync with a
20MHz external clock input.
Address bus
The 25-bit address bus port is connected to the printer controller.
Data bus
The 16-bit data bus port for external devices is connected to the 8Mbit control ROM
and printer controller.
Internal RAM
The MPU has 2KB of internal RAM with 32-bit access.
Interrupt controller
The MPU has 21 interrupt request factors and 5 external interrupt factors, each
triggering interrupt processing.
Direct memory access (DMA) controller
The MPU has a 4-channel DMA controller that supports a 64MB address space.
Timer (stepping motor controller/sense signal controller)/monitor timer
The timer has two realtime port timer channels and seven multifunction timer
channels, which are connected to the respective sensors and motor drivers.
The stepping motor controller outputs double 1-2 phase excitation drive signals for
the carriage motor and 2-phase excitation drive signals for the paper feed motor.
The monitor timer monitors the signals at the realtime port timer terminals.
IO ports
The IO ports input receive data, output send data, input and output send requests, input
and output transmission clock requests, and input and output the transmission clock.
AD converter
The following analog signals are detected via the internal AD converter.
AN0: Ink optimizer head temperature detection from the head temperature sensor in
the BJ cartridge.
AN1: Black head temperature detection from the head temperature sensor in the BJ
cartridge.
AN2: Photo head temperature detection from the head temperature sensor in the BJ
cartridge.
AN3: Color head temperature detection from the head temperature sensor in the BJ
cartridge.
AN4: VH voltage detection from the AC adaptor via the printer controller.
AN5: Head rank detection from the rank resistor in the BJ cartridge via the printer
controller.
AN6: Ink-out detection from the antenna on the carriage.
AN7: Printer temperature detection from the thermistor on the control board.
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Part 4: Technical Reference